A21 fault on Worcester boiler

[Georgemidnight]

My boiler is still working fine and my new Hive thermostat works manually (just not on the app).

The boiler regardless of what’s happening still shows the A21 fault which I believe is an RF signal fault? Any ideas?

 

[OnlQQker]

Batteries perhaps?

A21 Worcester Boiler Fault Code and Thermostat A21 Error Codes

Worcester Boiler A21 Fault: Troubleshoot your Worcester boiler A21 fault with our comprehensive guide. Avoid costly repairs and fix the issue yourself.

www.boilercentral.com

 

[Georgemidnight]

Batteries perhaps?

A21 Worcester Boiler Fault Code and Thermostat A21 Error Codes

Worcester Boiler A21 Fault: Troubleshoot your Worcester boiler A21 fault with our comprehensive guide. Avoid costly repairs and fix the issue yourself.

www.boilercentral.com

The hive thermostat is working fine and calling the boiler for heat. I just can’t get the Hive to work through the app, which I’m guessing is to do with the A21 (RF signal Fault)

 

[davesparks]

A21 will almost certainly relate to a built-in Worcester bosch wireless thermostat and not the Hive unit.

I suspect the boiler had a Worcester bosch thermostat originally which has now been replaced by a Hive thermostat. If the original thermostat receiver wasn't fully removed from the boiler it will still be looking for that thermostat connection and throwing up the error as it is missing.

 

[Georgemidnight]

A21 will almost certainly relate to a built-in Worcester bosch wireless thermostat and not the Hive unit.

I suspect the boiler had a Worcester bosch thermostat originally which has now been replaced by a Hive thermostat. If the original thermostat receiver wasn't fully removed from the boiler it will still be looking for that thermostat connection and throwing up the error as it is missing.

Hi Dave. Yes I threw the Worcester thermostat, how would I ‘fully’ remove from boiler?

 

[davesparks]

Hi Dave. Yes I threw the Worcester thermostat, how would I ‘fully’ remove from boiler?

That'll be why it's throwing up the fault code then!

You would need to remove the receiver from the boiler, depending on exactly which model of boiler you will likely need to re-fit the blanking plate in its place.

Obviously you should only do this if you are competent to open up the boiler and put it back together correctly.

 

[Georgemidnight]

That'll be why it's throwing up the fault code then!

You would need to remove the receiver from the boiler, depending on exactly which model of boiler you will likely need to re-fit the blanking plate in its place.

Obviously you should only do this if you are competent to open up the boiler and put it back together correctly.

It is a Worcester Comfort RF I believe. I’d be happy to do so, what will I need to disconnect?

 

[davesparks]

It is a Worcester Comfort RF I believe. I’d be happy to do so, what will I need to disconnect?

It's not a question of being happy to do it, it is about being competent, gas appliances are covered by strict rules.

 

[Georgemidnight]

It's not a question of being happy to do it, it is about being competent, gas appliances are covered by strict rules.

Hi Dave, yes I’m happy and competent to do this. I have successfully removed the boiler stat, is there some sort of ‘blank’ I can use to cover?

I have attached a photo to help