Hot water only when heating is on.

[G.S.]

I have an Ariston Euro Combi Boiler SX20 MFFICE
The hot water only works when the heating is on.
I have changed the diaphragm but this has made no difference.
When I switch the micro switches manually the boiler fires up but when the hot water tap is turned on nothing happens. The pin from the diverter valve raises up as it should.

Any ideas please.

Garry

 

[Gasguru]

Do you mean the pin moves up but not sufficiently far enough to operate the switches?

I presume you did replace the cap on the end of the pin.

 

[G.S.]

The pin rises up enough.

Yes a new cap was put on.

 

[Gasguru]

Are all the microswitches being switched? - have you checked with a meter - perhaps one has high resisitance on its contacts but when you operate it manually the resistance drops.

 

[G.S.]

I'll give that a go.
I havent got a meter but I'll get one from work on Monday.

Thanks.