Daren't Stop Running

[Digimon]

Hi, I have a (1992) Vaillant Combi boiler VCW GB221H. Last month it failed (both hot water & heating). No apparent relay / pump action.

Recently I have found that if I vigorously turn / agitate the impeller (it's not particularly free-running - should it be?) on the pump before switching the heating on, I can eventually get the boiler to start, and it works as normal (heating & HW), but once the pump switches off, it won't restart. It takes me ages to get it going again. Once going, it runs without any apparent labouring.

I have resorted to setting the room thermostat to max (to ensure the pump is always on) and regulate the boiler temperature using the control dial on the boiler. I've had it running continuously (albeit, not very efficiently) for 2 weeks.

Any ideas? If the pump is knackered, surely it would never run

 

[chrishutt]

The pump is knackered. And a replacement will cost best part of £100. But in the meantime you can set the pump to run continuously by changing the pump selector link at the extreme left side of the terminal box. the boiler manual will tell you which of the three settings is for constant pump. At least you can then use the room stat to control boiler firing.

 

[Digimon]

Thanks Chris. I'll be getting a plumber around to change the pump, since I don't want to mess the boiler up this time of year! I wasn't given a boiler manual when I bought the house, but will take a look for the jumpers.