One Cold Radiator

[gsandi]

Can anyone help? This rad is driving me mad. it is downstairs and it will not heat up.
bled rad and it got warm but then started to cool down again.
there are three rads downstairs one in passage on in front room and the one that will not heat up is in backroom downstairs.
two rads upstairs - heat up fine. the rad in the bathroom is further away from the boiler and it heats up fine. The rad downstairs for some reason the water will not flow down to it.
took rad off and turned water on and opened up flow valve - pressure seemed okay. opened up return valve and the pressure seemed greater!
tried looking on the net and i cant find anything.
any help would be appreciated.

 

[GasSafeTony]

Its possibly air locked...Close all other radiators off and leave the one not getting warm open....see if you have any joy.

 

[gsandi]

Its possibly air locked...Close all other radiators off and leave the one not getting warm open....see if you have any joy.

Cheers I will try this tomorrow and let you know how i get on.

 

[GasSafeTony]

Its possibly air locked...Close all other radiators off and leave the one not getting warm open....see if you have any joy.

Cheers I will try this tomorrow and let you know how i get on.

Also, if it not a combi boiler and there's an indirect cylinder (copper tank in airing cupboard), make sure you close the gate valve on the return pipe to help force the air lock out (that's if it is an air lock).

 

[gsandi]

Its possibly air locked...Close all other radiators off and leave the one not getting warm open....see if you have any joy.

Cheers I will try this tomorrow and let you know how i get on.

Also, if it not a combi boiler and there's an indirect cylinder (copper tank in airing cupboard), make sure you close the gate valve on the return pipe to help force the air lock out (that's if it is an air lock).

Tried this last night as this is really frustrating me. All rads shut off with only the one that does not heat up left on and it will still not heat up. lifted floor boards up and from the boiler we have 22mm pipe which travels about 6-7 feet away from boiler then it reduces to 15mm. With all rads off and only the problem one on, the pipes under floor boards were just heating up to where they reduce to 15mm. All the rads tee off from the 15mm pipe-work and travel horizontal for a few inches and then 90 degrees down to the rads. The rad that is not working tees off horizontal for about 8 inches then 90 degrees horizontal for 4 inches then 90 degrees vertical down to the rad. When i take rad off and open valve the water comes out hot. Any ideas?

 

[GasSafeTony]

Its possibly air locked...Close all other radiators off and leave the one not getting warm open....see if you have any joy.

Cheers I will try this tomorrow and let you know how i get on.

Also, if it not a combi boiler and there's an indirect cylinder (copper tank in airing cupboard), make sure you close the gate valve on the return pipe to help force the air lock out (that's if it is an air lock).

Tried this last night as this is really frustrating me. All rads shut off with only the one that does not heat up left on and it will still not heat up. lifted floor boards up and from the boiler we have 22mm pipe which travels about 6-7 feet away from boiler then it reduces to 15mm. With all rads off and only the problem one on, the pipes under floor boards were just heating up to where they reduce to 15mm. All the rads tee off from the 15mm pipe-work and travel horizontal for a few inches and then 90 degrees down to the rads. The rad that is not working tees off horizontal for about 8 inches then 90 degrees horizontal for 4 inches then 90 degrees vertical down to the rad. When i take rad off and open valve the water comes out hot. Any ideas?

It sounds to me like the pipe work is blocked, water will still come out even if it's blocked for a few minutes as its either under pressure (combi boiler) and has a leg of water. I'd remove rad, and draw off at least a bucke of water from each pipe to eliminate a blockage.

 

[swbjackson]

Has this radiator ever worked? I've had this a few times after changing a dead boiler and when you question the customer you discover the radiator has never worked properly. If it's never worked both pipes could be connected to the flow or return instead of the flow and return, particularly as you say you get a good flow out of both valves.

 

[gsandi]

Has this radiator ever worked? I've had this a few times after changing a dead boiler and when you question the customer you discover the radiator has never worked properly. If it's never worked both pipes could be connected to the flow or return instead of the flow and return, particularly as you say you get a good flow out of both valves.

Cheers, we have only had the house two months. I am going to try and extend the 22mm line to increase flow rate. this will have to wait until weekend.