any advice please RE: Potterton Netaheat electronic

[spekky]

hi woke up this morning to a freezing house!!!

right the boiler is a potterton netaheat electronic, with an potterton EP3000 programmer and honeywell room thermostat, now with both hot water and central heating set to on 24hrs on the programmer, the boiler does not come on when the room thermostat is set to a higher temp normally set it to 22c flick it up to 25 hear a small click within mins the boiler kicks in!, you still hear the click from thermostat but boiler does not kick in??? however if a the hot tap is run for a small amout of time the boiler will then kick in to heat the hotwater so fault would appear to be on the central heating side! is there anything i can try? i am no expert but what are the chances of room thermostats just failing? or does it sound like the programmer, By the way when the boiler does come on for the hot water the radiators do start to warm up but the second the tank obviously hits temperature the boiler cuts out and will not stay on for the central heating!

any advise would be much appreciated

thanks[/b]

 

[bathjobby]

Sounds like your 3 way valve could be stuck in mid position, would explain why rads also start to heat up when water stat fires boiler. would also explain why CH does not fire boiler, for CH the 3 way valve motor powers valve to CH position at which point a micro switch contact is made which signals to the boiler that the valve position is good. If your valve is stuck mid way, boiler won't be getting this signal either.. Could try gently tapping it with hammer handle to see if it frees it, but there again, how old is it, are you in hard water are, have you treated your system, etc, etc, it may need replacing ...

 

[spekky]

thanks for the reply!

the system is i would guess as old as the house 17years old, dont know about treatment i have only been in 3 months but there is no instructions for the boiler or anything!!!

water is hard, i am in northampton

where do i find this valve

bottom or top?

cheers

 

[bathjobby]

Find your pump (airing cupboard normally) and it is probably mounted on the top of the pump. Pipe comes out of pump into valve (which is turned by motor housed in square aluminium box sitting on top of valve) and then the pipe 'T's off, one way into hot water cylinder and other way in CH pipes.