Cold Radiators

DC2Z

DC2Z

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Can anyone on here help, I have 2 radiators in the house that don't seem to work when all the others do.
Each Radiator has its own thermostat.
The 2 radiators aren't next to each other. One is in the dining room (Back of the house) the other is in and upstairs front bedroom.

Any ideas?

:help:
 
Drained out any air from the top?
 
Is the feeder pipe to the two radiators hot?
If so then get a radiator key (if you don't have one) and bleed the radiators until you see water coming out.
Turn the key slowly as you don't want a massive gush :)
 
And dont break it off.
 
If the radiators are already full of water but not getting hot then it's possible you may have an airlock somewhere along the pipes that feed the radiators. One way to free the airlock is to put your heating on and turn it up full to build up some pressure then release some water out of the cold radiators which should cause the hot water to force its way through. The blocked air will then make it's way in to the radiator so you can bleed it out as normal.
 
As above, but if none of that works.....

When the radiators have been off for a while, the valve somtimes sticks.

Whip off the thermostat, and your left with a "pin" sticking out of the valve, grab a hold of this with a pair of pliers and pull it out,BUT NOT ALL THE WAY OUT,and work it in and out a few times or until the spring inside keeps it out, then re-fit the thermostat and it should work.
 
excellent cheers I shall try some of these ideas.
 
The radiator in the dining room, the two pipes going into it aren't hot
 
DC2Z said:
The radiator in the dining room, the two pipes going into it aren't hot
Click to expand...

It could still be an air lock in that part of the system.
 
Yes.
If water comes out as soon as you open the valve then it won't be blocked.
If you hear a hissing then wait for the air lock to clear and the water runs through the valve.
I presume the inlet pipe on the radiator upstairs is warm?
Where is your boiler located?
If it's upstairs then these radiators will be fed first and vice versa if it it downstairs.
 
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Water came out pretty much straight away. (Cold) It sounds like the radiators are trying to do something. The top of the pipe is hot

Boiler is located in the kitchen next to dining room
 
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Sounds like it could be a sludge/air lock problem, you could try shutting down all other rads in the house leaving just one of the problem ones fully open then turn on heating full that should clear any air/ sludge from that radiator, then repeat the process for the other rad.:thumbs:
 
If it's a traditional boiler system, make sure the pump is working too. If it wasn't running, radiators above the boiler may still heat up due to gravitational circulation but those to the side would not.

Most pumps have a chrome screw in the end. If this is removed it reveals the end of the motor shaft which can be turned with a large flat screwdriver. Often just a quick turn will get it going again.


Steve.
 
I had this problem once, it was the stat on the radiator !

I hit it fairly hard with the adjustable end of a large adjustable spanner and I've never had a problem with it since !
 
Borats Baby said:
I had this problem once, it was the stat on the radiator !

I hit it fairly hard with the adjustable end of a large adjustable spanner and I've never had a problem with it since !
Click to expand...

:lol:

Thats what i tried before taking the thermostat off, It worked for one, but not for the other 2.:D
 
I'd go with removing the thermostat head and checking the pin moves. Maybe check the valve the other end of the radiator is open too. that one should be a simple square tap shaft after you pull the cover off. Just check it is unscrewed as far as it goes (you may need to close it again a bit if the rad starts to works too well and other rads don't get hot enough)
 
try very carefully to tighten it after giving it a good soaking with WD40 or similar and then undo , it might sound daft but give it a go :)
 
But whatever you do, DO NOT under any circumstances let B Gas
fit a Magna Clean filter.
Was told by the service engineer :lol: This would stop a build up of sludge in my system :rules: What utter twaddle , didn't stop leaking even after two visits ,so told em to stuff it,
Got a letter from them saying " as a gesture of good will , B Gas will not charge you for appliance or labour charges" :bang:
What Bl##dy cheek :bat:
 
towershot said:
But whatever you do, DO NOT under any circumstances let B Gas
fit a Magna Clean filter.
Was told by the service engineer :lol: This would stop a build up of sludge in my system :rules: What utter twaddle , didn't stop leaking even after two visits ,so told em to stuff it,
Got a letter from them saying " as a gesture of good will , B Gas will not charge you for appliance or labour charges" :bang:
What Bl##dy cheek :bat:
Click to expand...

