A friend has a Glow Worm Ultimate (wiring diagram for models 30 – 60ff inside so presume it’s one of those).
It has two 1″ pipes going into the top, one of which has a valve/attachment on it and 1 22mm pipe underneath. He has had to change a bleed valve on one of the upstairs rads so connected a hose to the afore mentioned hose connector atop the boiler and effectively drained the upstairs roads…all good. He now, however, cannot get the system/ radiators to refill ..
Presume it’s a gravity fed boiler..

Any advice to get the rads heated?

Bump…,

Might be an airlock somewhere.

I take it he has been opening the air vents on the rads?

That’s are far as I can go on my limited knowledge, I am not a gas engineer, I just sell the bits to the people that are.

If he’s struggling to fill the system I would suggest he is out if his depth.

could be a blocked cold feed, airlock, or he might have sealed system

Tell him to put his hand in his pocket and hire a professional:-)