water heater safety valve leaking for sale

If you’ve been having issues with your water heater recently, you might find that you’re paying high energy bills, not getting access to hot water when you want it, or your water pressure is low.

Fortunately, by understanding how relief valves work, you can solve whatever problem you’re having with the one on your water heater. In this article, we’ll review everything you should know about this valve.

A water heater pressure relief valve, also referred to as a T&P valve, pressure relief valve, or water heater temperature valve is a safety feature that you can find on any water heater. The reason it’s there is to keep you safe in case the water pressure is too high.

Without this safety feature, your water heater could end up breaking. You could potentially end up with burns if the high water pressure is dangerously high.

This valve also ensures that there aren’t any leaks in your water heater, which would lead to low water pressure when you want to use it to wash the dishes or take a shower.

The water heater pressure relief valve is in place so that it can relieve excess pressure and temperature in a water heater if either of these is too high. Because this everyday appliance is a closed system, thermal expansion occurs in water heaters.

Here’s how it works. Whether your water heater is heated by electric elements or a gas burner, both the metal tank and the water inside expand when the hot water temperature is somewhere between 120 and 140 degrees.

It’s totally normal for the water and water heater to expand to a certain extend. After all, this is what naturally happens when the temperature rises.

However, when the temperature is 210 degrees—or the pressure is 150 pounds per inch (psi)—this is far too much pressure and heat in the water heater. If it’s the case, you should change your hot water heater temperature.

If your water heater pressure relief valve is working, this is when it will open. This releases steam and hot water from the discharge tube, making your water heater operate safely again.

On the micro-level, the functioning of this valve works like this. The relief valve itself has been set up by a professional or pre-designed to open when the temperature or pressure reaches a dangerous level.

When functioning properly, it will open as it’s designed to when the levels of heat or pressure are high. The liquid comes out through this auxiliary route, relieving the heat and pressure within the water tank.

This specific state that the water heater is in is called the “blowdown.” Usually, the “blowdown” is defined by professionals (and is used in the design or set up of the valve) as a specific pressure percentage.

The “blowdown” is usually somewhere between 2 and 20%. Once the pressure has reached the “blowdown” amount, the pressure relief valve will close again so that you can use the water heater as intended.

If you’ve been noticing any issues with your water heater pressure relief valve, then you need to know where it is on your water heater. Usually, you can find it on the top or side of this appliance. It’s a valve that’s connected to a plastic or metal discharge tube that points up.

The water heater pressure is already installed when you receive your water heater (or buy a home that has one already). It’s actually welded onto the tank; you’ll see a threaded inlet where it is.

This is for safety reasons. Everything has been done according to standards that have been mandated by plumbing codes. So if you’re having any issues with the valve, you’ll have to call a professional to have it fixed.

This said, if you’re only having issues with the discharge tube, this is easy to replace. You won’t have to drain or power down your water heater, and you can deal with it yourself.

This said, considering that there might be other issues causing discharge tube problems—issues connected to high water pressure or temperature—it’s safest to have a professional deal with this too.

If you suspect there’s a problem with your water heater pressure relief valve, you can do a test. This is actually good idea if you don’t have any problems at all, as this type of maintenance will protect your water heater—and yourself.

To get started, identify where the relief valve shut off is. Usually, you can find it upon the cold water feed, which is on top of the water tank, on the right side where the inlet is.

Finally, release the level so that it quickly snaps into the original position. If it doesn’t snap quickly into this original position, then your water heater valve isn’t working and needs to be replaced.

When your water heater pressure relief valve isn’t functioning properly, it’s usually for one of to two reasons. It either sticks so that it doesn’t properly open or close, or it has a leak, which means that it’s continually dripping, lowering your water pressure.

If your valve is sticky, then it becomes stuck in a closed (downward) or open (extended position). If it’s closed, then the valve won’t be able to relieve the heat or pressure that builds up in the closed water heater system. There could be a rupture as a result.

Sometimes, you can easily fix this problem by opening and closing the valve lever a few times. However, if it continues to stick, then you’ll need to replace it.

Your water heater is leaking? Make sure that it doesn’t come from the valve before replacing it. If your pressure relief valve is leaking, then this maybe because it isn’t seated properly in the tank’s threaded opening. This is quite a common issue if you’ve recently replaced your old valve with a new one. To fix this issue with this cause, you have to take several steps.

If the lever snaps into its original position and it’s still leaking, you need to turn off the gas valve by turning it to the off position. Then, shut the water off so you can replace the valve safely.

If a water pressure issue is what is causing the water heater pressure relief valve to not work, then it might be dangerous for you to change the valve yourself. Generally speaking, it’s a good idea to hire a professional to protect yourself.

Now that we’ve reviewed everything you should know about a water heater pressure relief valve you might have realized that you need to replace your water heater valve. However, to be as safe as possible, you want to hire a professional.

The water heater is known for its high heat and high pressure. The water heater temperature-pressure relief valve (TPR Valve), protects us from this high heat and pressure. So what is the TPR valve, why does it leak, and what should you do about it?

The TPR valve, also called, a pressure relief valve is a specialized valve at your water heater. This valve is typically on the top or side of your water heater.

The valve functions by releasing water if your water heater becomes too pressurized. Since heated water expands, the water heater can become a ticking time bomb if we were to continually build pressure in your water heater.

As seen in the featured image, a TPR valve is required to have a discharge pipe/tube. This tube should be aimed straight to the ground and never go up. This is because hot water will come out of the TPR valve as it releases water. Therefore, extremely hot water should discharge to the ground for safety.

Additionally, if a pipe were to go up, water will have to work against gravity to empty. So, it is possible a slow drip of the TPR valve will collect water in the tubing and ultimately rust out the valve rather than empty it to the floor.

Be one nominal size larger than the size of the relief valve outlet, where the relief valve discharge piping is installed with insert fittings. The outlet end of such tubing shall be fastened in place.

Typically, the solution to this is through a bladder tank, also named an expansion tank. The expansion tank works by allowing more room for the heated water to expand too. Depending on your location and home, an expansion tank might be required by code.

However, if you find the relief valve to continue to leak even after replacement, you should contact a plumber for assistance. A licensed plumber will be able to evaluate your system and decide on installing an expansion tank or other solutions.

