How to Install Water Heater Heat Traps – DIY Tips

Heat traps for water heatersHeat traps

What are the water heater heat traps, and how do they work? Are they worth the extra effort and cost? Do they create problems, and what happens if you remove them? Installation and buying tips.

In this article:

  1. Energy usage and how to improve energy efficiency
  2. What are the heat traps
  3. How do heat traps work
  4. Do I have to install heat traps
  5. DIY tips to prevent thermosyphoning
  6. How to install water heater heat traps
  7. Can I remove heat traps
  8. Problems caused by the heat traps

Energy usage and how to improve energy efficiency

According to some studies, the total energy usage of water heaters in residential homes is close to 20%. So if the heater's efficiency is higher, better for you, because you will spend less on heating. If you have a water tank heater installed in your home, it is important to understand that standby heat loss is one of the main reasons you could have high energy bills.

As the heat is mainly lost through the flue vents (gas type), tank walls, and pipes, insulating the heater to operate efficiently is advisable.

The best way to eliminate or reduce wasted energy is to install an insulation blanket on the water heater, insulate the pipes and install the heat traps (if they are not already built-in).

What are water heater heat traps?

Heat traps are small devices designed to reduce heat loss through the heater's inlet and outlet pipes. The most popular types come with floating balls and plastic inserts with flaps.

When the hot water is not drawn from the tank, the heat, which resides inside the tank, could exit the cold (inlet) and hot (outlet) piping due to natural convection (the heat moves from hot to cold). This is also known as thermosyphoning, and it is the main reason for water circulation when the heater is not in use. Once the heat traps are installed, they will prevent or reduce water circulation.

How do heat traps work?

As mentioned, heat traps prevent heat loss and circulation. Using the example of the ball-type traps, water pushes the ball into the upper position so water can move freely from the tank to the fixture when the hot water tap is open.

And if there is no water pressure, the ball will be sitting in its lowest position, preventing heat dissipation through the pipe (ball type). The flapper-style does the same thing; it opens when the heater is in use and closes when the unit is not operating.

While the nipples with the floating balls could produce noise problems, the flapper style inserts are becoming the favorite types among plumbers as it eliminates such issues.

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Do I have to install heat traps on a water heater?

Heat traps are not mandatory but are recommended. Most of the new models have them already installed. If the heat traps are not factory-installed, manufacturers and experts recommend installation in retrofit applications where the kits are available either from the heater's manufacturer or any plumbing/HVAC store.

Besides reducing the standby heat loss, heat traps are also helpful when connecting two different metals (for example, copper pipe to a metal tank). Those are known as dielectric heat traps, and they reduce the risk of corrosion between two metals.

Dielectric heat traps have a metal body threaded on each end while its inner part is covered with the thermoplastic lining, preventing galvanic corrosion.

DIY tips to prevent thermosyphoning

You can also make your own heat trap to stop the self-circulation and heat dissipation by bending the hot pipes downward and making a "U" shape pipe, also known as a gooseneck loop.

It is recommended to bend the pipe at least 20 mm.

Such an idea can be used to protect the thermostatic mixing valve when the valve is subjected to a higher temperature, especially when installed close to the heater and when not in use for some time.

When combining the water tank storage and a boiler, make the heat trap in a way to prevent hot water from circulating back into the boiler when idle. What will enhance unwanted circulation is if the boiler is installed above the water storage tank.

How to install water heater heat traps - Things to consider

Heat traps installation is a DIY home project. This is not hard to do, and it doesn't require any special tools or skills.

The connection doesn't have to be soldered if you install a nipple with the floating ball and threaded ends on both sides. Only if you are retrofitting, you might have to cut an existing pipe and provide more space.

Some experts recommend draining a few gallons of water before installing and releasing the pressure on the T&P valve. But first, turn the heater off.

Use the adjustable wrench to remove the old nipples from the heater on one side and the plumbing connector on the other.

While putting in new ones, use some Teflon tape or joint compound to cover the exposed thread to make a better seal and provide additional insulation between the two metal parts.

Make sure to install them, so the arrow is pointing in the direction of the water flow.

For this work, you will need less than an hour.

As mentioned before, you can also make your own "heat trap" - a gooseneck loop.

Can I remove heat traps?

If your gas or electric water heater is equipped with ball-type heat traps and the noise problems such as "ticking," "clicking," or "tapping" comes often, some plumbers recommend removing the ball from inside. If you have sprinklers and water pumps installed, frequent pressure fluctuation will cause the ball to rattle, resulting in annoying noise.

This problem can be eliminated by installing flexible disk-type heat traps, as found in some water heaters from the Bradford White manufacturer. These are made of plastic, making them easy to install by pushing into the top of extension pipes, and such installation eliminates the noise and makes the dielectric connection.

Problems caused by the heat traps

Heat traps, like other components, could break and fail.

Improperly installed, heat traps could develop rust, sediments, or leaks. They could also reduce or stop normal water flow if the valve is not installed correctly.


Buying and installing heat traps on water heaters is not expensive, time-consuming, and doesn't require any special tools or knowledge. Just follow the guide or a video.

They are a simple and cost-effective solution for reducing standby heat loss, unwanted circulation, and valve exposure to a higher temperature, reaching savings of up to 50% and longer valve life.

When installed, they can operate as union valves, allowing easy removal and replacement of your heater.

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