Potterton Combi 80 - Heating issue

[pwdiy]

Hi

We have a Potterton Combi 80 boiler and we have noticed that there are times when boiler runs for a minute or two on CH and stops. It would wait itself for a few minutes and run again for a minute or so and stop. This cycle repeats itself. However, this happens only sometimes. Usually when the boiler kicks in first thing in the morning, it works fine.

There are no issues with the HW supply.

Any idea what may be the issue.

Thanks in advance

 

[pwdiy]

All

Just an update. I have monitored the duration the boiler runs before it stops - it runs for about 3mins and 20seconds before it stops. I have noticed this for about 5-6 times now.

Cheers