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Jun 30, 2017
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Bury
Member Type
DIY or Homeowner
I've been having an issue since Wednesday where my hot water from the showers in particular (I have 2), are lukewarm at best. The "flow" seems to be absolutely fine and has always been strong.

The main bathroom shower is a bog-standard mixer tap with a shower hose. The en-suite shower is thermostatic.

The bathroom mixer taps and kitchen mixer taps are piping hot (I have to move my hand away from them quickly when the hot water tap is fully opened) and my combi boiler (24Kw, coming up to 6 months old) seems to be working as it should as the boiler is definitely running with the hot water on.

I got the impression that the boiler was struggling to keep pace and was not heating the water fast enough so I experimented by closing the stopcock ever so slightly. As if by magic, piping hot showers again, albeit at a noticeably reduced flow.

Is this sort of thing normal at this time of the year? My logic says that mains water coming in from outside would be much cooler at this time of the year and therefore the boiler would have to work doubly harder to keep the water warm when it is flowing through?

Or could this be a more serious issue?

Thanks,

Jamie
 
I've been having an issue since Wednesday where my hot water from the showers in particular (I have 2), are lukewarm at best. The "flow" seems to be absolutely fine and has always been strong.

The main bathroom shower is a bog-standard mixer tap with a shower hose. The en-suite shower is thermostatic.

The bathroom mixer taps and kitchen mixer taps are piping hot (I have to move my hand away from them quickly when the hot water tap is fully opened) and my combi boiler (24Kw, coming up to 6 months old) seems to be working as it should as the boiler is definitely running with the hot water on.

I got the impression that the boiler was struggling to keep pace and was not heating the water fast enough so I experimented by closing the stopcock ever so slightly. As if by magic, piping hot showers again, albeit at a noticeably reduced flow.

Is this sort of thing normal at this time of the year? My logic says that mains water coming in from outside would be much cooler at this time of the year and therefore the boiler would have to work doubly harder to keep the water warm when it is flowing through?

Or could this be a more serious issue?

Thanks,

Jamie

One of the major problems with combi boilers is Temperature Rise, so if the incoming is colder then the water coming out of the hot taps will be colder too.

Its not like a tank of hot water where you can set the temperature to 60c, a combi will only raise the figure of the incoming main. You can adjust the temp on the boiler but that will use more gas.

Pretty poor really and is the reason you should select a combi that has the best hot water specs......everyone talks about kwatts but there is a lot more to it..

Personally I think combi boiler installations should be limited to flats. They use too much gas and leave the user completely reliant on the boiler for hot water. They break down all the time leaving some poor sod in the middle of winter with no hot water or heating.
 
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