C Heating ok, Hot water NOT, in a combi

[Stew160]

HELP...............

Running a Ideal Response 120000 BTU boiler, has been running fine for years, but now, heating working fine, but no hot water! taps run freely but only cold water.... HELP!
I am thinking it can't be anything major with heating working fine, but looking for any help before I call an engineer out to look at it. I'm not a plumber or anything, but am very good at DIY so looking for a DIY fix if poss.

 

[Stew160]

HELP...............

Running a Ideal Response 120000 BTU boiler, has been running fine for years, but now, heating working fine, but no hot water! taps run freely but only cold water.... HELP!
I am thinking it can't be anything major with heating working fine, but looking for any help before I call an engineer out to look at it. I'm not a plumber or anything, but am very good at DIY so looking for a DIY fix if poss.

Come on guys............give me a clue!!! anything major????

 

[doitall]

Perhaps they're waiting for information, like where the hot water comes from and what controls you have.

Then again they may have all gone to bed

 

[Stew160]

thanks for that, , heating is controlled by a room thermo, and thermostatic valvues on most rads, hot water "should" be on demand, like i said, has always worked fine, nothing new, nothing changed so nothing obvious to explain why its not working now.

Water runs warm when heating has been on, but no direct heating of water at all.

 

[BDL]

More than likely the flow switch has stuck or the dhw thermister is defective. Neither job expensive or too difficult to rectify.

No diverter valves or such to be concerned about.

 

[Mikeyboy]

I would suspect a faulty water flow switch , or , possible fault on the diverter valve .

 

[Stew160]

Thanks guys, anything I can do to try and rectify or is it a case of calling out a pro??

 

[ChrisR]

It doesn't have a diverter valve.
Trivially simple to diagnose if you have a multimeter and the manual though.
Does the red HW light come on, for a start!!

First flow switch I changed took 5 minutes, the last one about an hour, access is difficult! Having taken the last one I took out apart, I can't find anything wrong with it, but the new one cured the problem.

Meanwhile, put the ch on and you'll get some HW.