M
markjsmith2000
Baxi 105e Instant fires up and pre-heats the water OK (no hot water demand at this point). When a hot tap is turned on, the DHW flow switch is activated, the DHW light comes on, the fan runs, but the boiler doesn't always fire. I thought this might be a problem with the fan pressure switch, but if this was the case I don't think the boiler would fire up to pre-heat the water would it? Could it be a PCB problem or something else? I've heard a microswitch 'latching' like it can't quite switch on properly, but I'm not sure which one this might be.