Powermax no/tepid hot water

[John Cotton]

I have a Powermax (thermal store) boiler. When the central heating and hot water is on there is hardly any hot water at all - and when only the hot water is on there is some but its tepid at best. ANY IDEAS ????

 

[sonray ltd]

is the pump running ?

 

[John Cotton]

Yes and central heating works fine.

 

[sonray ltd]

has this happened over a period of time ?

 

[John Cotton]

No , happened all of a sudden. Hot water comes through taps for a few seconds, then goes tepid / cold.

 

[sonray ltd]

what model is it ?
has it got a fault display code ?

 

[John Cotton]

Its a Powermax 135 - no faulty display code.

 

[sonray ltd]

does the boiler run ok in just hw mode ?
is the pipes feeding the coil hot ?
has it got a blending valve fitted ?