Is my pump really K*******D?

[moneypenny]

I have a glowworm gravity fed back boiler. In the summer we had to have a new hot water cylinder fitted in the loft, since then the central heating has worked fine but we cannot get any hot water.

Last week a plumber came and banged about for a bit said he had managed to remove a small amount of air from the system but thought the pump had failed ( no vibrating pump half cold half hot) and needed replacing even though the central heating is working fine.

After he left the water heated up fine for two days and is now cold again.
The same plumber is due back to try again can you help......PLEASE

Thanks

PS. In the summer to heat hot water only we have to switch off the upstairs radiators as these still get hot, does this mean we need a check valve? if so one was never fitted as this has been the case since the heating was installed.

Again many thanks

 

[PEDANTICVINDICTIVEMAN]

Still got air in the pipes to the cylinder, your upstairs rads are working on gravity, I would either fit thermostatic valves on the upstairs rads or carry on as before rather than upset an old system with check valves, if your downstairs rads are working the pump is working.

 

[moneypenny]

Thanks pedanticvindictiveman you have confirmed what I suspected, about the air I mean, I did tell the plumber this but he didn't seem too impressed. Now I need to find out how to bleed the system.

 

[sharan17a]

Could the pump be seazing up? Mine was when I moved in - it hadn't been used for ages. I opened it up and turned it manually with a screwdriver to get it going and then it was fine.

If yours was working for 2 days and now is not, it's probably not seazed, but might be on its last legs.