Powermax range 155 boiler - how to set the hot water temp??

31 May 2006
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West Midlands
United Kingdom
Hi - just moved into a house with a Powermax range 155 boiler and whilst it works fine the hot water is scalding hot (dangerous for little kids etc). Is there a way to turn the water temp down? We have no manual or instructions and I can't find anything on the web to help me. Any information welcome!

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I think that I am right in saying the DHW temperature is controlled by a three port blending valve on your boiler.

This has an adjustment on the top but its more likely to be seized up inside or even the temperature sensing element may have failed.

If you are really competent you could drain it and take the unit apart and try to work out whats wrong. Or get someone to do it for you !

Tony Glazier
Tony - thanks for that - I'll have a squint at it tonight and see if I can spot the blender - much appreciated.

I'd hoped it was adjustable via the input panel, through some specific key strooke sequence - as the boiler in the old house had been. Should have guessed it would be more complicated!

the blender valve is adjustable, but not by turning the top, you have to take the cap off and twist the shaft, although they can be known to seize up ....
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Just wanted to say thank you - the advice given worked perfectly - adjusted the valve and all is now well - hot water without burnt kids. Much appreciated. Jeff.
You were lucky!

The engineers expectation is that it was set correctly and has now failed !

In your case it was never set properly in the first place!


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