Radiator driving me to madness...

[Ransom12]

Hi all,

We recently moved into a new property which was built in 1995. So the boiler and radiators are approx 20 years old I can only assume at this point.

I had the main bedroom walls re-skimmed and had to remove the radiators. When putting them back on I tipped one side of the radiator and black sludge poured out of them! However this radiator actually work no issues as does the other in the same room which did not get emptied...

There is also a magnacleanse fitted which I have just checked and it had a very low amount of build up but it is still magnetized.

I do not really understand all the terminology but I will explain the boiler setup.

Boiler downstairs.
Airing cupboard upstairs with magnaclean and a tank which looks to be HW storage / immersion heater.

The issue I am having is that all the upstairs radiators are piping hot, while the downstairs is luke warm or cold. They change from being hot or cold and this is with the system on and thermostat set to 30c... As the upstairs is piping hot, i can assume this is not the boiler at fault.

The pump which is upstairs in the airing cupboard is set to a relatively low setting and all radiators in the house are set to fully open.

I have read around 30 other threads on here of others having issues but not really sure where to start.

On a final note, sometimes the radiators downstairs get hot but this again is randomly happening..

All Radiators have been bled and I do not think I have any air locks.

Any advice on how to move forward fixing or diagnosing this issue would be really appreciated.

Happy weekend all!

PS> I am at work but can provide pictures of anything if that would help.

 

[Burnerman]

Have you read the FAQs on radiator balancing? This involves closing the lock shield valves a bit, hence forcing the hot water around the heating circuit.
The black sludge is magnetite (rust, effectively) and it's always lurking to some degree.
John

 

[Ransom12]

Hi John - Yes I read the guide literally just now and will be closing all the upstairs radiators to see if this turns all the downstairs on. Then I will know if it is a blockage or air lock. That is my understanding at the moment and plan.

I will upload a picture of my pump as I am sure it is not set high enough for the system when I get home in a bit.

Thanks for your response.

 

[Burnerman]

Good luck with it mate.....often enough the lock shields only need to be open one turn from off - sometimes slightly less.
John

 

[Ransom12]

OK so last night I checked all my radiators again. Now all of them are hot ... So I really have no idea what is going on. I think there must have been a blockage or air block that has passed, perhaps my persistent bleeding of the system has paid off.

This forum has been a great resource as I have now discovered that all my radiators are cold from the bottom middle, to about three quarters the way up the radiator, in a triangular shape from the entry > exit point.

So my next plan is to get the whole system flushed right?

Also my pump seems to be on a low setting from what I can gather, which might explain why my magnacleanse is not really catching much of the iron sludge or is this because it was introduced after the problem had already built up in each radiator?