Central heating reset?

DazShot · Apr 11, 2020

I have split-level heating in a 3 storey townhouse. The control unit on the ground floor is wired and controls the heating on the ground floor and half of the first floor, and the hot water. The unit on the first floor is battery powered and controls the heating for the rest of that floor and the second floor. The battery indicator was flashing on the unit on the first floor a few weeks ago, so I changed the batteries. Ever since then, or possibly even before then, something funny has happened to the second floor heating. The heating now comes on on that floor when the ground floor control unit is on for either heating or hot water.

I've dug out the manual for the ground floor unit and I can do a reset on that, but wanted to check whether that was likely to fix the issue? I'm a bit nervous about resetting in the current climate, in case I can't get anything working again!

Brambles · Apr 11, 2020

What is the make / type of both controllers please?

DazShot · Apr 11, 2020

Brambles said:
What is the make / type of both controllers please?

Ground floor is a Danfoss SystemFit TP9000 and first floor is a Myson controller, but can't see a model number.

Thanks

Brambles · Apr 12, 2020

It sounds like the zone valve for the second floor heating zone is stuck in an open or part open position.

To test this:

Turn the downstairs thermostat to it’s lowest setting. Turn the upstairs thermostat to its highest setting - 30 degrees plus. Does the boiler fire? If it fires the wireless thermostat is ok, but the xone bslve is not opening / closing properly. If not it is either the thermostat or the zone valve. However, as it is passing the zone valve would be where I would start troubleshooting.

Try to take some photos of the Myson thermostat, its receiver unit and associated zone valve and post them if you need further direction

DazShot · Apr 12, 2020

Tried the above and the heating did go on on the 2nd floor. Where would I find the receiver unit and zone valve?

king of pipes · Apr 13, 2020

Brambles advice is sound on this one first place to start is the zone valve. Kop