Vaillant boiler error code F75 urgent help needed

[rangers]

hi, my boiler has stopped working ,error code f75 ,i have a young family with no hot water to bath my 6 month old can someone help please

[paul44]

Hi,

which model is it as the codes can vary, have listed the general one below hope it helps, recommend you get an engineer to diagnose though:-

F.75 - No pressure rise was detected on turning on the pump

Water pressure sensor or/and pump defective
Air in the heating system, quick bleeder defective
Too little water in appliance; check adjustable by-pass; connect
external expension vessel to return

[emilyb]

F75 is the pcb not acknowledging the pumping kicking in from the sensor measuring the change in pressure. Likely the sensor, also worth checking is the pump and water pressure in the system. Most likely cured by changing the sensor.

You would need to advise an engineer of the model number of your boiler to obtain the correct parts for example an Ecotec pro 28 or similar.


Emily Burton
Accolade Building Care

[stoker122]

Vaillant water pressure sensors are susceptible to a blockage of sludge and debris in the system.
It may be possible to clean the sensor, it depends on the age of the boiler and again, which model you have.
Your engineer will be able to advise the best course of action.

Regards
Jared Hooper

[rangers]

thanks for the replies ,its an eco tec pro 28 ,we've got a guy coming out later today to take a look so fingers crossed its not too expensive ,if it is a sensor any ideas how much i can expect to pay?

[syheating]

Sensor not too expensive around £25 I think. He will have to drain boiler down, but are easy to fit.

Keith

[safeflameuk]

Don't forget the labour charges! ;-)

Sensor not too expensive around £25 I think. He will have to drain boiler down, but are easy to fit.

Keith

[staffs]

I have found several whereby the metal gauze filyer in the pipe where the pressure sensor fits gets partially blocked with muck. This can be seen when the sensor is removed. May get away with cleaning both but often sensor reqs replacing also.
Vaillant appear to recognise this as a known fault and now produce an F75 repair kit which includes 2 pipes that replace the hose connected pipes and a new sensor which now fits into new position and wiring harness kit .

[safeflameuk]

Think you hit the nail on the head there staffs

I have found several whereby the metal gauze filyer in the pipe where the pressure sensor fits gets partially blocked with muck. This can be seen when the sensor is removed. May get away with cleaning both but often sensor reqs replacing also.
Vaillant appear to recognise this as a known fault and now produce an F75 repair kit which includes 2 pipes that replace the hose connected pipes and a new sensor which now fits into new position and wiring harness kit .

[AlanTownend]

Hi Rangers,

It looks like the F75 is normally associated with the pressure sensor (part no. 0020059717). You should be able to pick one of these up for around £16 +VAT.

Alan T