Most homeowners are capable of doing a lot of their It"s technically not a pressure relief valve (or reducing). Those are installed on the mainline of the house. On a water heater, it"s called a T&P valve (temperature and pressure) or a pop-off valve.

The T&P valve serves an essential function as a safety feature. It offers your water heater built-in protection against high pressure and hot temperatures. It"s pretty standard for the pop-off valve to need replacement during the life of your water heater. The telltale sign that it needs replacement is when you see it dripping or leaking water. When you need a new valve, try one of the following options:

Drain a little water from the tank. It only needs to fall below the pop-off valve, wherever that resides. If you have a top mount configuration, you only need to drain a little bit. For side mounts, you probably need to drain about 10 gallons. You might take this opportunity to flush the water heater entirely, removing minerals and sediment in the tank. For a complete tutorial, read

Install the new T&P valve. Wrapping pipe thread tape around the threads of the valve, screw it into place. You should use a wrench, but you do not want to overtighten it.

Check for leaking. Fill the tank back up by opening the water supply valve back up. When the water level rises to the level of the new T&P valve, you can look for leaks.

Our best advice is don"t test the T&P valve. The reason is that the test requires you to flick the release lever. This action can cause an old valve to start leaking. Why rock the boat if it"s still working? Just give the T&P valve a thorough visual exam, looking for leaks, and call it good.

The beautiful thing about our tutorial guides here at PlumbersStock is that you can use our site to buy everything you need at discount prices. Check out all of our Bradford White. If you have any questions remaining about water heater pressure relief valve replacement, please contact us.

On the side or top of your water heater tank is a valve connected to a metal or plastic discharge tube pointing downward. The valve is called a T&P valve, or TPR valve, for "temperature and pressure relief."

If all goes well, a TPR valve never gets used intentionally except during testing. But in the event of an emergency or malfunction, this valve is of critical importance. It can potentially prevent your water heater from exploding. Understanding how a T&P valve works will help you keep your water heater in tip-top shape and prevent possible damage to your home.

A T&P valve is a valve with an attached tube located on the outside of a water heater. The valve provides relief to the water heater if the pressure exceeds normal operating limits, usually 150 psi.

Mandated by all plumbing codes, the T&P valve relieves excess temperature and pressure in a water heater if either reaches a critical point. A water heater is a closed system, and thermal expansion is an inescapable fact of both normal and abnormal water heater functioning.

In a standard water heater, the water is heated by a gas burner or electric elements. As the water reaches temperatures between 120 and 140 degrees Fahrenheit, both the water and the water heater"s metal tank expand.

Some expansion is normal, but too much expansion is unsafe. When the temperature reaches 210 degrees or the pressure reaches 150 psi (pounds per square inch), a properly functioning T&P valve opens and expels hot water and steam through the discharge tube.

When you purchase a water heater, the T&P valve generally comes pre-installed. A threaded inlet is welded onto the side of the tank. This inlet cannot be removed or replaced. The T&P valve is screwed clockwise onto that inlet.

Because the T&P valve is rarely used, mineral build-up can cause it to stiffen over time. This is a significant safety hazard because, in the event of a temperature or pressure spike, the T&P valve may not open as it should and the water heater might explode.

Water heater manufacturers recommend regular checking of the T&P valve. Wear closed-toe shoes to avoid scalding. Except for a bucket, no tools are required.

Before you begin, make sure you know where the shut-off valve of your tank is. It"s usually located on the cold water feed, on the right side inlet on top of the tank.

Release the lever and let it snap back to its original position. If the lever does not snap back into place, the valve is faulty and must be replaced.

In most cases, there are two problems you might have to address with the T&P valve: a valve that leaks by constantly dripping or a valve that sticks and doesn"t open and close properly.

When a T&P valve is leaking, it may be due to the valve not being properly seated in the threaded opening of the tank. This is especially likely if the leaking occurs immediately after an old valve is replaced. This can be remedied by shutting off the water heater and letting it cool down completely, then removing and rethreading the valve into the tank"s opening.

If the valve is leaking due to dirt or sediment trapped in the relief port, pull the metal spring lever back again and discharge water into the bucket. Once the lever snaps back again, if the water fails to stop completely, shut turn the gas valve to the off position and shut the water off to replace the valve.

A water heater that periodically discharges hot water and steam from the T&P valve may be set to a water temperature that is too high. Make sure that the water temperature setting is in the normal recommended range—about 120 degrees Fahrenheit—or no more than about 150 degrees Fahrenheit.

When stuck downward, the valve cannot provide relief if the system reaches maximum pressure. As a result, the water heater tank might rupture. When stuck in a fully extended position, the T&P valve will continually leak water down through the discharge tube, potentially flooding the home.

The stickiness of the valve can sometimes be remedied by simply opening and closing the lever several times. Jiggle the T&P valve by gently pulling the lever towards you. Much like jiggling a toilet handle, this action may be enough to unstick the valve. If this does not fix the problem, replace the valve.

However, some caution is necessary whenever working with a water heater, because the T&P valve can become damaged if the water heater has exceeded maximum pressure or temperature levels. If you suspect a pressure-related problem with your water heater tank, hire a licensed plumber to have the water heater inspected.

Water heaters come equipped with a temperature and pressure relief valve, also known as a TPRV. This valve allows water or steam to escape from the water heater if the temperature or pressure gets too high. This prevents a water heater from exploding or turning into a missile.

When a TPRV at a water heater leaks, it’s usually a simple fix; just replace the valve. These valves cost less than $15 and replacing the valve is a basic job. There are plenty of videos on YouTube showing how to do this, and the whole project probably won’t take more than fifteen minutes.

If you replace a TPRV and it starts leaking again, it probably means the valve is doing its job; it’s relieving excess pressure. When this happens, the fix gets a little bit more involved, and some troubleshooting is in order.

The TPRV on a water heater is set to discharge at 150 PSI or 210° Fahrenheit.  These numbers will be printed right on the valve, or on a tag attached to the valve.  See below.

If a pressure relief valve for a boiler is accidentally installed on a water heater, it will leak like crazy from the start. These valves may look identical, but they’re set to go off at 30 psi, not 150 psi.

