Boiler firing up - no demand from HR92's
Posted: Sun Oct 18, 2020 1:24 pm
Hello All,
I will be very grateful if someone could advise where to find a root cause of my problem.
I have Evohome system installed in late 2017 (ATC928G3000, 9x HR92's & HW Kit). So far it has been running excellent, with some minor connectivity issues until recent.
Almost every day, at random times, boiler & pump are running even that there is no demand from any of the TRV's and BDR91 lights are not illuminated. I have narrowed my problem to BDR91 that controls heating. I have completed several tests so far:
T1: During the above event, I have pressed the manual start button on the BDR91 and left it running for approx. a minute. Then I have pressed it again, light goes off, boiler & pump stops and starts again within less than 30 seconds. No demand from HR92's
T2: During the above event, I have switched off central heating with main switch button. Left it switched off for few minutes, switched it back on again, boiler & pump started without the demand from HR92's
T3: During the above event, I have raised a demand temp in one of the rooms, left it running for approx. 15 minutes, and reduced the temp. Boiler & pump has restarted within few minutes without the demand from the HR92's
T4: During the above event, I have disconnected the BDR91, by taking the face plate off. Boiler & pump has stopped. Re-connected the face plate to the BDR91, boiler & pump DID NOT restart.
Please advise if wiring is wrong (was working ok for last 3 years) or BDR91 needs replacing or something else I should look at.
I will be grateful for support and advices.
Kris
I will be very grateful if someone could advise where to find a root cause of my problem.
I have Evohome system installed in late 2017 (ATC928G3000, 9x HR92's & HW Kit). So far it has been running excellent, with some minor connectivity issues until recent.
Almost every day, at random times, boiler & pump are running even that there is no demand from any of the TRV's and BDR91 lights are not illuminated. I have narrowed my problem to BDR91 that controls heating. I have completed several tests so far:
T1: During the above event, I have pressed the manual start button on the BDR91 and left it running for approx. a minute. Then I have pressed it again, light goes off, boiler & pump stops and starts again within less than 30 seconds. No demand from HR92's
T2: During the above event, I have switched off central heating with main switch button. Left it switched off for few minutes, switched it back on again, boiler & pump started without the demand from HR92's
T3: During the above event, I have raised a demand temp in one of the rooms, left it running for approx. 15 minutes, and reduced the temp. Boiler & pump has restarted within few minutes without the demand from the HR92's
T4: During the above event, I have disconnected the BDR91, by taking the face plate off. Boiler & pump has stopped. Re-connected the face plate to the BDR91, boiler & pump DID NOT restart.
Please advise if wiring is wrong (was working ok for last 3 years) or BDR91 needs replacing or something else I should look at.
I will be grateful for support and advices.
Kris