Drayton Wiser Thermostat or boiler issue - Heating is not turning on

Hi,

I had a Drayton Wiser 3 channel thermostat installed in June, 5 months ago. It was tested on the day of install and all good. I started using it in September once it started to get cold and all was working fine for the past 2 months until the last few days.

House has a dual zone setup so I have a downstairs thermostat which is on Channel 1 and an upstairs thermostat which is on Channel 3.

If I turn the heating on via the upstairs thermostat, the heating comes on fine. But when I turn it on downstairs, the thermostat and app show heating on but the radiators do not warm up.

The ideal combo boiler also shows 00 which means there’s no demand for heat.

I switched my downstairs thermostat to channel 3 just to rule out an issue with the thermostat and it turned the heating on upstairs. So the thermostat definitely works. I also changed the batteries and reset it.

So it seems like the issue is with Channel 1 but what does that mean? Is that an issue with the boiler or a valve or? I haven’t got a clue and not sure if I need to get a gas engineer out to fix it or if it’s maybe a simple fix somehow? Any help would be much appreciated.

No issue with the boiler I don’t think as hot water works fine and heating upstairs works fine. But nothing happens when I turn the downstairs one on. Sometimes it comes on but not for long then just turns off. So don’t know if it’s just not reading the temperature correctly. I did turn it up from the usual 22°c to 25°c and it still wasn’t on for long. Baffled as to what is making it come on sometimes (although not for long) and what is making it not come on at all in most cases.

It’s getting really cold now and the downstairs one is the only one that gets used since heat rises so never had the need to really turn the upstairs one on. So it’s annoying that the downstairs one has stopped working.

UPDATE: it was the valve head, got it replaced for £65 (part was from Amazon for £25 + labour was £40. Took 20 mins for him to sort it). Working perfectly now 🔥 👌🏽