The easiest way to do this is to get a gauge with a garden hose thread, connect it to an outside garden hose faucet, and open up the faucet. If that’s not an option, you can also use the hot or cold spigot for a washing machine. You should expect the pressure to be somewhere in the 40 – 80 PSI range with no other water running. If the pressure is over 80 PSI, it should be corrected. That’s too high for your system. The solution is to have a pressure regulator installed. Get a plumber to do that, as they’ll need to install an expansion tank at the same time. I’ll come back to those in a minute.

If the pressure is within the acceptable range, you probably have an intermittent problem with excessive pressure that can be easily re-created. Go run a bunch of hot water at your plumbing fixtures until you’ve exhausted the hot water supply on your water heater, and keep running the water for another few minutes. If you have several fixtures open, this should only take about ten to fifteen minutes. Now stop running water at all of your fixtures and wait.

You’ve just replaced the hot water in your water heater with cold water, which will cause your water heater to run for a while. This will cause the water to expand significantly until the water heater thermostat is satisfied. That might take about an hour or two. In most situations, this water will expand back out through the cold water inlet, all the way back to the water supply coming into the house. The municipal water supply for the house acts as a gigantic expansion tank… and nobody notices. This is illustrated in the diagram below.

A closed system exists when water can’t leave your house. One way for this to happen is to have a check valve installed on the water supply coming into the home. I don’t see a lot of these in Minnesota, but I do see them periodically.

The other way to create a closed system is to have a pressure regulator installed that contains a built-in check valve. With either of these installed, water can’t leave the house. When water expands and can’t go anywhere, pressure in the system increases. Watch your pressure gauge to verify this. Once the pressure gets to 150 PSI, the TPRV should do its job and leak.

When a closed system exists on the water distribution piping in a home, an expansion tank needs to be installed somewhere on the plumbing system. This is a simple and straightforward fix; an expansion tank will give the water somewhere to go when it expands, and the TPRV on the water heater will stop causing problems.

Expansion tanks are required when a closed system exists, both by water heater manufacturers and by plumbing codes. The Minnesota State Plumbing Code requires an expansion tank when a pressure regulator is installed (608.2):

An approved expansion tank shall be installed in the cold water distribution piping downstream of each such regulator to prevent excessive pressure from developing due to thermal expansion and to maintain the pressure setting of the regulator.

A water system provided with a check valve, backflow preventer, or other normally closed device that prevents dissipation of building pressure back into the water main shall be provided with an approved, listed, and adequately sized expansion tank or other approved device having a similar function to control thermal expansion.

A leak from your water heater’s pressure relief valve is a major concern, especially if it’s the first time dealing with this problem. While some people tend to panic and get help immediately, others may just shrug their shoulders and assume that the leak is a common occurrence. However, there are many causes of leaks in water pressure relief valves. And all these must be addressed immediately given the high risks of property damage and hazards that can occur if the issue is ignored.

The pressure relief valve gives steam and water a chance to escape when either the pressure or temperature in the water tank gets too high. A malfunctioning valve can cause the water heater to explode and is the major cause of water heater explosions. In water heater pressure relief valves, the valve is set to open when the pressure exceeds 150 psi.

A leaking valve is not always a broken valve. In some cases, a water heater’s pressure relief valve may leak because it is functioning as intended. As excess pressure is relieved out of your water heater system, some water may leak. This necessitates the need to test the pressure in your water heater.

The process is not complicated. However, if you are not comfortable checking the water pressure, you can always contact your technician. To test the pressure, use a pressure gauge and attach it to either the cold-water pipe or the hot water pipe. However, one of the easiest places to connect the pressure gauge is the outdoor hose faucets. For this, ensure you purchase a pressure gauge that is designed for garden hoses.

Turn off all water outlets and faucets. The pressure reading should be between 40 psi- 80 psi. If the gauge shows a psi reading of 150 and above, then the cause of the leak could be high pressure. If the water pressure is normal and the leak is persistent, then high water pressure is not the cause of the leak.

If you get a high-pressure reading, then you could be dealing with a closed plumbing system issue. This means that when the water is heated, the pressure increases as it should. But with nowhere to go, the valves open to relieve the pressure. Luckily, this can be solved by installing an expansion tank that gives the pressure an outlet other than a pressure relief valve.

Although rare, your water heater’s pressure relief valve could be leaking as a result of excessively high temperatures. However, the water has to be near the boiling point. To check the water temperature, ensure you turn on the hot water faucet. Run the water for one minute and use a meat thermometer to take the temperature reading. The temperature should be around 120 degrees. If more than this, then you need to have the water heater checked. The water temperature would need to be close to 212 degrees to set off the relief valve.

While this is an uncommon occurrence, it is not far-fetched. Your technician could have used a pressure valve for another appliance since they have the same function. However, these other pressure relief valves are set to go off at a lower psi. For instance, boiler pressure valves go off at 30 psi. If installed in a water heater, you are likely to get leaks immediately after installation. As such, if you have had your water heater for years and only experienced the leaks after a long period, then this is an unlikely cause of the leak.

A slight leak may occur if your water heater’s pressure relief valve has not been opened for a while, say a few years. While this leak is normal and may not be an indicator of a problem with the water heater system, you may need to replace the valve if the leak becomes more serious. It is cheaper to replace the entire valve than to repair it and have to deal with the same problem later on.

A leak in your water heater’s pressure relief valve could also be caused by a faulty pressure relief valve. While pressure relief valves barely break down, excessive wear and improper installation can cause extensive damage. Unfortunately, a faulty pressure valve can not be repaired and must be replaced. However, the cost of pressure valves is affordable and ranges around $30.

Know your water heater and how it functions– Water heaters can be intimidating, especially for people with less technical know-how.  Understand what every part of the system plays in heating water such as the water shutoff valve, drain valve, thermostat, and pressure relief valve. This eases the maintenance routine and ensures you have a fair understanding of any malfunctions.

Insulate the pipes and the water heater– By insulating both the cold water and hot water pipes, you get to prevent condensation while also reducing heat loss. Also, insulating the water heater helps to keep water hot when surrounded by cold air.

