Hot water not hot enough!

[btwellz]

Hi there I'm having trouble with my hot water, I'm struggling to get the hot water piping hot for a bath. I have a biasi 24s combi boiler. The c/h is great and really hot. I have tried messing with the cold water input backing that off slightly. Normally the hot water would be cold but if you backed off the hot tap so the water flow was reduced the water would come very hot after a few seconds, I cant even seem to do that now only warm water at best.

Any ideas

Ben

 

[btwellz]

Any thoughts ?

 

[chrishutt]

Probably failure of the diaphragm (or flow switch).

 

[kev25v6]

Im having this problem right now and untill the gasman comes on thursday ive found that running the hot tap on only a quarter turn and having the sink cold tap slowly running gives water hot enough for a bath.Its only a temp fix though.

 

[chrishutt]

It could also be caused by cold water by-passing through a shower valve with a defective non return valve (NRV). Do you have a shower valve? If so does turning the temp control fully to the cold position help?

 

[DP]

Let the system cool down (pipes under the boiler that feed the rads are cold to touch and boiler is cold as well). Now run a hot tap and hold aforementioned pipes to see if they get hot.

It is possible the boiler is heating radiators as well as water resulting in tepid water. If this is the case, isolate one of the pipes mentioned above and see if the hot water delivery is improved.

 

[bengasman]

When you run the hot water and keep your hand under the tap, is the temperature consistently warm or does it vary from hot to cold and back?

 

[btwellz]

Thanks for the help. when the rads are hot or the heating been on for a while I get hot water. If the system is cold like on a morning or coming in from work the hot water is cold at best warm. I'm waiting for the plumer to come and service the boiler will give him a ring as he is waiting for the service kit. I have to also but heating on to light boiler as the diapham has gone so I suppose this won't help much. Just another thought could my heater exchanger be clogged up with lime scale? or is this fine due to the rads been hot?
Ben

 

[btwellz]

Warm temp all over the place not consistant.

 

[bengasman]

Warm temp all over the place not consistant.

blocked plate exchanger

 

[btwellz]

blocked plate exchanger, is this an easy job or does it have to be done by corgi guy?

 

[zimmers]

gas supply big enough if its 15mm hell say you need 22mm from the metre to boiler really any 22mm is ok to take a tee from but if the h/water is struggling then poor gas supply is very common

 

[clf-gas]

blocked plate exchanger, is this an easy job or does it have to be done by corgi guy?

Quite easy, if you dont have the manuals you can download from here http://www.biasi.co.uk/frameset_acro.htm

 

[btwellz]

Heat exchanger looks clean! Waiting for it to cool down. Would getting the hover in there be a good idea?

 

[EliteHeat]

Heat exchanger looks clean! Waiting for it to cool down. Would getting the hover in there be a good idea?

Is that a joke? if so, good one.