Plumbing, Water Heaters

Do I Need a Heat Trap On My Water Heater?

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Hubert Miles

Updated on

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A water heater is one of the most simplistic household electronic gadgets. But you might have heard some people complain that it consumes a lot of electricity. It could be true or false depending on whether it has a heat trap. Do you need a heat trap on the water heater?

It is imperative to have a heat trap on the water heater. The component is fundamental in reducing heat loss by up to 60%. A heat trap on the water heater is thus crucial in reducing electricity consumption. Consequently, it saves on your electricity bills. 

While heat traps work under a simple principle, there are many critical hacks about the component that you need to know. Keep reading for further enlightenment on heat traps. 

Do I Have To Install Heat Traps On a Water Heater?

It is not a mandatory requirement to have heat traps on a water heater. Nonetheless, they provide several upsides, and thus it is recommendable to install them. If you are using a modern water heater, there’s a high chance that it already has a pre-installed heat trap. 

You can quickly locate the factory-installed heat traps. Most are at the top of the water heater. Also, you will identify them by their color codes.

However, if your heater lacks a pre-installed water trap, consider installing one to solve the aforementioned thermosiphon conundrum. The above steps should assist you in the installation process.

So why do experts insist that you need to install heat traps?

There is a myriad of benefits. They include:

  1. First, they will reduce heat loss when hot water in the heater is on standby mode. Heat traps will minimize heat by approximately 60%.
  1. Also, they are referred to as dielectric heat traps. The naming is due to their property of facilitating a strong connection when connecting a pipe to a tank. For instance, when combining a copper pipe with a metal tank, the dielectric heat traps are significant in reducing the chances of corrosion. Without them, the metals can corrode at the junction.
  1. The heat traps are also good in cushioning the heater system from the galvanic and stray current of the circuit. Nonetheless, you need to install the heat traps to facilitate this process carefully. For instance, you must isolate the copper pipes from direct contact with the tank via silicone pads.

How Do Heat Traps Improve Energy Efficiency? 

In most residential homes, water heaters usage contributes about 20% to the total electricity usage. Hence, if the water heater has high efficiency, you will reap more to save on electricity costs.

It would be best if you thus solved the standby heat challenge that is synonymous with water heaters. There are many ways by which heat is lost. Nonetheless, heat loss by thermosiphon is more familiar with heat traps.

With a heat trap, you will improve energy efficiency and thus minimize the percentage of energy usage.

What are Heat Traps?

Typically, a heat trap is a device designed to control heat loss at the inlet and outlet of a water heater. 

You’ll find two types of heat traps in the market. First, there are those with floating balls. Secondly, there are heat traps made of plastic inserts with flaps.

Heat traps take care of the conventional currents nature of water. When the water in the heater is heated, it will be cooled by the cold water, thus resulting in heat and energy loss. A heat trap solves this problem.

Ideally, natural convection occurs through the process of thermosiphon. It is a passive process that does not require any external force and will always happen with no heat traps.

The process happens when the hot water in the heater is not turned on. When you install heat traps, they prevent the natural convection motion. Hot water in the system thus retains its heat by not mixing with the cold water in the tank.

Consequently, energy and electricity are conserved.

How Does a Heat Trap Work?

Heat traps work by taking advantage of the thermal convection principle. Also known as goosenecks, the conventional heat traps separate hot water from cold water. Therefore, no heat is lost via convection.

When water gets hot, it will rise while cold water sinks. The goosenecks heat trap facilitates this process. It forms a u-shaped dip on the pipe, thus trapping hot water on the upper side of the loop. The cold water will subsequently pass the loop and enter the tank.

Although modern heat traps are pretty different in structure from goosenecks, they operate using the same principle. The heat traps are called nipples and are situated at the entrance or exit of the tank.

Both the entrance and exit have a ball to control the opening of the pipelines. There is a Teflon ball for the hot water outlet, while on the cold water inlet, you’ll find a polypropylene ball.

When the system is in standby mode, the balls rest on their location, thus preventing heat loss via convection. Conversely, on turning the hot water on, the balls open, allowing the flow of water. When you turn the tap off, the balls return to their rest positions, preventing hot water from moving to the tank.

Therefore, energy is saved by blocking heat transfer from the hot water to the cold water.

How Do You Install a Hot Water Heater Heat Trap?

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Installation of a heat trap is a straightforward process that should not consume much of your time. First, buy a nipple kit. You can find the nipple kits on online platforms or even in typical hardware stores.

Consider installing reputable heat traps such as Rheem or Bradford White, and they will serve you efficiently.

Here are the steps to follow during installation:

  1. First, turn off the power to the heater at the breaker panel. Ensure that you have indeed turned off the power by testing with a non-contact circuit tester. It is essential for safety. If you are using a gas-fired heater, shut the gas valve. You will also need to turn off the water supply to the water heater.
  1. Next, draw approximately 2 gallons of water from the heater. You can use a bucket or any other vessel. Remember to be cautious in this step as you’ll be dealing with hot water. Also, remove hot water from the water lines by switching on the faucets.
  1. Using a pipe wrench, remove the pipe supplying water to the heater. Disconnect this pipe both at the inlet supply and the hot water outlet.
  1. Once you disconnect the pipe, attach the heat traps to the hot water outlet and cold water inlet. The heat traps are coded to help in identifying the right one for the respective pipes. The cold water inlet heat trap will be coded blue, while the hot water heat trap will be red. It would be best to connect them according to the coding. Otherwise, the system will be dysfunctional.
  1. Next, reconnect the pipes back in position. Ensure you use plumbers pipe dope on the pipe’s threads for a watertight connection. Also, connect all the nuts in the same way that they were before disconnection. Reconnect the household faucets and turn the water supply on. Check for leaks after reconnecting the water heater power system.
  1. Fix the pipe leaks if present to minimize heat loss. Your heat traps should function effectively after the connection. The entire installation process should take less than an hour, especially if all the equipment is available.
  1. Alternatively, instead of the above installation process, you can create a gooseneck loop.

