Author Topic: temperature control on hot water  (Read 2319 times)

Craig

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temperature control on hot water
« on: January 09 2021, 00:30 »
I've just had a query from another Bavaria owner who seems to be struggling to find a solution to a problem that I  have as well. This problem has occurred from new.

The hot water coming out of the taps is extremely hot, to the stage of being dangerous. There appears to be a tempering valve next to the water heater but no matter which way it is turned it does not appear to control the mixing of hot and cold water at the tank.

Is there an easy fix to this? I don't want to pull the pipes off without knowing what I am going to do.

Craig
" Shirley Valentine"
Gold Coast
Australia

Yngmar

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Re: temperature control on hot water
« Reply #1 on: January 09 2021, 10:24 »
If there is a mixing valve, it may just be stuck.

Our boat didn't have one and the 90°C hot water would damage the plastic fittings on the hot water plumbing, which are only rated for a much lower temperature (60 or 65 - forgot).

I've fitted a thermostatic mixing valve (from a solar water heating system - cost about €20) at the calorifier outlet, which solves the problem with the pipe fittings and also prevents scalding.
(formerly) Sailing Songbird  ⛵️ Bavaria 40 Ocean (2001)

tiger79

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Re: temperature control on hot water
« Reply #2 on: January 09 2021, 10:53 »
Yes, a thermostatic mixing valve is the answer.  You may have one already, or you may have been adjusting the pressure relief valve.

This diagram shows how to plumb a thermostatic mixing valve properly - https://www.surejust.co.uk/images/uploaded/documents/Surecal%20Horizontal%20Calorifier%20Connection%20Instructions.pdf

Craig

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Re: temperature control on hot water
« Reply #3 on: January 10 2021, 09:00 »
I do have a tempering valve ( mixing valve) and you may be right. It may be stuck.

Has anyone serviced this, or is it merely a pull out and replace item?

Craig
"Shirley Valentine"
Gold Coast
Australia

tiger79

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Re: temperature control on hot water
« Reply #4 on: January 10 2021, 11:10 »
It's a cheapish replacement from a plumbers merchant.