Expansion Vessel losing all pressure in hours?

[jtsplumbing]

All sounds very strange ? can you put up some photos ? and some of this black pipe !

 

[Cluelessnewby]

Hi @jtsplumbing - I've attached two of the black pipe that comes out of the boiler/utility room.
Hope it makes some sense to you, I have no idea with plumbing at all, so it's like trying to speak Dutch

 

[king of pipes]

You need to get a engineer in bud to many things it could be . cheers kop

 

[Cluelessnewby]

You need to get a engineer in bud to many things it could be . cheers kop

I was worried that'd be the answer, but I think I'll have to.
The guy that fit the EV and UVC is back to install a complete bathroom next week, i'll get him round for a look before then...

 

[Harvest Fields]

I was worried that'd be the answer, but I think I'll have to.
The guy that fit the EV and UVC is back to install a complete bathroom next week, i'll get him round for a look before then...

Probably for the best mate

 

[Paul Styper]

Hi All,

Bit clueless here, but wanted some advice if possible.

We had a new 200ltr unvented system installed recently. All seemed fine, however the CH kept turning off and rads going cold.

I checked the EV in the loft, and it's pressure gauge had dropped to 0. I opened the valves up and filled back up to 1.5bar (on advice of the fitting plumber). This got the rads going again, but two hours later it's back to no pressure/rads off?

When the rads came back on originally, I could hear them bubbling away (filling up?) quite loudly. I bled them, two released air...

The only thing I've done recently since the install is turn the gauge on the Worcester boiler up from 1/2 way to full.. could that be a problem?

Overflow seems fine, no water came out the EV when I checked...

Plumbed said air possibly escaping the system somewhere, or water leak in the ground floor pipes, but could try a sealing solution.

He's v.good, but is there anything obvious I should look for/try before rushing them back out? It seems a bit extreme the EV drops pressure in two hours?

Thanks,
CN

Sounds like the diaphragm in the pressure vessel could be ruptured. What happens then is that there's nowhere for the expansion when the system heats up so it dumps the excess pressure through the pressure relief valve to outside. When the system cools down the pressure also goes down with it usually to zero thereby shutting down the boiler. The easiest way to check is to poke a small screwdriver in the schrader air valve (like a car tyre valve) on the expansion vessel and push it in. if water weeps out of it, the diaphragm has ruptured.

 

[dan_the_plumber]

If you press the pip down on the expansion vessel and water comes out, the expansion vessel is knackered.
If not, pump expansion vessel back up to system pressure (typically 1.0 bar)
The Shraeder air valve on the expansion is probably loosing air. You can buy a Shreader valve extension tube from city plumbing for £11.00. Stick that on, it's like replacing the valve effectively. Job done.
It is probably an engineer job though, since there are a few finaties, draining the boiker etc.

 

[Harvest Fields]

If you press the pip down on the expansion vessel and water comes out, the expansion vessel is knackered.
If not, pump expansion vessel back up to system pressure (typically 1.0 bar)
The Shraeder air valve on the expansion is probably loosing air. You can buy a Shreader valve extension tube from city plumbing for £11.00. Stick that on, it's like replacing the valve effectively. Job done.
It is probably an engineer job though, since there are a few finaties, draining the boiker etc.

Just because there is fluid inside the vessel. It does not necessarily mean the diaphragm has gone. Sometimes condensation builds up inside the vessel and just needs to be drained out.

 

[Cluelessnewby]

Hi All, just to update you following your comments, the plumber came back out, released air from the pump he'd installed, switched all bleed valves around to make it easier to bleed and took all air out of the system, recharged it all and added 3 tubs of sealant to the system. Appears to have done the trick thankfully!

 

[dan_the_plumber]

Just because there is fluid inside the vessel. It does not necessarily mean the diaphragm has gone. Sometimes condensation builds up inside the vessel and just needs to be drained out.

Never heard of that before. How does the moisture get into the air side of the vessel to begin with?