Unusual Cental-Heating Problem

[Bodragon]

Just moved into a new flat and have strange problem with central heating. The boiler, a Potterton Suprima 60 L, looks fairly new. Much newer than the timer control or thermostat that's for sure. There is a separate hot-water circuit that feeds an immersion tank. The problem is this: When the water is switched off at the control panel the heating works fine: the rads go hot and cold depending on the thermostat as they should. However, when the water is set to ON, the radiators don't ever go cold, they just remain warm when the thermostat clicks off. Furthermore, when the heating is switched off at the control panel the rads remain warm and will only go cold if the water is switched off too. Basically, whenever the water is on, all the radiators go warm - not hot, just warm. Would I be right in suspecting a faulty control valve which is not closing fully and is letting some hot water through to the heating circuit?

Thanks for any help

 

[Fluffster]

I believe you suspect correctly, test ithe pipes leading to and from the valve with the hot water control just on and it should indicate if it is letting by into the heating circuit.
Pete

 

[ChrisR]

Sometimes this sort of thing can be a wiring error.

Check whether the lever on the motorised valve is hooked onto the "man" position. 5p says it is because the motor's not working.

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boardragon replyed

Thanks for your comments. I've spent the morning further testing the system and this is what I've discovered - shock horror!

Both motorized valves working normally but the heating circuit comprises just the upstairs radiators. The downstairs rads appear to be tapped from the boiler-side of the valve which means whenever the boiler is on whether it's for the water, the heating, or both, the downstairs rads come on. the pipe-work looks incredibly amateurish. I'm no pro myself but a one-armed monkey could do better than this. What a nightmare! icon_sad.gif

It's fixable, what isn't? But it's gonna mean floorboards coming up, sigh...

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