No Central Heating Downstairs

[mark900]

Hi,

Here's the issue, I've been in the house ever since i was born( 28 years), and we've never had radiators downstairs Hot when the central heating is on, only the upstairs.( Strangely its all radiators downstairs with the issue)

The system we are running is an Ideal Mexico Boiler, expansion tub in the loft and a lowara pump in the airing cupboard( was a gronfus pump until that died)

The system appears to have an never ending air lock, which doesn't appear to pop/ budge. I've bled the radiators numerous times to get rid of the air. The return pipe underneath the pump ( i assume from the radiators) is barely warm compared to the output, i have tried to flush the system, a little crud came out but not heavily soiled.

How do i pop this airlock/ get these radiators downstairs hot ?

EDIT: system has been tried to be balanced with no luck

 

[Mottie]

Have you balanced the system?

 

[terryplumb]

If upstairs radiators have Thermostatic radiator valves ( TRV's) fitted ,turn them all off.
See if any downstairs rads now heat up. If they don't there is either a blockage or they are not plumbed in correctly.