franklymdear

Hello boiler experts. We recently extended out heating system, and have adjusted our Baxi 100/2 HE Plus boiler to cope with the added heat load. This has been done in accordance with the manbufacturers guidance, simply by removing the red jumper on the pcb. However, when the thermostat or timer shuts it down we get boiling on the heat exchanger and bangs in the pipes. Seems to me it needs a pump overrun, but this is not required according to the manual, and as the boiler does not use a permanent live, cannot be simply achieved. Any one else had this problem and solved it?

Thanks

Frankly