Ideal Mini C28 New Expansion Vessel, Loses Pressure, No Leaks

[j1cta]

Hi Guys,

Here's and good one.

Called to the above which had a leak on the boiler. Closer examination revealed that the expansion vessel had a blown diaphragm and was full of water, and started to leak.

Replaced the expansion vessel, re-filled the system and fired her up.

All is well. CH working a treat and DHW reasonable. No issues. Nicely running at 1.5Bar.

2 Days later, the customer calls to say the boiler is off again.

Returned to find no leaks, no system pressure, expansion vessel fine.

Topped up the pressure and checked again for leaks. No issues with the PRV, filling loop installed in reverse so not going back into CW supply and definately no leaks in the property. All runs are exposed with nothing under the floor and no marks on the ceilings.

The only thing out of the ordinary, is that the thermostat is turned to 10Deg overnight and then back to 20Deg in the morning when they get up.

Q: Where did the pressure go to? or is it a faulty pressure gauge potentially affected in the initial incident?

 

[Billy Bob Bob]

re check the prv may be opening due to damage tie a bag on it see if it fills with water,check your ev pressure even though its new may be flat

 

[j1cta]

EV Pressure is perfect. Checked before I installed and again when back on site.

Bag on the PRV is a nice touch!!!

 

[j1cta]

Gas Man,

That bag on the PRV exit is a class act. Dropped one on the other day and sure as Bob's your uncle, there is was.

Fitting the new PRV tomorrow.

Good call.

 

[wnjswozo]

check chrome hose to ev,these sometimes crud up so water cant expand into ev,causing prv to open