Vaillant Ecotec Pro 24 boiler issue

[dazzyboy10]

HI there,

For some random reason, our boiler decided to stop working and is giving us an F.75 error code which according to the serivce manual, relates to "No pressure rise was detected on turning on the pump" and states the causes as:
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.

Unfortunately i am clueless as how to sort this and as we are private tenants, not really wanting to attempt to sort this myself and our landlord is unavailable to sort it either.

After searching the web I came across a similar problem advising to keep the hot tap running and turning the boiler on/off a few times but for us this didnt work.

Also the bar pressure states at being 1.1 but the dial shows at zero so contemplating that the system may need filling up but this has also put us at a dead end as the boiler is setup in a different way as to how the service manual shows.

This is quite important as we have 3 young children and need to get this sorted asap.

Any help would be greatly appreciated

TIA

Also I have tried contacting Vaillant themselves for technical advice but the phone number they provide is dead.

 

[SimonJohns]

Your going to need to contact you ll. this will be a costly repair. And will require a gas safe registered engineer to fix it

Be sure to check their id when they arrive

 

[dazzyboy10]

So it couldnt just be a simple water top-up thats required then seeing as the bar dial is reading zero.
This has happened before but the landlord fixed it but didnt show us how to. I dont know if its worth mentioning or not but we have recently noticed a strange whistling sound coming from one of our radiators. Couldnt be related could it?

 

[fixter1]

top up to 1/1.5bar

 

[dazzyboy10]

Problem being is that i dont know how to top it up as as i mentioned previously, the setup is different to what the service manual shows so i am unable to do it

 

[P J F PLUMBING]

It's prob the low pressure sensor it's a common fault

 

[dazzyboy10]

But the strange thing is, is that when i press a certain button on the boiler it will display the bar pressure and it fluctuates between 1.0/1.1 but the dial on the front of the boiler states its 0

 

[P J F PLUMBING]

The sensor is not registering no pressure but the boiler is

 

[dancinplumba]

should have a filling loop somewhere, its a silver braided flexible hose usually near the boiler, could have levers on it or a slot for a screwdriver

 

[dazzyboy10]

i have managed to find the filling loop as we had a response from our landlords secretary but i think we have put too much water in as was advised to put the dial at half way and the bar pressure is showing at 1.8