Help with Expansion Vessel

[afclegend81]

Hi all,

I have a Flexcon 8l expansion vessel located in a small cupboard not far from under the boiler.

Basically i was bleeding a radiator and noticed the pressure drop, so i opened the ballcock to let some water into the expansion vessel to fill the system, i have to turn a small black cap to let this water through to the vessel. When i had finshed i tighted the black cap up and closed the ballcock, there is now a constant drip of water coming from the cap.

When i turn the cap all the way back it does not completly remove, so i cannot see exactly what is causing the drip.

Any help would be great need to get sort this asap as i'm working away from home as of tommorrow so the GF will be left with the problem

 

[muggles]

This 'small black cap' wouldn't happen to be covering a bicycle-pump type fitting would it?

A pic would be useful

 

[afclegend81]

hi m8,

Pictures added through profile,

Not sure whats behind the cap, i can unscrew it only so far then it wont budge.

 

[Gasguru]

If the black lever is now leaking it will probably have to be replaced.

When you put the heating on carefully look at the pressure gauge...switch off if it gets to 2.5 then read the FAQs...I can guarantee the expansion vessel will be flat.

Also another picture of the connections to the vessel would be useful...it appears the safety valve connection has be capped (V dangerous) unless another safety valve is plumbed in elsewhere.

 

[afclegend81]

Hi m8 cheers,

The black lever is fine the problem is at the black cap located at the top of the vessel, when there is pressure in the system there is a continuos drip from it, i cann't seem to remove the cap to further investigate. There is a safety valve above the boiler located next to the pressure gauge.

 

[Gasguru]

The black cap is connected to the schrader valve. It is not uncommon to find a little water in the base of the expansion vessel. By depressing the center pin of the valve you can evacuate any residual water. Any more than a a tablespoon though and the vessels probably stuffed. As I said the vessel has probably never been re-charged with air so the diaphragm may be perished...FAQs for more info.

 

[muggles]

Which cap are you turning? Any chance of a close-up from a different angle? Is it the cap itself that's leaking? You shouldn't have to do anything to let water to an expansion vessel, as there shouldn't be any valves between it and the system

 

[afclegend81]

Hi m8,

couple more images added.

The black cap seems to need to be turn just a bit to let water in allong with the black lever open, then turned a bit to close it along with the black lever closed to stop water flow.

cheers

 

[muggles]

I reckon it's just a seal gone, the cap should come out with a bit of force but if it won't you might need a new valve. Don't try to take it out with the system under pressure though, you'll get very wet

 

[afclegend81]

Ok thanks all for your help i shall have a look at it,

thanks again

 

[Gasguru]

Sorry...misread your previous posting. The small black cap you are turning is test point plug between the check valves..probably the O ring has failed. You should not need to turn this to allow water through. If the check valves are working correctly the water should stop dripping eventually and you can remove the plug and reseal with PTFE tape.

 

[afclegend81]

ok, i'll repressurise the system and see what happens, trust me to bugger up a test plug doh!!!

thanks for your help again,

 

[roguetrader]

as above, its a test/verification port on the check valve. make sure the black lever on the filling loop is properly seated in the off position (90 degrees to being inline.) then follow above advice!!

 

[afclegend81]

silly question perhaps,

how do i add water to the system? I turn the lever on the pipe which is connected to the mains, this is ok, where would the other lever, valve, be to turn to let the water come in. All there is, is a round black cap with a square hole under it, this is on the other end of the silver braded tube coming in from mains?

thanks

Untitled

• afclegend81
• 30 Sep 2008
• 1

Black cap on right which has small leak

Untitled

• afclegend81
• 30 Sep 2008
• 1

Black cap on right which has small leak

Untitled

• afclegend81
• 30 Sep 2008
• 1

Untitled

• afclegend81
• 30 Sep 2008
• 1