One radiator not heating up

[Harry Bloomfield]

No good trying to flush one rad insitu, it needs to be taken off and done in isolation in the garden. Easy enough DIY as long as your isolating valves work and you can lift/remove the rad( extra hands make it easier) Hopefully should be some info on Utube. Good luck

If it wasn't circulating well from first install, and has deteriorated since then - it suggests to me that the whole system needs a good flush out.

 

[Harry Bloomfield]

Sometimes that is because all the sludge and sediment has settled to the bottom of the pipes, radiators and boiler.

I've drained and flushed maybe twice, thoroughly, never seen anything to concern me at all. The filter collects nothing, my system works good as new, so why would I use X400?

 

[JohnD]

If you wanted to dislodge resident sludge and sediment that is undisturbed by plain water.

 

[Dereekoo]

If it wasn't circulating well from first install, and has deteriorated since then - it suggests to me that the whole system needs a good flush out.

OP just infers problem with just one radiator? If its not broke don't try and mend it.

 

[Harry Bloomfield]

OP just infers problem with just one radiator? If its not broke don't try and mend it.

The OP's symptoms could suggest either blocked pipes or choked radiator. The dirty water coming out of the radiator suggest that is typical of the entire system, so were it me, I would give the whole system a good flush out. Why do half a job?

 

[Ashgvas]

I was referring to it needing a powerflush now, so soon after original installation was completed - assuming it has had inhibitor put it, as it should. My own system is 40 years since it was installed - drain my system and what comes out is completely clear.

We have put an inhibitor as well. Was put when instalation was done. But I have seen the liquid coming out is dark brown in colour. Probably the new radiators needed a flush when installed and it wasn't done? Also does it make a difference that they are cast iron? Do they sludge quicker?

 

[Dereekoo]

The OP's symptoms could suggest either blocked pipes or choked radiator. The dirty water coming out of the radiator suggest that is typical of the entire system, so were it me, I would give the whole system a good flush out. Why do half a job?

Flushing out one rad out as opposed to flushing all rads and pipework is certainly less than half a job (time) and may well sort out the immediate problem, OP can then decide how far down the line he wants to go, full flush, magnaclean, etc etc

 

[Harry Bloomfield]

We have put an inhibitor as well. Was put when instalation was done.

I would suggest it's rather pointless putting inhibitor into an already dirty system.

But I have seen the liquid coming out is dark brown in colour. ProYou bably the new radiators needed a flush when installed and it wasn't done?

A previous post in the thread(?), suggests that after any major work on your system, it ought to have been given a hot and cold flush out. I agree it ought to have been done, but it seems it wasn't.

The dark water, plus rad not working, adds up to a system already partially choked up - Which really, is why if it were my system, I would want to give it a good flush out myself now and add a filter in the return to the boiler. You obviously have circulation problems now, why mess about with partial fixes.

Also does it make a difference that they are cast iron? Do they sludge quicker?

Best refer that question to those with experience of both, but I would guess there should be little difference.

 

[Ashgvas]

Flushing out one rad out as opposed to flushing all rads and pipework is certainly less than half a job (time) and may well sort out the immediate problem, OP can then decide how far down the line he wants to go, full flush, magnaclean, etc etc

What's Magnaclean? Is it a sort of inhibitor?

 

[terryplumb]

It's a magnetic filter ,installed on the central heating pipework.

 

[Ashgvas]

It's a magnetic filter ,installed on the central heating pipework.

Thanks. I presume it helps to avoid build up of further sludge after a powerflush?

 

[Old Salt]

Why not just change that radiator? certainly cheaper than an £800 flush

 

[terryplumb]

Thanks. I presume it helps to avoid build up of further sludge after a powerflush?

It collects magnetite as it passes through the filter, and if installed in the first instance, helps prevent blockages forming.

 

[terryplumb]

Is the problem rad one of the original 9 ?? Did it ever work fully ?

 

[old duffer]

its nothing to do with rust in the pipes, it's a water pressure differential issue which is stopping flow.
Each emitter needs to have a differential across the in/out or flow will not occur. The differential can be very small.
If it is indeed the last in the circuit, you can prove the pressure differential by closing off the a few of the rads. This will force flow and prove the point. Then the balancing is done from this rad. So close all rads and leave this one open, put heating onto full blast. Then start working back towards the boiler in order sequence and keep checking back at the problem rad to make sure its still getting flow.