System pumping over & noisey radiator

[bakerboy1977]

I have 2 problems with my CH. I'm thinking they are realted. I'm hoping you can help.

1. When CH goes on in the morning the bedroom radiator gurgles for about 10 minutes. I've bleed all radiators multiple times, no air comes out. Any ideas?

2. When the CH has been running for over 5 hours, water starts pouring intermittently into the header tank in the roof space. Is this normal? I've tried turning the pump down to number 1 - no change.

Please help! I've tried all I know and can get no-where

 

[twgas]

i would think there is a partial blockage in or around the cold feed/open vent connections.

or of course they could be piped wrongly, in which case you may need only to alter the pipes.

 

[bakerboy1977]

i would think there is a partial blockage in or around the cold feed/open vent connections.

or of course they could be piped wrongly, in which case you may need only to alter the pipes.

Thanks for your reply Mick.

Where are the cold feed/open vent connections? Is there any way I can check for a blockage or clear one?

This problem has only happened since I had TRV's fitted. They are Myson 2 way valves. Could this be part of the problem?

 

[twgas]

follow the pipe that comes out of header tank, (cold feed), near where it joins the system should be the open vent (the one that is looped over the header tank).

the trvs may be causing the pumping over if you've got no by-pass.

 

[bakerboy1977]

I'm going to try leaving one of the thermostats fully open. At present all are at '3'. Maybe if one is fully open all the heat/pressure will have somewhere to go when the CH has been on for several hours? That's my uneducated theory... we'll see...

 

[bengasman]

Around 80% of open vent systems suffer from sludge build up due to poor maintenance.
With the symptoms that you describe, we are looking at 95% probability. Sometimes it is so bad that not even a powerflush with phosphoric acid can cure it and cutting out and replacing pipework is the only solution.

 

[kev_1911]

your plumber should have known to leave 1 rad without a trv for by-pass purposes if your pipework does'nt have a built in by-pass,drainning down to fit them may have caused a blockage,would have been an ideal time to give the system a full flush.