I’ve bled the radiators and two of them are still stone cold even though they spew out water through the bleed vent. The system is a pressurised system with a Tribune 200ltr tank, the pressure is fine and have re-filled it.

One of the radiators is the bypass radiator in the lounge (without a TRV) and the other is in the kitchen. I started at the lowest point in the house with the heating on, most of them are now bouncing of the walls and the other two are stone cold.

Any ideas??

air lock somewhere, or sludge build up blocking the flow?

do it with the heating off the pump could be moving the airlock around or ingesting air potentially.

You start at the highest point away from boiler.
That’s the way I was taught…..

If both sides of both rads are open, there’s no stuck trv’s on either rad, and they’re both full. Then turn the rest of the rads off, trv’s closed will do, and stick the heating on. If they still won’t heat, you’ve probably got a blockage.

I’d be disconnecting legs and pulling water through from there.

turn all the rads off except for one of the cold ones and see how it goes from there.

But if he’s bread them and water coming out surely they are not blocked?

Do it again with the pump off. Make sure the valves are open at both ends. Make sure the supply to the CH circuit is active – either the small tank in the attic or the pressurising loop below your boiler.

If a rad still doesn’t work, turn off the valves, loosen the valve to rad connectors, lift the rads (they are heavy) off the brackets and swivel them down to the floor. Undo the connectors fully and turn the rads upside down then take them out to the garden and allow all the filthy black sludge to drain out, then hose it out. Keep those rads upside down indoors though, unless you want black splodges all over the floor.

bren2709 – Member
But if he’s bread them and water coming out surely they are not blocked?
POSTED 2 MINUTES AGO # REPORT-POST

I’ve been doing this for 16 years. 🙂

Radiator has two pipes, if one is blocked, then water won’t flow, and therefore won’t heat, but if you open a bleed, then the leg that’s not blocked will still feed the rad. If both legs are blocked, then the rad wouldn’t fill.