Hot water but no central heating



My father has a problem with his heating. Basically, his hot water is working but the heating isn't. He has a Potterton Suprima 40 Boiler and a Potterton EP2002 programmer unit, both located in the kitchen. The whole installation is about 4 years old.

When the heating is switched to 'always on' and the room thermostat is turned up high, the boiler lights and stays on for a couple of minutes or so, then turns off. The 5 radiators downstairs are stone cold, and the 3 radiators upstairs they are just warm (this may be because thay are being warmed by the hot water).

The pump does not appear to be switching on at all (I cannot hear or feel it whirring). However I do not think the pump is broken because I connected it directly to the mains electricity supply (via a wall socket) and it works fine (I heard and felt it whirring). Does anybody know which component controls the pump? Is it the main programmer unit? (The programmer appears to be working fine in all other respects). Or is there some kind of electronic controller in the boiler unit which tells the pump when to switch on? There is a motorised valve near the pump which says 'auto' and 'mid' on it. It is set to auto. Could this be at fault?

Any advice would be very much appreciated.
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I am not a plumber or heating engineer.
I had this problem once before, it is on these forums (can't remember where) I thought my pump was fine as it, like yours whired away quite merily, i called in someone and within 10 seconds he said "pump has gone" I changed it, problem solved. The person for whom i mentioned it on these forums also changed his pump and that solved his problem too. Some one then posted that the pumps do not last that long.

But one other thing (cheaper option) try moving the valve first it MAY be that.

a new pump is less than £40

for a pump try


Staff member
17 Aug 2001
Reaction score
United Kingdom
Hi andrewjo1,

You have registered with an invalid email address. Either login and correct it or send me an email at If if is not corrected within 24 hours I'll delete your message. This topic will remain locked until your email is corrected or until I delete it tomorrow :evil:

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