Possible air lock in Combi Boiler

[thewigster]

Hi, im sure you all get lots of posts for this but ive read a few but nothing seems to help my situation.

Basically i have a Gloworm Combi Compact 75e with a filling loop. I disconnected 2 rads to change the plumbing. Got CH working again without the 2 rads (after several bleeding sessions) to remove air lock. Happy Days

However, I connected up one rad, tried bleeding and connected the 2nd rad but boiler refuses to fire up and ive lost count how many times ive bled all rads. I also tried letting out water from one rad via hosepipe and topping up with filling loop but still no luck. Ive got to the satge that no more air is coming out of any of the rads. Ive maintained the pressure at 1bar.

The only abnormality is that one of the rads ive reconnected hardly lets any water out (but lets loads out via drain cock). After switching the boiler on, the boiler then shuts itself off and have to press the reset button to turn it back on. The boiler doesnt even try to ignite.

Any help would be appreciated as im getting bored now going around all these rads

Dave

 

[bellairaphon]

are both valves open on the radiator trv / lockshield. room stat calling for heat any symbols on your boilers illuminated? does your hotwater work

 

[thewigster]

Thanks for the response.

Yep both valves are open, there isnt a room stat and there is not hot water either. The boiler just resets as soon as the hot water is switched on.

All the lights are ok on the boiler except when you either turn on the hot water tap or turn on the central heating. Ive checked the manual and it says there is a air pressure release valve inside the boiler unit so i wold have thought any air trapped would escape via this method.

Will try and do some more bleeding and see what happens!

 

[Slugbabydotcom]

Just while you are getting it going, take the pressure up to about 2.3 bar.
Drop it back down as the system starts to work. This will compress any air bubbles and make them easier to be pushed round the system.

Have a look in the manual sometimes theres a manual air vent inside the combustion chamber or at the top of the boiler somewhere.

Haha Just spotted it

air pressure release valve inside the boiler unit so i wold have thought any air trapped would escape via this method.

It will be a manual one or if its automatic it might need the cap loosening

 

[thewigster]

Thanks for the prompt reply slug.

Tried raising the pressure and bleeding but no luck. Checked the manual for the location of the automatic air vent (right behind a big pipe) but was just able to turn it a little with one finger. A small amount of air came out, so i went round the rads and air now released from most of them. And the boiler now fires up! So much for an automatic air vent (doesnt sound very automatic to me) lol.

Cheers for the advice slug u little beauty!!!