Carry out regular maintenance– Inspect your water heater monthly, ensuring that all valves and pipes are in good shape. This also helps you catch corrosion and leaks early enough before they turn out to be bigger problems. And every year, carry out a water heater flush. Given that you cannot pinpoint all problems, have a qualified technician inspect the system annually.

Regardless of the possible cause of a leak in your water heater’s pressure relief valve, please contact a qualified plumber as soon as possible. And if you think it’s a problem that you can solve without getting help, ensure you have a qualified plumber confirm that the system is performing optimally after. Water heater issues should not be taken lightly as they can cause more issues, even explosions.

If you notice that your hot water heater pressure relief valve is leaking, then it’s time to replace it. Most home improvement stores carry this replacement part and sell it at a reasonable price. In most cases, you can acquire a new water heater pressure relief valve for about $10 to $15. To fix your water heater pressure relief valve leak, follow the steps below.

You’ll now want to empty the water from the tank. You only need to drain the water a little below where the pressure valve is located. An easy way of doing this is to turn on the hot water in either your kitchen or your bathroom. The hot will then begin to drain.However, it’s also important to note that whenever you do any repairs to your hot water tank, as with the pressure valve replacement, it’s good idea to flush your tank and clean out the sediment at the bottom of the reservoir.

Now, release any air pressure that might still be lingering in your tank by raising the handle on the valve. By chance that your water heater has a metal pipe connected to it, you’ll want to remove it.

Equip yourself with a wrench and begin unscrewing the pressure relief valve. You’ll want to unscrew it counter-clockwise. Be extremely careful when you’re removing your faulty pressure relief valve.

If your hot water heater pressure relief valve is still leaking after the replacement, it could be because the valve is releasing some of the extra pressure that has built up within the tank. It’s important to remember that when cold water heats up, it begins to expand. As a result, the excess water will shoot back up the cold-water inlet if there’s not enough room in the reservoir.

The problem is, the water supply piping for your home will most likely have a check valve or a one-way valve imbedded to it. As the water expands and has no place to go, the pressure will continue to build and if left for a long enough period, your tank could explode causing damage to your property.

What’s the solution? Installing an expansion tank is your best answer. An expansion tank provides the water someplace to go when room runs out in the reservoir and should be installed near the water heater tank. In many cases, the expansion tank is installed above the water heater tank.

We explain where a pressure relief valve is usually installed on well water pressure tanks, how the valve works, and why pressure relief valves are an important safety feature on well tanks.

The water tank pressure relief valve shown in our photo (above) is marked indicating that it will open at water pressure equal to or greater than 75 psi. That pressure is pretty standard and you"ll see the 75 psi figure on valves used on water tanks and on some tankless water heaters too.

High pressure in a building water supply system can result if the water pressure switch that controls the well pump is damaged, or if the pump stays on too long.

Most submersible well water pumps can develop pressure exceeding the rated working limits of the water pressure tank or building water distribution system piping, fittings, and fixtures.

Excess water pressure can damage water system component as well as the pressure tank if not corrected immediately, and can also cause leaks within the piping system or at faucets and fixtures. Therefore on all building water supply systems using a private well and pump, a pressure-relief valve is recommended.

Water pressure relief valves are spring-controlled and open only in response to system pressure. That is, water temperature is not a controlling factor for these valves. For water service, these important safety devices are generally adjusted to relieve pressure higher than 75 psi. [1]

Watch out: water pressure tank fatality: we [Ed] are aware of a fatality that occurred in the Hudson Valley of New York State when a plumber, working alone on a water pressure tank and pump system was killed as the water pressure tank burst. - personal communication, Steve Vermilye to Editor ca 2001.

There was no pressure relief valve on the water system; a submersible well pump was installed; the well pump pressure control switch stuck in the "on" position.

When the pressure inside the water tank exceeded the tank"s design specifications the tank burst open. The plumber, leaning over the water tank to perform some task, was cut and killed by the "shrapnel" formed when the water tank burst. - ED.

Chester New York Police Dept. Water Treatment Plant Explosion - King Tract Development [PDF] Town of Chester, NY Police Department, - retrieved 2021/04/19 original source: https://local.nixle.com/alert/4894709/

At 6:30PM on Tuesday, the Town of Chester Police responded to a report of an explosion in the King Tract development off of Laroe Road. Residents in the area were reporting that they had no water. It was determined that the water treatment plant for the development had exploded. Chester Fire Department responded to the scene and were assisted by Orange County Fire Investigators. No evidence of criminal activity was detected.

The water holding tank is pressurized by a compressor to send water to the residences. Preliminary investigation reveals that the tank failed and the internal pressure blew the end of the tank off and through the attached treatment building, completely demolishing the building. The water system that serves the area is privately owned by 473 West End Realty Corp. The water system owner has indicated that drinking water will be available to the residents from a water tanker later today.

Fox News "Two Killed From 300,000 Gallon Water Tank Explosion" Fox News, Tel: (888) 369-4762, April 07, 2011 - retrieved 2021/04/19 original source: https://www.foxnews.com/us/two-killed-from-300000-gallon-water-tank-explosion

The victims were in the midst of repairing a pump that filled the tank inside an adjacent concrete block building. The force of the water from the explosion caused the building to collapse, MyFoxTampaBay.com reported.

HeatingHelp.com, "Fatal Airing up of Water Tank", reported by Jughne, September 2016 - possibly anecdotal, no corroboration found, retrieved 2021/04/19 original source: https://forum.heatinghelp.com/discussion/158963/fatal-airing-up-of-water-tank

Karpen, R.J., "Investigation of a Water Pressure Tank Explosion", Minnesota Department of Health, Mankato MN, October 1940, retrieved 2021/04/19 original source: https://awwa.onlinelibrary.wiley.com/doi/abs/10.1002/j.1551-8833.1940.tb19589.x

On December 14, 1938, the water pressure tank of the municipal water supply of Bricelyn Minnesota exploded, wrecking the pump house and tank. The explosion occurred at 1 AM just as the pressure gauge indicated pressure nearest 60 pounds and the pump was about to shut off. The possibility that the zinc lining in the pressure tank was a contributing factor to the explosion was indicated in an investigation report conducted by the Minnesota Department of Health.

