Microbore heating advice please!

[madhairmum]

Have recently moved house and have microbore heating system, its a newish combi boiler.

Have found 1 manifold, which we think is serving all downstairs rads. Is it likely that there is a second manifold for all the upstairs rads?

The problem is that some radiators get hot, others luke warm. Neighbours have similar systems and have suggested a power flush works for a time.

So far we have, bled rads, balanced them, taken two off and flushed with a hose, turned all but one of the problem rads off and bled the problem one.

Problem still persists...what next please? Any help or suggestions gratefully rec'd!

 

[gas4you]

In your case it sounds like the manifold its self is blocked.

Power flushing is not very effective on microbore systems.

If you have drain points on each rad, try connect a hose, connected to an outside tap and 'back flushing' the pipe work and manifold.

If you have a sludgy system, then this could block the flow outlet on the manifold as it is so small, back flushing may shift this blockage.

The real answer is to change to small bore pipe work, or at least install new manifolds.