radiator cold at bottom

[foxboy]

The system is running off a Worcester 24cdi which works fine without any unusual noises and plenty of hot water. All the rads are hot upstairs and also the one at the bottom of the stairs, however, the large rad in the lounge is very hot from midway up and warm/hottish across the bottom. I have taken it outside and flushed it with a hosepipe although the water ran clear. I have also changed the thermostat - no different. Today I turned all the other rads off, but it stayed the same.
Any ideas guys

 

[cozzmic]

How big is the rad,is it a double panel and what size are the pipes going to it

 

[billozz]

has the rad always been like this or has it just changed

 

[foxboy]

It's a double panel rad with 10mm feed. I don't know when the change happened as it was in a house I've had rented out and just got back.

 

[kevplumb]

It's a double panel rad with 10mm feed. I don't know when the change happened as it was in a house I've had rented out and just got back.

self explanitory then

 

[foxboy]

Please explain Kev for the uninitiated such as myself..

 

[kevplumb]

flowrate old son it's not enough that's why its cold ish at the bottom

 

[foxboy]

Cheers Kev. Is there anything I can do to improve it?

 

[kevplumb]

see if the locksheild is fully open or change the pipe

 

[foxboy]

Yeah the lockshield is fully open and the feed pipe is red hot. It's also the last rad to get up to temperature which again supports your theory. Don't much fancy putting bigger pipes in though, so I guess I'll just hope for an early summer
Thanks again Kev

 

[croydoncorgi]

You could try reducing the flow through some of the other rads by closing the lockshield valves a bit. If the feeds to the big rad really are 10mm, you'll probably have a problem getting much more flow through them but it's worth a try. Also, you may make the pipes noisy by forcing too much water through a small diameter.