What Are The Common Heat Trap Problems? 

Like any other component, the heat trap nipples also have common problems. Nonetheless, a considerable number of these problems happen during the installation process. Others are caused by the manufacturer’s design of the components.

Here are some of the problems associated with heat traps:

  1. Many of the prefab goosenecks are prone to blockage or flow restrictions. Thus, some plumbers prefer to make their goosenecks by bending pipes rather than installing the manufactured ones. Such loops are less likely to block.
  1. Also, the loops could encounter problems if their diameter is larger than the recommended size.
  1. Nipples are neither spared from heat trap problems. You’re likely to encounter noise from the balls, especially in nipple heat traps with a recirculation loop. You can nonetheless avoid this challenge by installing flap models.
  1. Another common problem with heat traps is leaking. When poorly installed, they will most likely leak at the points where water enters and leaves the tank. You can nonetheless solve this issue by tightening the joints. Also, consider applying a Teflon tape at the joints to strengthen the connection.
  1. Also, you may have sediments or rust at the heat trap joints. Such matter will affect the operation of the heat trap.
  1. Lastly, the heat sink ball can wear out after some time, depending on the materials they are made of. When worn out, it will not continue resting on the valves as before, and thus the heat traps will be ineffective.

The solution to these challenges is the installation of flaps. Flaps heat traps, unlike nipples, are quieter. They are also less likely to inhibit smooth water flow as they are rarely stuck.

How Do You Know Your Heat Trap has Problems? 

You can detect when the heat trap is faulty without involving a plumber. The fundamental heat problem is heat loss by convection. Essentially, a heat trap aims to eliminate this challenge. Therefore, a faulty heat sink will have a thermosiphon challenge.

Therefore, to identify if your heat trap is dysfunctional, feel the cold water inlet pipe. If it is warm, then your heat sink is not operating at the top level. A warm or hot cold water inlet piper indicates that the heat trap valve is not preventing the hot water from moving to the tank.

If you encounter such a scenario, change the pipes or replace the heats sinks.

DIY Tips To Prevent Thermosiphon 

You do not have to operate on a high budget to fix the thermosiphon challenge. You can modify a heat trap using readily available materials.

Make a heat trap by bending a hot pipe to form a u-shaped loop. It will create a gooseneck loop which is commonplace in conventional heat trap systems. It will operate similarly to the prefab heat trap system by limiting heat dissipation and self-circulation.

The recommended pipe when forming this loop should be at least 20 mm.

The creation will be handy in the formation of a thermostatic mixing valve. When water is heated, it will be protected from interacting with cold water. Thus, if placed close to the heater, the loop will assist in keeping the water hot when the heater is in standby mode.

The design of your system will also be a vital determinant of the system’s performance. Especially when you intend to combine the heater with the tank, your heat trap should be perfect for preventing unwanted circulation.

Hence, position the water boiler at a higher position than the tank. It will enhance the performance of the loop.

How Do You Remove a Heat Trap?

You can simply remove the heat trap if it has challenges such as ticking or tapping noise caused by a worn-out ball. The recommended way of removing the heat trap is from the inside.

When you have a sprinkler connected to the heat trap system, the ball will likely produce noise. The noise is typically due to the pressure difference that this component places on the heat trap.

The solution will be to remove the balls. Alternatively, you can remove the entire heat trap system by replacing the existing line with another.

After removing such faulty heat traps, you need to fix a better kind that will not break easily. Consider having flexible disc heat traps. Many of such heat traps are made of plastic. Hence, they can be easily installed.

You only need to push them into the extension pipes. The result will be a dielectric connection. Also, you will have eliminated the noise issue that is commonplace with ball heat traps.

Alternatively, consider creating gooseneck loops when you remove the pre-installed heat trap. You can do this using the steps mentioned above, and thus you do not need to involve a plumber.

Final Thoughts 

Whether installing a heat trap on the water heater is a cardinal concern for many people. However, given the benefits that it avails, you shouldn’t hesitate to install the component. It will potentially save you up to 60% of your electricity costs by taking care of heat loss.

Additionally, the water heater system will be more efficient when you use a heat trap. Noteworthy, you do not necessarily have to install an expensive heat trap. You can create a gooseneck loop by creating a U-turn curve on the pipes. It will operate as effectively as a prefab heat trap.

Therefore, if you have a water heater, you need to confirm if it has a heat trap. If it does, check if it’s functioning well. If absent, consider installing one. You will reap big from the installation, especially in saving on electricity costs.


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Hubert Miles

I've been conducting professional home inspections since 2002. I'm a licensed Home Inspector, Certified Professional Inspector (CPI), Certified Master Inspector (CMI), and FHA 203k Consultant. I started to help people better understand the home inspection process and answer questions about homeownership and home maintenance.
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