I am having problems with my vaillant 937 ecotec boiler, approx 7 years old
It will not give any hot water or heating and comes up with error code f.75 which says is the pressure sensor switch or pump.
I can hear a low rumble noise from the pump also clicking as if to work and have changed the pressure sensor switch for a new one, but still not working
.
Have googled to see what else it could be. Someone has mentioned about the expansion vessel, I have deflated the vessel which blew out air fast at first then little dribble of water came out. when re pressurising the vessel at 1 bar the boiler will fire up but the temperature will shoot over 100 degrees and the pressure gauge rapidly goes up to 3 bar and shuts boiler down, not all the time though, i can also get it to fire up like this by opening the filler loop to 2 bar, then does same again with temperature and pressure.
Any help appreciated
It will not give any hot water or heating and comes up with error code f.75 which says is the pressure sensor switch or pump.
I can hear a low rumble noise from the pump also clicking as if to work and have changed the pressure sensor switch for a new one, but still not working
Have googled to see what else it could be. Someone has mentioned about the expansion vessel, I have deflated the vessel which blew out air fast at first then little dribble of water came out. when re pressurising the vessel at 1 bar the boiler will fire up but the temperature will shoot over 100 degrees and the pressure gauge rapidly goes up to 3 bar and shuts boiler down, not all the time though, i can also get it to fire up like this by opening the filler loop to 2 bar, then does same again with temperature and pressure.
Any help appreciated
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