My Vaillant boiler is showing an F75 fault.
I have worked around it so far by topping up water (I bleed radiators when they are cold in the evening to do that) in the system on chimney sweep mode; this creates a small change in pressure to get ignition ( I assume) ; then CH works for few hours till it stops (because there is no demand for H); when there is demand for H from the wireless thermometer; there is no guaranty of boiler ignition and the boiler throws an F75 again.
Another trick is to open bathroom taps but this usually takes longer to get ignition.
I also use comf mode for hot water; I get the CH to work then (if there is demand for CH) by simply opening the taps (this is the best solution so far ).
All of that suggests a sensor problem I suppose.
I tried the P00, P02, P01 and P06 programs after successful ignition but the F75 faults is not resolved. The boiler also works within the suggested min and max pressure levels. I have been using it for 2 years and 6 months (two years warranty is gone I'm afraid)
Can I ask what do you think please?
I have worked around it so far by topping up water (I bleed radiators when they are cold in the evening to do that) in the system on chimney sweep mode; this creates a small change in pressure to get ignition ( I assume) ; then CH works for few hours till it stops (because there is no demand for H); when there is demand for H from the wireless thermometer; there is no guaranty of boiler ignition and the boiler throws an F75 again.
Another trick is to open bathroom taps but this usually takes longer to get ignition.
I also use comf mode for hot water; I get the CH to work then (if there is demand for CH) by simply opening the taps (this is the best solution so far ).
All of that suggests a sensor problem I suppose.
I tried the P00, P02, P01 and P06 programs after successful ignition but the F75 faults is not resolved. The boiler also works within the suggested min and max pressure levels. I have been using it for 2 years and 6 months (two years warranty is gone I'm afraid)
Can I ask what do you think please?