Vaillant f75 code!!!

Mpedley · Feb 17, 2014

Ok, last week I added an extra radiator to my system.
it it had recently bee taken out of a friends house.
Since then I have had continuous problems with my vaillant ecotec 28.....
i have bled the system countless times, changed the pressure sensor, cleaned out the filter and checked the expansion tank pressure.

it will run with one radiator on but as soon as I turn the others on it crashes and shows the f75 code.

water temp is also erratic.

anything else I should try before calling out a engineer?

thanks, matt

TBServices · Feb 18, 2014

No. You've already gone too far

Killy Bing · Feb 18, 2014

Get an engineer in
you've likely done more harm than good already....

Ermintrude · Feb 18, 2014

Defo keep your hands out of the boiler - it might kill you.

Get a qualified engineer in. Don't take case off boiler in future. It's dangerous and can very easily lead to carbon monoxide poisoning.