Grundfos pump problem

[sw197]

[h=2][/h]

I wonder if anyone can help. I have henco underfloor heating running from a Worcester bosch gas condensing boiler greenstar 15i. The boiler has three two way zone valves, one for central heating radiators, one for hot water, one for underfloor heating. The water and radiators have there own programmer. The radiators have a dedicated thermostat. The underfloor heating has its own brass manifold, own pump grundfos ups2 ph 50/60, it's own programmer and its own thermostat. When I switch my water or my radiators on the underfloor heating pump switches on even though the underfloor heating controller and thermostat is off. The underfloor heating doesn't switch on its just the pump running. If I switch the underfloor heating on at the controller and thermostat it heats up fine. My question is why is the underfloor heating pump coming on with water and radiators - doesn't the boiler have a pump running these. Why would I want my underfloor heating pump running for what seems a needless reason? Also the thermostat on the manifold for underfloor heating is down at 40 degrees - should this be higher? Any help appreciated.​

 

[PhoenixServices]

Don't touch the thermostat on the uf heating it should of been set up correctly by the installer. Sounds like an electrical fault. Best to get a heating engineer who is good with electrics or an electrician who is good with heating.

 

[rpm]

Any electrical or plumbing work recently been done?

 

[sw197]

Hi
two of the motorised valves were changed (hot water and ufh) on boiler as they had failed. The head was replaced of pump. So pump is brand new. Not sure if wiring new valves can cause problem - work was done by a plumber, but I'd like to know in my own mind what's going on as well as getting mixed messages! Thanks.

 

[sw197]

Hi
two motorised valves were changed (hot water and ufh) on boiler as they had failed. The head was replaced of pump. So pump is brand new. Not sure if wiring new valves can cause problem - work was done by a plumber, but I'd like to know in my own mind what's going on as well as getting mixed messages! Thanks.

 

[josh]

Sounds like you have got a back feed on the electrics which is why pump comes on when it shouldn't, defiantly a job for a pro as can open up a can of worms here.