Cold rads

[scorpio stu]

Hello,
We have 3 cold rads 2 upstairs and 1 down that are completely cold.The downstairs one eventualy gets hot but the upstairs both stay cold.The rest of the radiators are fine.I have tried bleeding them but seem to only get water coming out and not air.Should this be done with the heating on or off as I have tried it with the heating on but not off yet.
It is a combi boiler and all the rads have thermostatic valves as well as the temperature control in the hall.

Cheers

 

[John506]

Probably sludged, take each individual radiator off, and take it in the garden and hose it out, you will find it's full of black sludgy water.

Doesnt matter when you bleed them, just make sure pressure is topped up.

 

[finley1984]

hi has this problem just started or have you had the system drained down to do someting.

 

[crockett]

Could also be the valves stuck closed as well, through lack of use in the summer.

 

[QuickQuestion]

Hello,
We have 3 cold rads 2 upstairs and 1 down that are completely cold.The downstairs one eventualy gets hot but the upstairs both stay cold.The rest of the radiators are fine.I have tried bleeding them but seem to only get water coming out and not air.Should this be done with the heating on or off as I have tried it with the heating on but not off yet.
It is a combi boiler and all the rads have thermostatic valves as well as the temperature control in the hall.

Cheers

Thermostatic valve pins may be stuck, and system may not be balanced correctly. All depends if the problem has just happened or got gradually worse.

 

[scorpio stu]

Thermostatic valve pins may be stuck, and system may not be balanced correctly. All depends if the problem has just happened or got gradually worse.[/quote]

Well done,I took the valves off and the pin was still down.Pulled it up gently and hey presto...hot rads.A bit of wd40 later and put the valves back on and working like a dream
Thanks for the help.