Central Heating Problems

[supra TT myster]

Hi

Basically having central heating problems, no hot water or radiators hot.
Boiler comes on for a few secs then off again, i belive this could be to do with air, all the radiators downstairs have water comming out of the air valves but none of the ones upstairs have any signs or water or air comming out from them? What does this mean?

I have just drained the system again, and filled it up again from the bottom upwards to try and push the air out, all radiators had water comming out of them as i closed the valve one by one, and also that pipe that goes just about the pump, put it all back together and swithed it on and boiler came on then off again, (pump is always running by the way and has been making some noise but i think that is because the water is not flowing through it and it goes dry but im not sure?) and come to bleed the air just to see what is happening and again water out of the ones downstairs but nothing out of the top ones nor that pipe that goes in the air from the pump with a valve on the top??

Any ideas to whats going on??

cheers

 

[oilman]

Is it an open vented or closed system?

If it's open, then the feed pipe may be blocked.

If it's closed then there's not enough pressure and the air pressure should be checked first.

 

[supra TT myster]

i think it is a open vented, how can you tell?? Its not presurised as there are no gauges on the boiler, has a expansion tank if that make a difference? If it is the cold feed, is there a way of trying to unblock it? I have found the pipe for it, just under the pump and goes to the bottom of the expansion tank?

 

[oilman]

That's lucky, you can check the water supply without having to cut things first. Turn off the boiler and pump. Turn off the valves at top and bottom of the pump. Undo the nuts on the pump and take it out. Open the valve at the bottom of the pump, and be prepared to catch the water. If water comes out, and the header tank starts filling, it looks like it must be another problem. If water doesn't come out, the pipe's blocked.

You'll need to cut the pipe near where it joins the circulation pipe. Then shove something up it (or down it), to clear the blockage.

 

[supra TT myster]

hi

just tried all that and there was no water comming out of the pipe when i took the pump off so looks like it is blocked, thanks for the help, will try and unblock it tomorrow.

cheers