vaillant ecotec pro28

[alexmurchison]

a recent callout regarding the above boiler with the following complaint. keeps tripping out every 2 days or so. fault code F75. owner said pressure seems to drop so she had been filling via the filling loop then re setting. then again 2 days later would do the same. 1st problem i noticed was that a radiator with severe rusting was dripping badly and so i replaced along with a scetion of pipe, thus eliminating the pressure dropping throught the leak, so i thought. I also checked pump / auto bleed / PRV and pressure vessel charge, all seemed ok. i re pressurised the system to around 2 bar before switching on, it worked fine and held pressure, then today was called to say it had cut out again with fault code F7 5, no pressure drop detected

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! what would be the next part to check as another post mentioned pressure valves / sensor ?

 

[SimonJohns]

Post it in the non public gar forum. You'll get an answer straight away then

 

[dancinplumba]

He carnt tho

 

[mattyp]

Clean out the water pressure sensor and the little hole it sits in, prone to buildng up with crap ! If that fails poss replace the sensor or fit a f75 kit from vailiant.

 

[alexmurchison]

Clean out the water pressure sensor and the little hole it sits in, prone to buildng up with crap ! If that fails poss replace the sensor or fit a f75 kit from vailiant.

thanks, been reading a few other posts and all seem to point to this sensor. im sure i can pick one up to be on the safe side as it normally trips every other day on first start up in the morning. so having to drain the system to clean it to then have to do it again to poss replace is all adding up in labour charges. I know the boiler was installed around 2009 and has worked fine up to around a month ago acording to owner, so thinking the F75 kit, that moves it over to the pump isnt required ?? The existing position of the boiler is upstairs in the cupboard which is currently the highest point of the system, batroom is downstairs so not even a towel rail higher . But like i say, its worked for the last 3 years, so not convinced the settup would contribute to this issue.

 

[armourer]

If you have eliminated the pressure drop.
Fit the F75 kit. It simply raises the height of the pressure sensor within the boiler and stops it blocking with crud.

No need to drain the whole system, just the boiler and takes about 15 minutes to fit.