Whilst that was your experience, ours was totally different. We had a magna clean fitted by the British Gas engineers after a power flush on our 25 year old system and it does what it says on the tin. The system is much improved and dry as a bone.

Anthony.

PS. and the magna clean is cleaned on each service - always a deal of crud on it too...
 
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towershot said:
They tried a couple Anthony, each leaked ,the first time into my shoes which I keep there.
Second time into a cup because He was SURE this one was one of the GOOD ones.....:eek::suspect:
Click to expand...

Sorry to hear that.

We had an additional radiator fitted (not by British Gas) many years ago. My wife wanted to put dust sheets under where the guys were working "in case it leaked". Cue sneering workman mode for the 'little woman'. Radiator fitted and yes, of course pinhole leak which pee'd rusty water onto off-white carpet. Exit red faced workmen after fitting a replacement.

So you do have my sympathy.

Anthony.
 
towershot said:
But whatever you do, DO NOT under any circumstances let B Gas fit a Magna Clean filter.
Click to expand...

I wouldn't get them to fit a central heating system either. They will charge more than most and will not make any effort to hide pipes. Everything will be run on the surface of the walls up to the ceiling space by the most convenient route possible.


Steve.
 
Agree with above comment british gas do not hide pipes and are 3 three times the price.
 
Steve Smith said:
I wouldn't get them to fit a central heating system either. They will charge more than most and will not make any effort to hide pipes. Everything will be run on the surface of the walls up to the ceiling space by the most convenient route possible.


Steve.
Click to expand...

I wouldn't get British Gas to change a tap washer !
 
Anyone got a suggestion for freeing up bleed valves? Blowlamp for 30 seconds.
 
Hi,
Not sure how things are going but do a lot of repair work on rads and this is how I would det about it.
Check that the lock shield valve [opposite end to thermostatic valve] is at least partly on. You will need a pair of grips or pliers as the valve knob is designed not to move it!
If thats on, take off the valve head at the other end and check that the pin in the valve is 'up'. It should be posible to push it in with a pair of pliers. If its stuck down give it a gentle wriggle with pliers/ tap side of valve body.
Assming thats ok turn off the other rads so only this one is on. Get yourself a bucketand a large towel. Whip out the bleed valve and let it run for 5 mins, you may get a lot of air in fits and starts just keep the bucket there! If the water runs hot it means that its coming in one end of the rad at least. Put the bleed valve back in and see if the rad/pipes heat up.
If it doesn't it could be either a faulty therm/stat valve or the rad could be blocked...

Let me know!

Cheers,

Dunc
 
retired said:
Anyone got a suggestion for freeing up bleed valves? Blowlamp for 30 seconds.
Click to expand...

hammer.jpg


+

biceps.jpg
 
Duncan.F said:
Hi,
Not sure how things are going but do a lot of repair work on rads and this is how I would det about it.
Check that the lock shield valve [opposite end to thermostatic valve] is at least partly on. You will need a pair of grips or pliers as the valve knob is designed not to move it!
If thats on, take off the valve head at the other end and check that the pin in the valve is 'up'. It should be posible to push it in with a pair of pliers. If its stuck down give it a gentle wriggle with pliers/ tap side of valve body.
Assming thats ok turn off the other rads so only this one is on. Get yourself a bucketand a large towel. Whip out the bleed valve and let it run for 5 mins, you may get a lot of air in fits and starts just keep the bucket there! If the water runs hot it means that its coming in one end of the rad at least. Put the bleed valve back in and see if the rad/pipes heat up.
If it doesn't it could be either a faulty therm/stat valve or the rad could be blocked...

Let me know!

Cheers,

Dunc
Click to expand...

Thanks for that, I'll be working on them tomorrow so I shall let you know
 
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