System Drain Down

[novicegas]

So I put a new drain cock valve on my lowest radiator today, my question being why did my open vent system take quite a long time to drain down and a hell of a long time to fill up ?

On the fill up, out of nine rads, the second one when bleeding i could barely hear a tiny tiny hiss. I completely took out the bleed valve and literally no water coming up at all, checked the f and e tank as had filled with x100 and was completely full. Kept on revisiting the rads to bleed and they would build up a tiny bit of pressure then stop. Eventually got them all filled, bout an hour in total!

Any ideas on the problem? does it need a power flush or is it badly installed pipework? Victorian terrace house.

Many thanks.

 

[stani]

Muck in the bleed valve hole try pushing a cocktail stick in to clean the hole but make sure you have cloth with you because if it is blocked and you have got the bleed nipple in your hand they never go straight back in, and you do not have enough hands to do the job.

 

[scotty plumber]

Is it fed from solid-fuel? Is the pipework done in microbore?

 

[vectra65]

prob blocked feed pipe from tank blow through expansion pipe with system turned off see if its easy to blow back into tank

 

[novicegas]

Cheers guys,

Its a Natural Gas system, normal 15mm copper not micro bore. All the radiators took a long time to fill so don't think it can be the bleed valves, If the feed pipe from the tank is partially blocked how can I clear it? Fill with cleanser, leave for a couple of weeks then powerflush, or is there an easier option.

Many thanks for all the respones

 

[ManchesterGas]

Cut it out and replace I'm affraid. Check where the blockage is with a magnet.

 

[LeakFinder's]

500 you should put that in the hints and tips section never though of traving the blockage that way.

 

[dancinplumba]

500 you should put that in the hints and tips section never though of traving the blockage that way.

no offence to 500 but this is a well known way

 

[novicegas]

Further problem or maybe an associated one, the top two radiators are stone cold, have bled them so they are full, all others are working well, any ideas???

Cheers

 

[REDSAW]

systems sludged up.
how clear was the drain off?.