Worcester Comfort+II losing RF connection

[ashiery]

I've a Worcester Comfort+II thermostat which connects to the Greenstar boiler via a "Key" receiver unit inserted into a slot in the boiler

The system is three years old, and has been completely fine, but has in the past few days started losing the RF connection

Following instructions from the user guide and online searches, I've:
- replaced the batteries in the thermostat with new ones
- removed the batteries from the thermostat, waited 10 minutes, and re-inserted them
- factory reset the thermostat
- factory reset the key
- moved the thermostat to within 20cm of the key, with a direct line of sight
- unpaired and re-paired the thermostat and key from the installer menu on the thermostat

Each time, it seems to work fine, the LED on the key goes from flashing yellow (pairing) to solid green (paired) and the controls on the thermostat can then be used to switch the functions of the boiler on and off correctly

But, then, a few hours later, the connection is lost, and the message ("No RF signal") appears on the thermostat again

Anyone have any idea what's wrong?

 

[CountryFan]

Out of curiosity, what batteries are you using, Zinc or good quality Alkaline?

 

[accelerator]

Radio interference from something?

 

[ashiery]

I'm using good quality alkaline

RF interference: possibly. There's no pattern with anything I'm using, but we live in a flat so could be the neighbours, not sure what I could do about it?

 

[accelerator]

Try moving the thermostat nearer to the boiler and see if that makes any difference?

 

[accelerator]

I would just do the obligatory Copilot AI search, go to:

Microsoft Copilot: Your AI companion

Microsoft Copilot is your companion to inform, entertain and inspire. Get advice, feedback and straightforward answers. Try Copilot now.

copilot.microsoft.com

and paste in:

"Why is my Worcester Comfort+II thermostat losing connection after a few hours, and the message ("No RF signal") appearing?"

and check you've done what it says there, which I think you have.

If moving the thermostat nearer doesn't do anything, it's going to be a hard problem to troubleshoot, and may be a faulty RF module, so I would talk to Worcester support.