The Bricelyn water supply, prior to this explosion, was obtained from a drilled well from which the water was lifted by means of air and discharged into a small receiving tank. A centrifugal pump was used to force water from the receiving take into the pressure tank and distribution system. This pump had a rated capacity of 250 gpm, and was designed to operate up to a maximum head of 60 psi.

It was the practice of the operator to maintain the water level in the tank at about 4 in. above the center. This he accomplished by pumping at approximately two-hour intervals from 7:00 AM to 3:00 PM, at 6:00 PM, 8:30 PM, and at midnight. The daily consumption of water was about 18,000 gal. The pressure tank, 8 ft. in diameter and 36 ft. long, had been in service for 36 years. It was provided with a pressure relief valve which when tested opened at a pressure of 66 lb. psi.

Eight or ten onths prior to the explosion, a leak developed in an end seam at the bottom of the tank. After the tank was drained and inspected it was found that the portion of the tank which had been in contact with the water was petted and corroded. It was then reconditioned by welding the defective same and it"s interior surface was coded by spraying it with molten zinc.

TOMBALL, Texas A worker was killed Tuesday after a water storage tank exploded near Tomball. It happened at the Salem Lutheran Church, at Lutheran Church Road and FM 2920.A spokesperson for the church said the injured man was working on the 20-foot-tall tank when the blast happened. The force of the explosion caused the worker to fall and ripped the lid off the tank. - original source https://www.khou.com/amp/article/news/worker-killed-in-church-water-tank-explosion/285-341096970

Yannaccone, John R., P.E. "PRESSURIZED WATER TANK EXPLOSION" DJS Associates, John R. Yannaccone, P.E., Senior Mechanical Engineer with DJS Associates, Inc., Email: experts@forensicDJS.com Tel: 215-659-2010.- retrieved 2021/04/19 original source: https://www.forensicdjs.com/blog/pressurized-water-tank-explosion/

A worker was operating a system used to supply water from a tank mounted on a utility vehicle. Instead of using a pump, this system used a 120-gallon water tank, which was pressurized from a compressed air cylinder. The air pressure pushes water out of the tank, referred to as an “air over water” system. While operating the system, a worker near the vehicle was blown 20 feet from where he was standing. He sustained severe blunt force trauma and died as a result of his injuries. Photographs from the incident showed that the end of the water tank dislodged from the main portion of the tank.

Expert Analysis: An inspection of the system revealed that the tank was in good condition, with no signs of corrosion or other damage. The 120-gallon water tank had a label indicating the maximum working pressure for the tank was 75 psi and must be equipped with an adequate size pressure relief valve; however, there was no pressure relief valve in this system.

... it was determined that the pressure regulator failed during operations, allowing air to continuously flow into the tank. The lack of a pressure relief valve allowed the tank pressure to increase until the tank failed.

Watts 53 pressure relief valves in 1/2-in NPT and 3/4-in NPT. Model 53L includes a test or relief lever. Quoting from Watts® product literature for this product:

Series LF530C Lead Free* Calibrated Pressure Relief Valves are used in commercial, residential and industrial applications to protect against excessive pressure in systems containing water, oil, or air.

Series LF530C has a calibrated adjustment feature for setting the valve to the required relief pressure, and is ideal for by-pass thermal expansion pressure relief (not ASME approved).

Watts 30L Pressure Relief Valves for Well Systems, with test lever. These valves, intended for protection against excessive pressure in well water systems, are designed for pressure relief only [compared with pressure and temperature relief valves that should be used on water heating equipment -

Series 30L Pressure Relief Valves for Wells are used to protect against excessive pressures in well systems. It is not diaphragm actuated and is used for pressure-relief service only.Series 30L consists of a bronze body construction with NPT threaded male inlet and NPT threaded female (drain) outlet connections, stainless steel spring, and test lever. Standard Pressure Setting: 75psi (5.17 bar), Optional Settings: 100, 125, and 150psi (6.9, 8.6, and 10.3 bar). - Watts®

These valves are installed as an auxiliary bleeder pressure relief valve to provide relief of increased water pressure due to thermal expansion, and they are typically installed on a hot water supply pipe downstream from the water heater and over a laundry sink or drain. Watts points out in their product literature that these valves are also installed on cold water piping.

Standard water tank pressure relief valves are sold at plumbing suppliers and are pre-set with a "safe" pressure for most home water tanks, provided that the water tank, piping, and controls are properly installed and adjusted.

A professional plumber would select and install a water tank pressure relief valve that opens to spill water and relieve pressure at a point well below the rated burst pressure of the tank.

The burst-pressure of a water tank, provided it"s undamaged and properly installed, should be well above the opening pressure on the tank relief valve. But to choose a specific valve matched to your water tank, you should consult the manual for your water tank and pump and their manufacturer to be sure you"ve got the right part.

Dan I"m not entirely clear on what is your situation, but if you have a 1" diameter pressure relief valve it is unsafe to downsize its discharge to 1/2" -

I have a well water 1 inch relief valve with a 0.5 inch output. It is leaking and would like to buy another, but cannot find one. Also my water tank holds 50 gal and the tank pressure should be 40psi.

Allen we dont" want the valve to spit water; I suspect that the water level is too high in the tank OR the float is sticking and not closing the valve OR there is dirt on the valve seat.

My bladder type tank has an air release valve similar to a schrader valve. Lately in addition to expelling the air when the tank is filling, I"m getting a "spit" of water or condensation with it. Is this something to be concerned with? I"m in the humid Houston area, so I guess it could be condensation, but I also don"t want that dripping down my tank and eventually corroding it.

Jon, Definitely, I"ve heard various valves in plumbing systems make a horrible screeching sound if the pressure and flow rate happen to be just right (or wrong).

But you should not be having a discharge from a pressure relief valve on a water supply system - the valve should only open if the system is at abnormally high (and unsafe) water pressure. So if there is no water discharge from the valve, I"d look elsewhere.

Can a bad pressure relief valve give off a high pitched squeal? I have such a noise coming from the area of my well equip, but not on a regular or constant basis.

