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 Rennai tankless water heater- hot turns to cold
Author: BrittanyO (GA)

Problem - when I turn the hot water on in the shower, if I turn a sink faucet to hot at the same time, the shower water turns cold. It’s happening in every bathroom in the house. It also turns cold if I run the dishwasher or washing machine at the same time as the shower.

The hot water will still be hot in the sink if I try to run another faucet or appliance at the same time, but the water won’t stay hot for very long.

Any idea why this is happening? The water heater is only a year old.

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 Re: Rennai tankless water heater- hot turns to cold
Author: steve (CA)

Edit- The post title didn't "sink" in.

Edited 1 times.

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 Re: Rennai tankless water heater- hot turns to cold
Author: packy (MA)

hey steve.. is the CA heat getting to you? hahaha

anyway. for the TANKLESS heater the first thing to do is flush the coil.


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 Re: Rennai tankless water heater- hot turns to cold
Author: steve (CA)

Not much heat in San Francisco and northern peninsula. 55* right now, expected high of 62* today. Saturday is forecasted to be the hot day of the upcoming week at 70*.

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