Vaillant Ecotec 832 pressure rise with CH on

[Sandeep89]

Hi Guys,

Needed bit of help on a Vaillant Ecotec 832 which has a pressure issue. The boiler pressure is rising when the CH was running. I have checked the expansion vessle static and charge is showing 1bar on my pump, which I believe means the vessle is good or best to still recharge again? Checked the shrader valve not leaking and no water coming out when pin pushed in.

The boiler has internal filling loop and I removed the filling hose. The filling loop on the flow side is dripping a little. Could this be the cause behind pressure rising as water is letting by into the CH side.

The customer said pressure went to 3.4 bar and display was flashing. I have checked the PRV and it is not letting out water.

Any help would be great. Thanks

 

[ShaunCorbs]

Did you check the flexi isn’t blocked ?

 

[Last Plumber]

If the filling loop is passing then yes it will cause a rise.
A plate heat ex with a leak from secondary to primary will do same.
Other things that cause a rise could be a blocked pipe leading to the exp vess or an undersized vessel?

Need to know a bit more really.
How old is the boiler?
Is this a new fault?
Does the pressure rise when the boiler is not running? or only when heating is running

 

[Sandeep89]

If the filling loop is passing then yes it will cause a rise.
A plate heat ex with a leak from secondary to primary will do same.
Other things that cause a rise could be a blocked pipe leading to the exp vess or an undersized vessel?

Need to know a bit more really.
How old is the boiler?
Is this a new fault?
Does the pressure rise when the boiler is not running? or only when heating is running

The boiler is 1 year old. Yes the fault is new only started 2 days ago. Pressure rises only heating is running not when the boiler is off. However when the boiler cools down the pressure stays around 1.8 bar and doesn't come down to 1.5bar to which the boiler is pressurised.

 

[Scott_D]

Have you checked the internal pressure gauge?
How many rads on the system?

 

[Sandeep89]

Have you checked the internal pressure gauge?
How many rads on the system?

Internal pressure gauge was in the red when the issue was seen. There is 7 rads

 

[Scott_D]

How strange
Just to confirm you checked the expansion with the boiler drained and the drain off still open?

 

[Sandeep89]

How strange
Just to confirm you checked the expansion with the boiler drained and the drain off still open?

Yeah so isolated return and flow, drained down boiler and left drain off open. The static reading was 1 bar.

Yeah I know, I am going to leave the filling loop hose off and then run the heating and monitor to at least eliminate the filling loop.

Talking about vessles total random question but had a boiler few months trying to recharge the vessle however no water was coming out from the drain off when pumping the vessle. Any ideas on that.

 

[Last Plumber]

Pressure sensor reading correctly?