WATER TANK PRESSURE RELIEF VALVE at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Watts Corporation, Series 53 Pressure Relief Valves, for commercial and residential applications, publication ES-53 1010, Watts Corporation, 815 Chestnut St., No. Andover, MA 01845-6098; www.watts.com and Watts Corporation in Canada: 5435 North Service Rd., Burlington, ONT. L7L 5H7; www.wattscanada.ca.

Access Water Energy, PO Box 2061, Moorabbin, VIC 3189, Australia, Tel: 1300 797 758, email: sales@accesswater.com.au Website: http://www.accesswater.com.au/

Australian supplier of: Greywater systems, Solar power to grid packages, Edwards solar systems, Vulcan compact solar systems, water & solar system pumps & controls, and a wide rage of above ground & under ground water storage tanks: concrete, steel, plastic, modular, and bladder storage tanks.

TECHNICAL REFERENCE GUIDE to manufacturer"s model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop Weldon & Associates

This article explains hot water thermal expansion that can cause leaks, drips, or discharges from pressure relief valves, temperature/pressure relief valves, or TP valves found on heating boilers, water heaters.

Watch out: a dripping or frequently spilling T&P valve is dangerous because those very leaks can eventually cause the valve to clog and then to fail to open when it should.

See HOT WATER PRESSURE EXPANSION RATE - for an explanation of just how much pressure increase to expect when heating water. In explaining why the relief valve on a water heater may be dripping, American Water Heater Co. [1] explains:

Note: While a 125 psi pressure relief valve on cold water supply piping is fine to protect piping from rupturing, if building incoming water pressures are too high, rather than relying just on a relief valve (wasting water) we prefer to install a pressure reducing/control valve at the building entering water supply piping. Limit incoming water pressure to 60 psi at a typical one or two story residential home.

Watts (2011) suggests two methods for testing for thermal expansion of hot water as the cause of a TP valve drip. The text below is adapted from that source.

If the TPR valve is leaking due to thermal expansion of hot water, simply opening a water faucet or fixture anywhere in the plumbing system will immediately stop the drip.

That"s because opening the hot water faucet reduces the system pressure back to normal operating levels - we are no longer heating water in a "closed" piping and tank system.

Why would opening either a hot or cold water faucet work? Because when no water is running, the entire plumbing system is "closed" - unless there is an expansion tank already installed on the hot water heating system to accommodate thermal expansion, heating water in the water cylinder (water heater for Yanks) causes an increase in system pressure.

Install a pressure gauge on a convenient hose bib such as at the washing machine hook-up or if weather permits, outdoors. Install & use the pressure gauge to monitor system water pressure over at least a full 24-hour period. You don"t have to sleep by it.

If you select a pressure gauge with a re-settable "telltale" needle, the gauge"s re-settable indicator will indicate the highest pressure that has been reached by the water system since the water pressure test gauge was installed.

SeeMEASURE WATER SYSTEM PRESSURE & PRESSURE MAXIMUM for tips on how to make or buy an inexpensive recording-type water pressure test gauge for this purpose.

where we describe both hot water expansion tanks and hot water expansion relief valves designed to handle thermal water pressure increases and thus to stop dripping TP valves.

Watch out: get advice from a licensed plumber and your local water supplier. Never remove or plug a leaky pressure/temperature relief valve on a water heater - doing so risks dangerous or even fatal

See RELIEF VALVE LEAK DUE TO EXPANSION TANK where in a series of steps a homeowner figures out that a leaky TPR valve is due to the failure of the internal bladder of an expansion tank attached to the boiler.

If the building water pressure gauge reading is ever found at 80 psi or higher, you will want to install a water pressure regulator at the point where water supply enters the building.

If your building already has a water pressure gauge installed, it may be defective or it may be set too high. The articles listed just below discuss how to adjust a water pressure regulator:

An alternative to installing or changing a water pressure regulator when building water pressure is occasionally 80 psi or higher is the installation of an expansion tank to temporarily absorb that pressure increase.

Proper use of an expansion tank can help avoid unnecessary opening of the pressure/temperature relief valve on a hot water heating tank or a hot water heating boiler.

You go through alot of effort to explain how heated water expands and the resulting increase in pressure. All that is well and good for theory. In a domestic (North American) water supply system, to the best of my knowlege there is nothing to prevent the expanding water/pressure from the hot water heater from just backing up into the supply plumbing and hence the water pressure in the hot water heater would NEVER exceed the supply pressure. Or is there a required one way valve somewhere in the system I am not aware of say in the hot water heater?

Domestic water systems in most cities are required to have a backflow preventer or check valve on the system. So when no water is being run the system is in effect closed.

My original interest and intent was to show that the actual expansion in volume from heating water is actually very small. Nevertheless, on some systems, the water heater can cause enough of a pressure increase that some installations include a small water heater expansion tank.

Where expanding hot water pressure is causing trouble the common solution is the installation of a small expansion tank, usually on the hot water supply line above the water heater, though it could go almost anywhere so long as it"s not isolated from the heater by a shutoff valve.

Thermal expansion occurs as domestic water is heated. Left unchecked, the resulting pressure increase can cause relief valve discharge and other potentially hazardous conditions. Therm-X-Trol® expansion tanks absorb this expanded water, keeping water pressure at a safe level.

Water heater manufacturers and plumbing codes require the installation of an expansion control device if a backflow preventor, pressure reducing valve or check valve is installed in the domestic supply line.

Watch out: a leaky relief valve on a water heater, heating boiler, or any other closed vessel is dangerous. Leaks ultimately can lead to relief valve clogging, failure, and worse, BLEVE EXPLOSIONS. Beginning at RELIEF VALVE LEAKS we describe all of the causes of and cures for leaky relief valves or TP valves.

ANSI BS 7074-1:1989, Application, selection and installation of expansion vessels and ancillary equipment for sealed water systems. Code of practice for domestic heating and hot water supply (British Standard)

This standard covers the test methods and performance requirements applicable for waterheater supply shutoff valve with a thermal expansion control valves for use on closed plumbing systems.

This European Standard specifies, dimensions, materials and performance requirements (including methods of test) for expansion valves, of nominal sizes from DN 15 to DN 40, having working pressures 1) from 0,1 MPa (l bar) to 1,0 MPa (10 bar).Expansion valves are intended for fitting to the cold water supply of storage water heaters, having a maximum distribution temperature of 95 °C, for all energy sources.

