refilling Alpha 240E combi sealed system

[Tomtom08]

I've drained a sealed system and replaced the valves on three downstairs rads and now need to refill. Before I start (apart from the obvious, like venting the rads), I need to know how to avoid airlocks in the pump/boiler. Previous posts have mentioned opening the pressure relief valve to draw water through, others have said it's no harder than just filling from the closed loop to bring up to pressure. Any suggestions?

 

[Gasguru]

Read the FAQ's on re-charging the expansion vessel.

Never use the pressure releif valve to drain water - it will leak afterwards.

Check the cap on the brass auto air vent on the pump on the right hand side of the boiler is loose to allow air to vent. Keep an eye on it - they often leak.

Pour in some quality inhibitor to prevent corrosion (no cheapo diy shed carp)

Fill to 1 Bar and bleed rads topping up as necessary.

Turn gas off at meter.

Turn on heating and open/close hot tap every 5 seconds or so until pump runs quiet.

Turn gas back on.

Balance radiators (see FAQ's)

Once system cooled down bleed rads and top up pressure.

Most systems don't get airlocks.

 

[Tomtom08]

thanks very much indeed for that - v swift and v useful.