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I have a tankless water heater and it is not warming the…

I have a tankless...

I have a tankless water heater and it is not warming the water and coming up with a C7 error. I have turned it on and off a couple of times and it will warm the water for a little and then goes off again. What do I do?

Contractor's Assistant: How old is the appliance? Have you gotten error messages before?

It is at least 8-10 years old I think. Was in the house when I bought it. Never have had this message before.

Contractor's Assistant: Do you plan on doing the work yourself?

Depends how easy it will be

Contractor's Assistant: Anything else we should know to help you best?

I don't think so

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Answered in 8 minutes by:
10/7/2017
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 9,707
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified

Hello, I need the brand and model number of the water heater.

.

I also need to know when it was last flushed with a mild acid or white vinegar.

.

So far it sounds like it is tripping its high temperature safety cut off switch due to low water flow and a clogged up heat exchanger.

.

If you tell me which direction you are from the center of the nearest town or city I will see if I can find a well rated service outfit for you.

We can go from there

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Customer reply replied 9 months ago
It is actually a Paloma USC1-117. I have never flushed it. I am in Scarborough, Ontario.
Customer reply replied 9 months ago
Canada

click here please, this outfit has very high ratings on a high volume of work, get and estimate from them to acid flush your water heater as a first step, then go from there with another estimate for repairs if needed.

Stay in touch as needed.

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When you have what you need, its time to select the "Finish and rate your expert" near the top of your page and click on it to close the question. Thanks.

Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 9,707
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified
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