Expansion valves do not control the temperature and alone does not constitute the protection required for storage water heaters. Expansion valves limit pressure, in the water heaters to what they are fitted, that is produced by thermal expansion of the water .NOTE : The use of the device specified in this Standard does not override the need to use controls (e.g. thermostats and cut-outs) which act directly on the power sources of water heaters.

"THERM-X-TROL® Water Heater Expansion Tanks", [web page] Amtrol,1400 Division Road, West Warwick RI USA 02983, Tel: 800-426-8765, Website: www.amtrol.com, retrieved 2017/01/08, original source: http://www.amtrol.com/thermxtrol.html

"THERMAL EXPANSION TANKS for POTABLE WATER, Installation & Operation Instructions" [PDF], Models ST-5 through ST-201V & Models T-5 through T-12, Amtrol, Op. Cit., retrieved 2017/01/08, original source: http://www.amtrol.com/media/documents/thermxtrol/9015087_06_16_Thermal_Expansion_Tank_IO_.pdf

the red-circled valve is a combination of cold water inlet shut-off valve and a drain intended to provide relief against excessive pressure in the water heater due to thermal expansion - as discussed on this page.

the red-circled valve is a combination of cold water inlet shut-off valve and a drain intended to provide relief against excessive pressure in the water heater due to thermal expansion - as discussed on this page.

Similar products manufactured by Watts are described at WATER HEATER THERMAL EXPANSION PRODUCTS - WATTS [PDF] https://inspectapedia.com/plumbing/Watts-Thermal-Expansion-Products.pdf

My hot water tank has a Thermal Expansion Control Valve installed on the cold water intake line (rather than an expansion tank). In the past 2-3 days, I have noticed that there is a small amount of water constantly draining out of this Valve/Tube.

The leakage is constant, even during/after a long hot shower, which presumably would drain a lot of the hot water out of the tank and temporarily stop any thermal expansion/condensation. It is important to note that the T&P valve on the water heater itself is fine, there is no leak or release of pressure/water happening there.

(Why else would it still leak when the hot water tank is being drained and cold water is entering the tank?). Wondering if anyone has any thoughts on this? I"m pretty sure I should be calling in for a repair, but unsure how urgent. (Am I at risk of a BLEVE explosion given the leak is constant, even when the tank should not be up to temp/pressure and even the pipe between the tank and the valve feels cold?).

It is possible on SOME water heaters to set the temperature above 210°F (99°C) but in my experience that would be unusual - you"d have probably scalded everyone using the hot water system.

1. It is already telling us that (usually) there is an unsafe condition such as pressure too high (water tank can blow up in a BLEVE explosion) or temperature too high (someone can be scalded - burned)

2. If it"s dripping just because the valve itself is old and defective the risk is that scale clogs the valve, it stops relieving, and then you"re missing a critical life-safety device.

the hot water heater has been shut down about one year , I lit the polite then went back a few hours later when I noticed the pressure relieve valve was spraying water out. so I shut the gas off. not sure what"s going on. ?

Continue reading at HOT WATER EXPANSION TANKS for a solution to thermal expansion leaks at relief valves on water heaters, or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

THERMAL EXPANSION TPR VALVE LEAKS at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

[1] "Residential Electric Water Heater Installation Instructions and Use & Care Guide", American Water Heater Co., October 2001, American Water Heater Co., Johnson City, TN, [manufacturer of residential & commercial water heaters, also manufacturer of Polaris/Commercial water heaters], Tel: 800-999-9515, web search 1/12/2012, original source: americanwaterheater.com/support/manuals/res-elect.pdf [copy on file] [Technical review requested 1/25/2011]

[3] Pounds of lime deposited vs. temperature and hot water usage: see Purdue Bulletin #74 (also provided by A.O. Smith in the article below). Purdue"s chart shows the number of pounds of lime deposited per year as a function of the water usage in gallons per day, with an assumed 10 grains of water hardness.

[4] "When, Why, and How to Remove Water Scale from Tank Type Glass-Lined Water Heaters (for non glass-lined tanks, consult water heater manufacturer)" PDF provided by A.O. Smith Water Products Company - hotwater.com/lit/training/4800r9.pdf 800-433-2545 - 01/07/2009.

[6] A.O. Smith"s Form No. 4778* All about Deliming Coil-Type/Tube-Type Commercial Water Heaters and Hydronic Boilers *Normally supplied when ordering Part No. 4930 Motorized Deliming Pump Kit

[7] "Building Owner Water Heater Safety Notice", Building Department, City of Colleyville TX, web search 09/24/2010, original source: http://www.colleyville.com/dmdocuments/Building%20

Water heater safety is imperative to the occupants of a building or structure. If improperly installed, water heaters can be detrimental to the structure, as well as being potentially fatal to its occupants. The proper installation of a water heater is so important that according to Texas State Law all water heater installations must be inspected by a state licensed plumbing inspector.

TECHNICAL REFERENCE GUIDE to manufacturer"s model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop Weldon & Associates

Your water heater makes life convenient. Hot baths and showers, warm water for dishes, and washing clothes – it’s all become a part of daily life for many. However, a malfunctioning hot water system isn’t just frustrating, but a danger as well when highly-pressurized tanks become involved. Upon troubleshooting your water heater, you may find that it’s your water heater pressure relief valve(TPR valve)that’s giving you a problem.

Fortunately, this is a fairly common problem and is generally quite easy to identify when you know the right signs to keep an eye out for.Here’s how to tell if a pressure relief valve is bad.

Your gas or electric water heater’s temperature and pressure valve (or T&P valve) is a crucial safety feature that a professional should routinely inspect.

As the name suggests, this part helps to relieve pressure on the water tank when necessary. When the water cools and heats, it contracts and expands over and over again, at times placing a great deal of pressure on the inside of your hot water tank.

In most water heaters, the superfluous water will travel back up the cold water inlet and back to the home’s water supply. However, in homes with valve checks or one-way valves and pressure regulators, this is impossible, meaning the water stays in the tank and pressure continues to build. The pressure relief valve lets a bit of this water leak out when necessary in order to keep this pressure inside the tank at safe levels.

