cold rad

bideye

hi

can anyone help cant afford a plumber - all the rads in house are working except one which remains cold , pipe into rad on one side is hot but nothing happening with the rad:(

sullzz

have you got a trv fitted at this rad on the pipe that is hot , the reason im asking this is because sometimes if you have a trv turned off for a period of time , lets say over summer , and then in winter you want this rad turned back on , you open the trv and the pin had become stuck , if this is your problem what you can try is .... remove the trv head and with a spanner or similar tool tap the body of the valve and you should see the pin rise out of the body of the valve , this should let the heat into the rad . also check the trv head is working by turning it upside down and open it and close it ensuring that the inner body goes in and out.

Now if you dont have a trv fitted on this rad it is possibly just an airlock it should not need balancing if it worked before , what you need to do is shut all the other rads in the house this will cause the water in your system to circulate only through this rad and your cylinder causin the airlock to clear .
good luck,
sullzz

danjo-xx

bideye wrote: »

hi

can anyone help cant afford a plumber - all the rads in house are working except one which remains cold , pipe into rad on one side is hot but nothing happening with the rad:(

May seem stupid but is the valve at the hot pipe, 'open' and where exactly is this rad, is it the last in line? is the system very old as I recently had the same problem, it was the last in line, warm pipe but no radiator heat, turned out the rad had to be rodded to clear it out, got it done during an upgrade of controls.

cbreeze

try also bleeding the rad with a key, plus the other suggestions

bideye

yeah think its last in the line, gonna try turning off others see will it work

thanks

AckwelFoley

even if its the last in line there should be some heat

It needs to be beld if:

Part of the rad is cold in patches, usually the top, and there is good heat in the bottom. It the entire rad is cold, top and bottom, its unlikely to be airlocked.


Failing that - there are 2 valves on the rad, one if a flow valve, and one is a "one off valve" The former (bottom in pic) is for controlling the flow of water into the rad, the other is like a tap for turning it on and off. This cap pulls off and can be adjusted with a special key (or a pliers)

The flow valve is the valve that doesnt have a screw cap on it, there may be a plastic cap on it but it is only a cover it wont twist the valve, the other valve (top in pic) has a cap on it, which has a screw in the top if it to connect it to the valve in order for you to turn it on.

First turn the "on off" valve anti clockwise until it stops, wait and see if there is any heat beginning to fill the rad - if that doesnt work adjust the flow valve, it may have been mistakenly adjusted previously, turn this with a pliers anti clockwise also, open it fully. When they are both wait 15 mins or so, you will need the heat on obviously, then bleed the rad.

Failing all of the above. there may be a more serious air lock, but i doubt it