One luke warm radiator - need help tried everything! open vented gravity fed central heating

[marc1977]

Hi,

Need some help with a radiator in a bedroom that does not get above luke warm. I have fiited a new 6 metre pump, the water pressure is good and flows well from both inlet and outlet valves. Today I fiited a new radiator as (following a plumber who came outs advise) the old one may have been corroded and therefore causing a blockage - but still no change! What can this be? the inlet valve is really hot but the water is clearly not flowing through the radiator well. I flushed the system and let both valves run for a long while to clear out any blockage and they run fine???

Is a 5 bed house with standard open vented gravity fed central heating

Thanks

Marc

 

[dontknowitall]

Could be a fault with the TRV or maybe the lockshield isn't open enough - I assume it's bled properly?

 

[justlead1]

Turn every rad off, and both valves on new one, remove plug at top of rad screw in a 1/2" fitting so a bowl/bucket can catch water. Bucket ready turn on on vale on rad purge for say 20 seconds. Turn off valve and repeat with other one. turn off refit plug. Turn on both valves and boiler/pump check results. If OK turn on the rest and balance system if needed. Good Luck

 

[marc1977]

Thanks, unfortuntely I had a plumber in who tried the above with the old radiator. He said all looked fine - no blockages and a good pressure. he thought it must be the radiator at fault which is why i fitted a new one. Now im thinking the pipework must be bad or something.

 

[marc1977]

mind you he didnt try it with all the other rads switched off.....

 

[fuzzy]

usually the trv

 

[WHPES]

I assume the system is properly balanced................

 

[fuzzy]

probably no WHPES, but still usually the trv, even badly balanced systems usually get round

 

[villa_tom]

I would definately try it with all rads turned off if he didn't. Then if that fails I would go with the TRV. Have you tried taking the head off the TRV as the pin may be stuck down slightly??

 

[fuzzy]

cannot believe that the plumber suggested it was the rad!!!!!!

 

[villa_tom]

cannot believe that the plumber suggested it was the rad!!!!!!

I think he could smell a few quid in it for himself, atleast the blokes done it himself now and not got stung for labour costs

 

[fuzzy]

mmm true, but still bought a rad he didnt need too

 

[metaldust9]

its not fed off 10mm ie piggybacked of the same pipework as nearest rad, so not enough flow,plus turn off all the rads upstairs at the valves.

 

[justlead1]

Plumbers only a word Fuzzy

 

[Avatar]

yeah - the odds on a corroded rad, and not something else is a few thousand to one!

 

[marc1977]

So...firstly there are no trvs fiited to the radiators Im afraid. I did as suggested and piping hot water bellowed out of the open radiator plug when both inlet and outlet valves were opened. However now it is all plumbed in the radiator is cool again! The system is been balanced too.

This is driving me nts and im already £100 down on a pump, £130 down on 2 hours of useless advice from a plumber and £80 down on a new double radiator!!!

any futher suggestions welcomed ....

 

[fuzzy]

does water run from each valave or just coming from one?

 

[marc1977]

Hot water is running from BOTH valves

 

[PlumbBobBob]

i could be wrong but sounds like both pipes are feed? where do they connect to.

 

[marc1977]

no idea, its all under the flooring! how can I tell apart from lifting up the floor boards?

 

[marc1977]

Also one valve gets really hot but the other remains cold when in operation (i.e there is no flow)

 

[Avatar]

Back to square one i think - was the rad working in the past or has it always been like this, and for how long? Was there ANY work done on either this rad, or the heating system that coincided with the rad not heating up?

These questions are fundamental to any further gesticulation on my part . . .

 

[dhgas]

Check that one of the rad valves does not have a loose jumper that acts as a non return valve, had this once and took ages to find, as water flowed quite happily from both valves with the rad off.

 

[marc1977]

Ive just moved in so dont know for certain if it ever worked. However it looks as though the plumbing was put in with the side extension around 20 years ago so I cant beleive it has never worked!

The radiator just has bog standard valves fitted so I dont think these have jumpers???

 

[obseen16]

Ive just moved in so dont know for certain if it ever worked. However it looks as though the plumbing was put in with the side extension around 20 years ago so I cant beleive it has never worked!

The radiator just has bog standard valves fitted so I dont think these have jumpers???

this sounds exactly like a job i did a few weeks ago, customer complained that upstairs rad didnt get hot in the kids room. took a look. fiddled about with valves etc, after a while of noggin scratching she mentioned the bloke who lived there before her had been a bit of a diy enthusiast. they had a ten year old extention which was right below and to the side of the problem rad, it had a monster rad in it something like 2000 x 700 k2 it was a beast, he had done all his own plumbing work, lifted the boards upstairs and found that he had plumbed upstairs rad to the flow on both ends and the beast rad downstairs was teed off one of the upstairs tails and then teed into the return which was right next to the flow, the diy guy must have been a right pebble or something rest of the house was 2 pipe configuration. anyway re jigged the pipes under the floor and all was well with the world again.