I have a Glow Worm 65-80 boiler system, pumped rads and thermo-syphon hot water. I drained system to move and replace the bathroom rad. I refilled the system and bled all rads. Now only downstairs rads work. When I bleed upstairs rads I sometimes get a little air out but the hot water is not reaching these rads. Also the syphon hot water system is not heating the water in the cylinder. I obviously have air trapped somewhere, I'd guess it may be in or above the boiler. As I have tried bleeding everything I can, where should I look next please?
I can't find any way to bleed the boiler itself.
I can't find any way to bleed the boiler itself.