Changed thermostat and no heat down stairs

[Square271]

I have swopped a thermostat today as the room stat was not sending power to it. So changed both items. Now when i put heat on the radiators are red hot upstairs but nothing down stairs. There is power at the stat and the pump but will not heat down stairs. Could this be a wiring fault or a plumbing issue? Thanks

 

[EFLImpudence]

Are you saying there are two thermostats?

 

[ban-all-sheds]

I have swopped a thermostat today as the room stat was not sending power to it.

How do you know?

And should it have been "sending power to it"?

So changed both items.

Which "both"?

Now when i put heat on the radiators are red hot upstairs but nothing down stairs. There is power at the stat and the pump but will not heat down stairs.

Have you checked that the zone valve(s) are working?

Could this be a wiring fault or a plumbing issue? Thanks

As it's the wiring you've fiddled with, probably the former.

Unless you misdiagnosed the problem originally.

 

[Square271]

Try and make it clearer. The main panel was not calling the thermostat and was not working. So I swopped the main panel an lp112 and the mechanical timer direct swop. Now the main heating control is calling the thermostat and heat is working upstairs but nothing downstairs.

 

[PrenticeBoyofDerry]

Has your central heating been off for a while?
Try turning the working radiators off at the rad valves and see if any hot water is then pushed around the cold rads. Can we assume that you do not have zoned heating for upstairs/downstairs?