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A Clogged Tankless Coil Can Cause Hot Water Problems

Tankless coils play a key role in the heat exchanger, which is where water is heated. Because the tankless coil is susceptible to buildup, it's possible that a clogged tankless coil is to blame for your water heater failure.

Check For A Clogged Tankless Coil

The high temperatures inside your water heater can cause the lime scale that's naturally in tap water to separate and cling to the inside of your heat exchanger.

As the coating gets thicker, it starts to act as a insulator, blocking the heating coil's ability to transfer heat. If not fixed, it could block your water heater from producing heat altogether — leaving you out in the cold.

How to check for a clogged tankless coil

  • Turn on the hot water faucet and watch the stream of water. Does the stream start to slow down? Some loss in water pressure could be normal, but if it slows to a dribble, it likely means you have a clog in the tankless coil.

  • Go to the tankless coil and look for the two water lines. There are two water lines that go into a tankless coil, one cold water and one hot. Turn on a hot water faucet. Being careful not to burn yourself, very carefully feel each line (do not just grab the water lines). Feel close to the coil on the hot water water line. It should be a toasty 160-180 degrees depending on the boiler temperature.

  • If the water line is warm but cold enough to hold onto, then the coil is not heating your water enough and may be coated with lime scale. The minerals will need to be cleaned out to get your water heater back in shape and heating efficiently.

If a clogged coil doesn't seem to be issue, consider what else might cause low water pressure or no hot water.

What to Do if You Have a Clogged Tankless Coil

It's probably best to call a professional to assess your water heater. It's a relatively simple process, but an expert hand will help avoid any further damage to your water heater.

NOTE: This content is for informational purposes only, and HomeX and its affiliates disclaim all liability related to it. If you decide to perform any tasks based on this information, you assume all risks, including the risk of loss or damage to property or personal injury.

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