Vokera Compact 28 losing pressure daily!

[neilianos]

I have a vokera compact 28 which is losing pressure at an alarming rate.
It needs topping up at least once a day.
No signs of leaks upstairs and have been under the floor downstairs and no leaks found either.
bareley lasts 12 hours without topping it up again. very annoying - the water must be going somewhere!!???
Any ideas please??
not too big on jargon and abreviations etc so please go slow and be gentle with me!

Many thanks

Neil

 

[Agile]

Put a bag or bottle over the pressure relief valve vent outside.

When refilled from cold to 1.5 Bar, what pressure does the gauge go up to as it warms up?

Tony

 

[pompeyal]

Good tip... I would go with the pressure releaf valve too, they can be such a pain in the rear, especially when people use them to drop the pressure on over filled systems. tempermental little critters they can be.

 

[MANDATE]

You need to start reading up on Expansion Vessels and how they work.
At a guess I think its highly likely that your vessel is faulty and has allowed the water pressure to rise to the 3bar required to open the PRV.
PRVs are also known not to seal fully once opened.
If the expansion vessel is the root cause of the problem, replacing the PRV will not resolve the problem.
Hence the reason why Agile is asking for details of pressure rise when heating is switched on.

 

[neilianos]

Put a bag or bottle over the pressure relief valve vent outside.

When refilled from cold to 1.5 Bar, what pressure does the gauge go up to as it warms up?

Tony

please please forgive my thickness.

What is the pressure relief valve vent outside?

Is it the big exhaust pipe thing or the little 15mm copper pipe that sticks out?

What will putting a bag or bottle over it do and do i need to put it over the valve before i put the heating on to see what pressure it goes up to?

Sorry for been thick

Neil

 

[BingoBongo]

Put a bag or bottle over the pressure relief valve vent outside.

When refilled from cold to 1.5 Bar, what pressure does the gauge go up to as it warms up?

Tony

please please forgive my thickness.

What is the pressure relief valve vent outside?

Is it the big exhaust pipe thing or the little 15mm copper pipe that sticks out?

What will putting a bag or bottle over it do and do i need to put it over the valve before i put the heating on to see what pressure it goes up to?

Sorry for been thickNeil

the 15mm pipe.have you seen water come from it?

put a bag over it to see if it is passing

after topping the pressure to 1.5 put the heating on..what does it rise to

if the pressure goes above 3 bar the pressure relief valve dumps water out that pipe,which has a washer that may not re-seat

 

[MANDATE]

The PRV is inside but will discharge water out through the 15mm pipe outside.
If you secure a plastic bag on the end of the pipe and see if water collects in the bag, it proves the PRV is leaking when it should be sealed.
The other requirement is separate. Water expands when heated, the extra volume created is forced into the expansion vessel. This compresses the air in the vessel (if there is any) cause the pressure to rise.
The water pressure should rise about 1bar when the heating is on and drop back when heating is off.
The pressure should not reach the 3bar required to open PRV, 1.5bar going up to 2.5bar or 1bar going up to 2bar is what is expected

 

[neilianos]

ok, heres the update, topped it up, the heating came on it went to above 3 and water dripped out of that pipe.

photos attatched

Neil

 

[BingoBongo]

ok, heres the update, topped it up, the heating came on it went to above 3 and water dripped out of that pipe.

photos attatched

Neil

check faq`s for repressurising expansion vessel,bobs yer uncle an all that jazz

 

[neilianos]

tied a bag over the pipe at dinner time as the heating is not due to come on until 5 ish. there is a bit of water in the bag after 4 hours. not massive amount though.

 

[neilianos]

I have taken the cover off and located the PV valve car tyre valve thing at the top of the boiler. pressed the centre pin and no water came out just air

Does this mean it aint buggered after all??????

 

[Axel]

RTFM.

You need to do it properly, the expansion vessel check / re-charge.

 

[neilianos]

i've read the faq thing

pressed the centre pin and just air came out.

i have a bike pump to pump it up, but it doesn't have a pressure gauge on it so dont know how much air i am putting in.

Is this an easy thing to do or do i need a plumber?????

 

[Axel]

You need to depressurise the system first.

Then leave the orifice wot you used to depressurise the system with open while you pump up the air side of the expansion vessel with a bicycle pump. (I notice my local plumbers merchant is trying to sell a glorified bicycle pump for £50!!)

1 bar should do it.

Thats around 14 psi.

Get a pressure gauge.

Get the manual pen type.

 

[neilianos]

Nice one mate thanks very much.

I've put that little fella on my shopping list for tomorrow!

How do i depressurise the system? just let all the water out of that drain tap thing on my lowest radiator?

then if i pump it up to 1 bar / 14 psi is that it?? job done??