3 out of 12 rads not working after re-filling system

[whodareswins]

I have fitted a towel rail in place of radiator in bathroom - on re-filling system 3 out of 12 rads won't heat up. I suspect an air lock but all rads are full of water (from vent screw)

I have :

Bled Rads
Bled Pump
Closed working rads to divert pressure to non working etc

Can't seem to shift air

System is fed from heat and expansion tank (not combi)

Is there any other point at which air can be purged from system? there is a pipe terminating near the copper cylinder in airing cupboard which appears to have a "screw top"

Two things you should know:

Downstairs radiators fed from above down wall in 15mm pipe - no drain cock on rads so these remained full of water when system drained.

One downstairs radiator currently off wall/ disconnected for redecorating

Will either of these factors affect re-filling?

The cold rads are : The one used to drain system (lowest) one downstairs rad (fed from above) one upstairs rad (opposite end of house from downstairs rad BUT DIRECTLY ABOVE RAD USED TO DRAIN SYSTEM)

Upstairs rad in main bedroom so "her indoors" starting to nag!

 

[Bahco]

There is a pipe terminating near the copper cylinder in airing cupboard which appears to have a "screw top"

That is a bleed point. Open it until water escapes.

Also consult the FAQ, 5th post down for rad problems