I have a 418 and have had issues with cycling once it reaches target temperature. The problem seems to be the boiler cannot modulate down enough and eventually cuts out. This is fine but the problem is the boiler try’s to restart when the inlet temp is 20c below target temperature, 20c is not enough and the high power start up causes it to cut out. My solution to reduce this is to de-rate the boiler as low as possible so it reaches the target temperature later meaning it takes a long time before it would cut out and normally heats the house ok. Also set minimum target temperature to 60c any lower and it will defiantly cut out early. My temperature difference between inlet and outlet is about 15c I am always looking for a way to get this closer to 20c. I also run the pump slow to get the best temperature drop, running it high can help with the restarts but the drop will be low.
Gaz
Gaz