Before you can check your valve for damageor learn how to tell if a pressure relief valve is bad,you’ll have to find it. The valve in question is a small pipe that extends away from the tank in a downward direction.

Since it’s a rather simple, straightforward part, issues with a pressure relief valve are typically easy to spot. There are five telltale signs to keep an eye out for if you’ve been experiencing issues with your water heater.If you want to know how to tell if a pressure relief valve is bad, watch for these common signs:

Flooding:Water should never be gushing from the valve. If this occurs, turn off the water supply immediately and contact your plumber for a proper assessment and fix.

Excessive noise:If your hot water heater is rattling or emitting a high-pitched whistling noise, it’s likely the sound of steam trying to escape the tank, which is a sign of far too much pressure pressing against the inner walls. This means the relief valve isn’t doing its job and may need replacing.

Debris in water:Pressure relief valves do go bad, and debris can be one indication of this problem. If you find excessive debris or rattling continues after you turn off the water and attempt to clean your valve, you may be dealing with significant corrosion. The part may need to be replaced, and a plumber should be called for a full evaluation of your tank.

Ruptured tank:Water should never leak from the tank itself. If you’ve found water coming from the seams of the water heater, you may be dealing with a tank rupture. This occurs after pressure buildup has been left untreated for a long time and is a direct symptom of the valve being unable to release excess water properly.

Leaking:The pressure valve should leak while doing its job, but it shouldn’t be leaking a considerable amount of water and shouldn’t be doing it often. If it seems like the valve just never stops leaking, you’re likely dealing with a problem. It could mean that your water heater is very frequently overheating or that your water heater valve is simply not holding in pressure as well as it should.

As you can see, pressure relief valvesdogo bad from time to time. Now that you know how to tell if a pressure relief valve is bad, you may want to know how to test the valve.

Are you still unsure if your TPR valve needs replacing? Before you go scouring the internet for an “emergency plumber near me now,” consider performing a test. You can test your temperature and pressure relief valve to ensure that it’s working properly—and, of course, safely. Follow these steps:

Take Off the Drain Pipe:Remove the drain pipe from the valve; you may require a plumber’s wrench to do this. Keep a heat-safe bowl or bucket below the line.

Check For Water:Ensure that only a tiny stream of water drains from the tank and into the bucket. If there’s no water flowing from the tank, it’s time to replace the valve.

If you’ve experienced any of these issuesdiscussed above, then yes, it’s likely that your pressure relief valve is bad.Pressure relief valves do go bad for several reasons, butfortunately, the fix is easy, especially when you have a group of knowledgeable professionals on your side.

When you need help with your water heater and decide to comb the internet for a “house plumber near me,” remember that you can reach out to the Whipple Service champions for a wide range of emergency plumbing services.

However, the job doesn’t end at the fix. To ensure your gas water heater is still in good working condition and ready to face the challenge of keeping up with daily hot water needs,contact Whipple Service Champions. Schedule an appointment to have your valve inspected and replaced and get your water heater back to normal again in no time.

If there’s a leak at your temperature and pressure relief valve, first test to ensure it’s operating correctly. If it isn’t working properly, replace it.

If the T&P valve is operational, check to see if you have a pressure-reducing valve, usually near the main water shutoff. If a pressure-reducing valve or other form of check valve is present, you’ll need to add a potable expansion tank.

Q: Help! My hot water heater is leaking. After mopping up, I see more water starting to puddle but I can’t tell where it’s coming from. Do I need to call a plumber, or is it possible for me to fix the leaking water heater myself?

A: Water heaters can leak due to a number of problems, including loose valves, excessive pressure in the tank, or issues with the pipes that connect to the unit. And if your water heater is more than 10 years old, the leak is likely age-related—if that’s the case, it may be time to replace it. So while you might eventually need to call a plumber, depending on the location of the leak, there could be a simple DIY solution. Keep reading to find out the immediate steps to take, and then how to pinpoint the leak and remedy the problem.

If it’s a gas water heater, it will have a dial or an On/Off switch near the spot where the gas line connects. If it’s an electric water heater, locate your home’s electric service panel, and turn off the breaker labeled “Hot Water Heater” by switching it to the “Off” position.

You’ll find two plumbing pipes attached to the top of the water heater. One is the hot water pipe that supplies hot water to your faucets and the other is the cold water supply line. Only the cold pipe will have a shutoff valve; turn that valve to the Off position to stop cold water from flowing into the tank.

Water heater leaks often start out slow, just drip by drip, so it can be difficult to tell where the water is coming from. Check for wetness by running your fingers or a tissue around these three likely locations:the fittings on the pipes above the water heater,

around the temperature and pressure relief (TPR) valve. The TPR valve is located on the side of the tank, and it should have a copper tube that extends out a few inches and then turns downward to the floor. The bottom of the tube is open, and you should check there for wetness as well.

If water is coming from the cold water supply line and the hot water pipe, you may be able to stop the leak by tightening a loose-fitting with a wrench. This is possible if flex pipes, such as these 12-Inch Fluidmaster Braided Stainless Steel Connectors (available on Amazon), are attached between the water heater and your home’s main cold and hot water lines. Flex pipes are a common configuration, and they attach just as a garden hose would attach—a straightforward DIY fix for many homeowners. If the water pipes are solid copper, however, you will need to have a plumber repair it, because copper connections must be soldered in order to seal.

The pressure in a water heater tank depends on two things: the temperature of the water and the pressure of the water coming in from the cold water supply line. When the pressure in the tank builds to an unsafe level, the TPR valve, sometimes called a pop-off valve, opens to release the pressure. This valve—at the down-turned pipe you located earlier—is a safety mechanism designed to direct a scalding spray of water to the floor rather than the face of someone standing nearby.

If the leak is coming from around the valve itself or out of the bottom of the pipe, it could indicate that the water in the tank is too hot. Many manufacturers sell water heaters preset for 140° Fahrenheit, but the Department of Energy (DOE) suggests that 120° Fahrenheit is hot enough for most houses. The temperature control knob may or may not list actual degrees, but if not, turn it from “High” to “Me