Glow worm filling loop......

[beechams]

hi there, im after some advice on my glow worm 30cxi boiler! Recently we had a drop in pressure on the boiler it was showing 0.7 and the red light was flashing, i followed the instructions which were on the casing but still nothing happend, i then read the installation and servicing manual and realised that i probably needed to fill the system back up using the filling loop, when i did this there is water coming out from a brass valve on the far left of the boiler, i have taken the housing off and flapped down the control panel and i can see where the water is coming from it almost looks like a bleed valve, i have asked a few people but no one has been of any help, on the 30cxi do you have an external filling pipe which connects to this valve which is leaking or is it the the valve is broken or some one mentioned an intergral filling loop which is done with a key....im just a bit confused as to what the problem is, if some knows how to fix this i would appreciate the advice or even be able to point me in the right direction.

many thanks

 

[Deleted member 105431]

the disconnector (brass valve on l/h/s) can dribble during topping up but thats not a problem.

 

[beechams]

hi there, thanks for replying so soon....you got it in one its the valve on the left hand side, the only problem is when i turn the blue tap and it only has to be a slight turn the water ****es out of the bottom of that valve its like there should be a hose attached to it....maybe this is right maybe i havent been patient enought but i can se that any of the water will be getting into the system it all seem to come out the bottom of that valve, any ideas?

appreciate you time

 

[Gasguru]

The device leaking is designed to prevent backflow of heating system water into the mains drinking water. It is fitted to this model of boiler for compliance with water regulations since a permanent filling loop connection is made. Glowworm tried to be too clever and the filling system doesn't work particularly well. Normally these backflow devices would be connected to a drain so leakage is not a problem but Glowworm fail to mention that since it would add to installation cost.

There are a few flaws with the device.....

The mains pressure must be somewhat higher than the system pressure required ie for 1 Bar system pressure the mains may need to be 1.5 Bar....this is a problem in many areas of the country where mains water is low.

The valve seating inside can scale up resulting in significant leakage during filling.

The initial check valve sliding assembly inside the device can jam discharging water to the drain port.

Hold a bucket under the device and allow a significant amount of water to flow...open and close the filling valve several times....this may clean out the valve.

If there is still significant leakage I suggest you have a conventional quality filling loop fitted under the boiler.