Hot Water heater pressure relief valve leaking or dripping: is it Dangerous? (How to FIX it!)

Every home has a boiler that heats the water for showers and toilets. The boiler operates at a certain pressure, which is needed to get the water flowing. If a boiler operates at a higher pressure than is required to operate it, pressure will build up in the system.

This is known as pressure build-up and it can lead to expensive repairs or even let your tank explode. To avoid this, there is a pressure release valve that removes water to release the pressure.  This article will cover what a pressure relief valve is, its purpose, and how to check if yours is leaking.


What is a pressure relief valve and how does it work?

The pressure relief valve is a safety mechanism on hot water heaters that allow excess pressure to escape safely, preventing expensive damage from high pressure. Hot water heaters work by heating water to a certain level, then sending it through pipes to your home.

If the pressure in the pipes is higher than the set pressure that the heater is designed for, the valve will open, allowing the extra pressure to escape back into the water supply. If the pressure is too low, the valve will close and stop water from flowing through the pipes. This water might not be clean so you should clean it up when you see it.

Water pressure can increase in a water heater when it is heating up water.

The water pushes open a valve and it can escape from the water heater without doing any damage. The pressure release valve opens up if there is a certain water pressure limit (psi) that has been met. It is a mechanical part so it doesn’t need software or electricity. It has to be adjusted to the size of your pipes.

Some come with a gauge and this can make it easier to see if there is a problem with the water pressure. They are generally made out of metal. Some of them have plastic parts but this is not recommended as these are more fragile. Check your local code to see what is required in your area. This is a part that you don’t want to save on as it can save you a lot in the long run given that it can save your water heater in some situations.

How to check if your pressure relief valve is leaking

If your pressure relief valve is leaking, you’ll notice water dripping from the valve. There can also be water buildup on or below your water heater. It is possible that your water heater gives an alert on its display. Water heaters have advanced sensors and can diagnose problems. If the error code is not clear, you can Google the name of your water heater and the error code to get a better idea of what is going on.

Small or irregular drips are often not a problem. If there are regular drips, you might want to contact your plumber to see what is going on.

The pressure release valve can break. This can be dangerous as your water heater has no way to release the pressure and it can break. Most pressure-release valves have a tester. This can be pushed to see if it will release water. Some plumbers recommend that you do this from time to time to check if your valve is still working. Others are more cautious about recommending this as this tester is often quite fragile and can make the pressure release valve fail.

The water from the pressure release valve often goes into a drip pan or a special drain. This makes sure that you don’t have water damage. It is not that uncommon that the valve leaks some water and it is better to remove it. The drawback of a drain is that it can be harder to notice a problem with the valve. You can often hear the water flowing but you don’t see wet spots.

If there is a big problem, most modern water heaters will simply shut off. This makes sure that they don’t get damaged. This is why you have to pay attention to the error codes on your water heater. Don’t simply restart it as this can create a lot of damage. Water heaters can last more than 10 years and it would be a shame to break them earlier because the water pressure was too high. 

When to Change a leaking pressure relief valve

A pressure relief valve should be inspected and replaced every few months. Inspections are best done during a routine service visit, but you can also inspect them yourself. If you notice problems with the valve, it should be replaced immediately. 

Plumbers can change a valve in under an hour. This piece is quite cheap and it should be replaced when you are unsure if it is working properly. It is an important safety device and should be treated as such. Common problems include the buildup of calcium, problems with plastic parts, or improper installation.

You should get a licensed plumber to get this installed as it is an essential part of your plumbing system. Water heaters are quite expensive and water leaks can cause a lot of damage. Therefore it is important that the pressure release valve is properly installed and maintained. It is a part that most people don’t think about but deserves a lot of attention.  

What are the costs of a leaky pressure release valve?

Water heaters can often be fixed. It might be needed to open it up though. Plumbers might charge anything between 200 USD to 500 USD, depending on what parts are needed.

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If they have to replace the water heater, the price can run higher, from 2000 USD to 5000 USD. If you have an older water heater, it might be worth replacing it instead of fixing it. Water heaters often last about 10-15 years. Once it is hitting this time limit, you can look at replacing it. 

The water that is leaking can contain acids so you have to be careful when you handle this. If it is leaking in your garage or cellar, you have to wear gloves and protective equipment when you clean it. This water can build up pretty fast. For this reason, you have to be careful that it doesn’t flood your house. It can cost a lot of money to get this fixed. 

You can often hear the water running so it is quite noticeable. You can also use your hand to feel for wet spots if you think that it is leaking.  

Adding a drip pan under your water heater can be a great idea. This makes sure that you can collect the water instead of it flowing on your floor.

Do you have to replace your boiler when this happens: how to fix

Check the error code on the display of your water heater. You can find more information about this in the manual of your hot water heater. This often indicates if something is wrong.

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You can also take a look at the water pressure gauge to see if the water is under too much pressure.

If these things don’t solve the problem, you should contact a plumber to get your system checked. In most instances, it can be fixed but sometimes you will have to replace your water heater.

If your boiler is leaking water, you may have to replace it. Most boilers are designed to handle a certain amount of water before they need to be replaced. However, if your boiler is leaking water, it means that the pipe leading to the boiler is corroding and has started leaking water.  

Summing up

A pressure relief valve is installed on hot water heaters to allow excess pressure to escape safely, preventing costly damage from high pressure. If you notice water leaking from the valve often, it might be time to get a checkup on your water heater. Small or irregular drips are often not a problem. The water is often dirty though so it should be cleaned thoroughly. Adding a drain makes this easier but can make it more challenging to detect that the valve is dripping water. 

This is a part that you don’t want to save on given that it has to last a long time and can avoid expensive repairs.