Combi boiler not firing

[Kingdave]

Hi,

I have drained my water system and installed a new expansion vessel and pressure relief valve to my very old Combi-boiler.

However on refilling the system and bleeding the radiators the boiler will not re-ignite. If I turn on the central heating system or the hot water then he boiler starts up and seems to be trying to fire but the flame just will not appear.

Think I may have a bit of air in the boiler but do not know how to get it out! Doesn't help with an 8 day old child in the house!

The boiler is a Biasi 28S (very old I know but not at the top of my list for replacement) and has an automatic air vent but not sure if it is functioning, or if it is air at all.

Any help appreciated, thank you.

 

[dcawkwell]

Does your old boiler have a pilot light that needs to be relighted.

 

[Kingdave]

No it does not have a pilot light, normally it justs lights automatically but not tonight of course. The noise does not seem normal either, it didn't sound like that before I drained the system.

Just realised I didn't mention that in the first post, when I try and fire the boiler it makes a horrific gurgling noise.... Nice.

 

[dcawkwell]

undo the large pump screw in the middle of the pump and place a good towel under it. With the pump running you should get air being bled out of the system and once the flow sensor detects some flow it should fire.
There may be some water running out too.

 

[Kingdave]

OK thanks I will give it a rattle now, just had a look at the auto air vent and it looks a bit ore-war so not sure if it's doing its job at the moment...

 

[Kingdave]

Please ignore my last post if you saw it, I have had a look inside the pump when it is on and it seems to be spinning no problem however there was only a dribble of water that came out of it, should there be a lot more???.

Cheers,