radiator cold at bottom and hot at the top

[bubblefish]

Hi, i am looking for a bit of advice.. all my radiators are ok except for the one in the living room.. its hot at both entry/exit points (whichever one is which) to approximately 1 foot away at which point it goes cold.. its hot all the way across at the top. i have bled all the radiators which has had no effect.. i was wondering if it could be a pressure problem as it is the biggest radiator in the house (about 5x2.5 ft). i am on a kitchen mounted halstsead best 40 boiler with a 3 port valve in the airing cupboard next to the storage tank, i believe its an open system as i have no pressure gauge. the thing thats puzzling me is i have a tap between the pump and the cylinder at which i have tried in different positions and does not seem to make a difference. any help you guys could give e would be appreciated... javascript:emoticon('')
Confused

regards alan

 

[bster]

is there a thermostatic valve on the problem rad?

might be sludged up though, how old is the radiator?

 

[bubblefish]

it has a small rectangular type key on either end which are fully open, but no thermostatic valve..

alan..

 

[bster]

try turning off all or some radiators and see if the problem rad starts working. (turn off your hot water as well).

 

[uug197h]

Hi Your rads need a power flush this will cost about £425 for a 7 rad system

 

[jumbo55]

cold at bottom hot at top, usually sludged up, sludging usually happens on ground floor rads. incoming and exiting valves hot, no problem there. hot at top therefore not air. you could try a desludger from your plumbers merchants, follow the instructions carefully, you could try isolating the valves, take rad into garden and running pressured water through the offending rad, but the best thing of all is to get a powerflush done by a reputable firm. this is a chemical pressure clean, and should sort the problem out, make sure you fill the system with inhibitor afterwards.

 

[bathjobby]

If its only the 1 rad just take it into the garden and flush it through with garden hose. Whilst you have it off, open the valves one at a time (with container underneath) just to let any sludge out of them also. Doing anything else with the rad in situ will just move the sludge into solution and the rest of the system.

 

[bubblefish]

thanx for the advice all.. i will take it off at the weekend and give it a blast with the hosepipe and see if it makes a difference.. with me being on an open system am i right in thinking that the system will fill back up once i have
put the radiator back on..

regards alan

 

[bster]

when you flush the rad out bang it with a rubber mallet or something similar to dislodge stubborn scum!

 

[bathjobby]

with me being on an open system am i right in thinking that the system will fill back up once i have put the radiator back on..

Yes, you just need to bleed to air out of the rad the get the water back in.
N.B. after you have turned both rad valves shut before removing the rad, put a tray under each one as sometimes (particularly on older valves) they drip a little even when closed. Plus, the sludge that is in your rad WILL stain anything so be very careful when removing i.e. trays under each valve, sufficient to hold all the water / sludge out of the rad. Carpets will be ruined if you get this stuff on them....

 

[bubblefish]

Thanx for all your comments guys.. tookoff radiator last weekend and flushed it through.. was amazed at the black sludge that came out. (made a right mess of the front lawn.. (better than on the carpet though ))... its now as hot as hell all over.. thanx once again guys..

 

[croydoncorgi]

don't forget to add inhibitor to prevent it all happening again!

 

[iamthebestuk]

don't forget to add inhibitor to prevent it all happening again!

Hi, I'm experiencing the same problem of hot at the top and cooler at the bottom, only my radiator is brand new and I've had the problem since it was installed.