Ravenheat CSI 85AT Anti-cycling

[Pete20]

My Boiler will switch on and off during CH mode with a cycle of about 30 seconds off followed by 10-15 seconds on this after a continuous cycle to reach temperature. The manual states that the Control Board is fitted with an anti-cycling device which should prevent the boiler re-starting for 2 1/2 minutes once temperature has been reached. This is clearly not working. I have been told to change the thermistors but I have checked these and they seem ok i.e around 2.5k when switching the boiler off.
Is this problem caused by a faulty PCB or any other components. I have seen this raised elsewhere in this forum but without any helpful response.
Thanks Pete20

 

[gas4you]

If everything checks out ok and you still have the fault, it could be the fan modulating board.

They have a common fault such as you describe. Could be worth a call to Ravenheat tech.

 

[Pete20]

If everything checks out ok and you still have the fault, it could be the fan modulating board.

They have a common fault such as you describe. Could be worth a call to Ravenheat tech.

When you say the fan modulating board is this the Ignition Board? The fan does not appear to cause any problems.

 

[gas4you]

The fan does not cause the problem, the problem could be the board controlling it. If it works ok for HW, then shows this fault when the heating tries to come back on, it sounds like the fault.

 

[ex Teacher]

I have the exact same problem with my ravenheat boiler that was recently fitted. I called out a boiler service specialist and he contacted the ravenheat technical helpline. He was told - or so he told me - that the boiler is meant to be working this way.
I told him about the manual saying that there's an anti short cycling device and he still maintains that the boiler is meant to be working on short cycle.
I'm still unconvinced, so please let me know if you find the solution.