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I have a ZWB-3A combi boiler unit that heats a warm floor…

Customer Question
I have a ZWB-3A...

I have a ZWB-3A combi boiler unit that heats a warm floor system as well as domestic hot water. The domestic hot water fluctuates between warm, hot, and cool temps. I've tried purging periodically, but that doesn't work all the time. Can you help?

Contractor's Assistant: Have you talked to a construction professional about the floor?

What about the floor?

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

Well, yes, if not too technical..

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

Not that I know of.

Submitted: 4 months ago.Category: HVAC
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Answered in 2 hours by:
12/17/2017
HVAC Technician: Phil, Mechanical Engineer replied 4 months ago
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 9,316
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified

Hello, when domestic hot water fluctuates like that is usually due to insufficient water flow through the water heater..... open the bathroom sink hot water tap as you are running the shower, if that 'fixes' it then the shower water flow is too low to keep the water heater on.

That is test number one.

We can continue after that test without any time limits

My goal is to give you the best experience possible! I hope I have earned a 5 star rating! Please remember to rate my service by selecting the 5 stars at the top of the screen before you leave today. If you need more assistance, please use the reply box and let me know.

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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 9,316
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Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial

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