Vaillent ecotech 28 pro

Ant62

Hi all..
We have an vaillant ecotech 28 pro which is 4yrs old a few weeks ago we where getting the f75 error code popping up...
A quick top up solved the issue be it only temporary.
Day before we went away on our hols the system did it again so i topped it up...
On our return i contacted BG wholm we have cover with and eventually he said that the pressure in the expansion vessel was low so he removed the existing air and represurised the vessel also the water pressure valve was faulty so he replaced that.
He also removed the pressure from the system this was two weeks ago.
On the time of the guy leaving the cold heating pressure was 1.3bar two weeks later it as dropped slowly to 0.9bar.

Now in august we had a new additional500mm x 500mm rad put into the bathroom as the towel rad just didnt warm up the room.
I removex some old floor boards and replaced them and then overboarded the floorboards ready for the tiler..
So i dropped the water in the heating and removed the two rads in the bathroom ready for the tiler.
The system was dropped 48hrs and then i put the rads back with new olives.
Before i overboarded the floor i chkd over a few days for any possible leaks from the new pipework for the new rad and nothing..
So now i find that im chking the pressure on a cold system on a daily basis.
Any ideas what is causing the drop in pressure..

Alex1983

How much pressure does it lose and how quickly?

If you had expansion vessel etc checked and you still loosing pressure then you have a leak somewhere.

You can check the obvious first, check all radiators and valves plus visible pipework when it's hot and cold. Also check the pressure relief pipe, which is the copper pipe that goes outside.

If you still can't find the leak you will need to get BG back to investigate.

daveyjp

OP Doesn't your boiler have a 5 year warranty?

Vaillants have had 5 year warranties for at least 6 years, so it should still be covered. If so, gat one of their engineers out rather than BG.

Ant62

Earlier i lifted the floorboards outside the bathroom and put an inspection camera under.
No leak detected from what i could see from the screen all is dry...

Plus another plausable explanation could.it be the magnatec ( no nonsense) is fitted on ou ours and as the thread is plastic and metal nuts could it be that..
As i now remember that i removed it to clean the magnet as i couldnt open the top...
I dont see any water upon the floor though in that vacinity.....

I also intend to give the two rad nuts a slight tigtening tomorrow....

I have also looked outside and theres no water from the pipe..

With regards to 5yr warranty that only applies to vaillant fitters.....

Ant62

"How much pressure does it lose and how quickly?"
Its gone down from 1.3bar to.0.9 bar in two weeks......

Ant62

Just been reading various posts on loss of pressure..
Post the interested me was the EV

Now when the BG engineer called he said the EV was low and needed repressurising...
He released the air ftom the EV and a bit of water through the PRV.
He then repressurised the EV with a foot pump and then switched the boiler on.
Immediately it told the water pressure valve needed replacing so he did that and said all was ok...

Now from what i have been reading whem your repressurising the EV the water as to be vented from the system then topped up to 1.bar
The BG didnt drop the water he just released some water through the PRV...

So should the EV pressure need chking again....

Ant62

Latest news..
I read some posts on other forums about adding inhibitor etc...
So i removed some water from the system and added 1lt of sentinel x100 and then topped up the water...

A week later the water pressure seems to have sorted its self out.....