Wits end with rad not working!

[texasjim]

Hi guys. I wonder if I could get some advice here. I live in a semi detached chalet bungalow with nine radiators, three upstairs and six downstairs and an oil fired boiler. I'm currently changing to an a rated condensing boiler but have a problem with one of the radiators downstairs. I've tried everything but it won't heat. 1, I've turned off all the other radiators in the house, turned up the thermostat and it simply didn't make a difference. 2, I've taken off the radiator, took it outside and flushed it out and it seemed fine. 3, I thought it might have been the lock shield valves so when the radiator was off I turned the flow on and put a basin underneath the valve and there is a good flow. 4, I put the radiator back on, bled the radiator but it simply won't heat. What I do notice is that the flow pipe from the floor into the radiator is hot but the return is not and I don't have heat in the radiator whatsoever. Spoke to a plumber and he seems to think it might be something to do with e pipework but I don't understand how it could be the pipework when the inlet flow is hot, thanks in advance,,jim

 

[Simon F]

has it ever worked?

 

[texasjim]

No not really. At best Luke warm

 

[scotty plumber]

If both valves are working fine i would say that you need to invest in a new rad!

 

[SimonJohns]

I would try the
Taking rad off and running water through valves again

Did you run both valves?

 

[Simon F]

can you get access to the pipes to see how they are configured?

 

[desrob]

n the return try to encourage them to cyclethe return and open the rad at return end to encourage the hot water through,then do the same oo

 

[texasjim]

Yes checked both valves and they ok. Can't get access to pipework cause solid oak floor on top of concrete floor. So I've no idea of pipework configuration. Even tho I flushed rad, do u think it could still be the rad?

 

[desrob]

Yes checked both valves and they ok. Can't get access to pipework cause solid oak floor on top of concrete floor. So I've no idea of pipework configuration. Even tho I flushed rad, do u think it could still be the rad?

....no......

 

[texasjim]

Sorry des I'm unsure what u mean?

 

[scotty plumber]

I have replaced many rads that have decided not to heat up

 

[texasjim]

Do u think it could be a balancing problem?

 

[PlumbBobBob]

no because you said you closed all the other rads off and it still didn't work

 

[Mr Flux]

has 2 be a air lock in the return! connect the mains up2 the system and open the return rad valve should release any air in that section of pipework! Or you can take a piece of flexy pipe of the mains filling the tank and shove the haf inch flexy down the cold feed from the f&e and give it a blast, bear in mind ya need 2 people to do this 1 to open the valve downstairs and 1 to make sure the f&e dosnt overflow!

 

[Best]

You really should have joined a pipe & hose to each valve in turn, & let the water flow out for a good 60sec or so, to eliminate the possibility of pipe blockage or air lock, because there may be flow of water before it nearly stops or air comes out. Mr flux idea of putting mains through pipes is only a last resort & risky to a novice, but often needed.
Be careful you don't have a faulty motorised valve which is permanately almost off, but not quite, like I came across 2 weeks ago! In my case it was the last rad in system wouldn't hardly heat at all & the flow pipe was hot. Discovered a motorised valve below a bedroom floor was to blame.

 

[Best]

Obviously watch Trv is working ok & on correct pipe.

But one thing that can happen, & I will guarantee would fool the best, most experienced guys, is a faulty wheel head or lock shield valve that is fitted on the return side of rad. The water will flow out of each valve when opened, but no heat will pass the return valve.
Any ideas guys?
The brass seal ( washer if you like ) is detached from works inside valve, so only will let water flow one direction, so no good on return. Seen this very rarely.

 

[Paulus]

Perhaps a simpler way of establishing where the problem lies would be to turn off both rad valves, bypass the rad by fitting some plasic pipe between the two valves and turning them both on again. If the circulation through the pipe is okay it would indicate that the rad is the problem. If the circulation isn't okay more investigation of pipework and motorised valve needs conducting.

Good luck.

 

[Best]

Perhaps a simpler way of establishing where the problem lies would be to turn off both rad valves, bypass the rad by fitting some plasic pipe between the two valves and turning them both on again. If the circulation through the pipe is okay it would indicate that the rad is the problem. If the circulation isn't okay more investigation of pipework and motorised valve needs conducting.


Good luck.

I have thought on that, but the only trouble with that idea is if the flow is just passing through one of the pipes that is blocked, like even a pin hole opening, the pipe you join will heat up, but this very slight flow would be lost into the rad, & it would lose the heat.

 

[texasjim]

Thanks guys for all your advice. ive just finished block of shifts and will have a go again taking aboard all ur advice. thanks again much appreciated.... jim