Air build up in radiators

[firebladerrw]

I have an open vented system, with boiler downstairs, pump in airing cupboard upstairs, and usual expansion talk in the attic. 12 radiators in total.

I've noticed that 2 radiators upstairs need bleeding every few days, and wonder where or how air is getting into the system? All other radiators are fine.

Anyone got an idea?

Thanks

 

[corgiman]

probably not air but hydrogen

you may have iron oxide (sludge) build up in the system, is the water from the rads discoloured?

 

[firebladerrw]

probably not air but hydrogen

you may have iron oxide (sludge) build up in the system, is the water from the rads discoloured?

Thanks

No - I've used sludge remover twice on system (going to fit new boiler soon), and its always had inhibitor.

When I drained the system, the water was very clean, and quite frothy - inhibitor obviously working.

Edit: I also have a Magnaclean on the system.

 

[corgiman]

is the magaclean clean?

 

[firebladerrw]

is the magaclean clean?

Only fitted few days ago, and haven't checked it - yet !

 

[corgiman]

have a check

have you flush the x400 out yet

when did you put it in?

 

[firebladerrw]

Checked it just now - it was heaving with sludge ! Cleaned and put it back in system ! Sludge remover was put in system 3 days ago.

Despite the clean looking water, it looks likely that there is still a fair amount of iron oxide circulating in the system !

Incidentally, despite all the negative comments on Magnaclean in here, my experience so far is 100% positive - easy to fit, no leaks, opened cleaned and system back running in 7 minutes !

 

[corgiman]

You have a shed load of sludge and thats producing hydrogen and
3 days is not enough keep it in for at least three weeks before flushing out.

Dont add ihibiter untill you have flushed it out and keep cleaning out the magnet periodically

good luck

i have no opinion on the magnaclean really it does what is does

 

[firebladerrw]

Great advice - thanks.

Intended to leave it in for a few weeks. This is all part of my scheme, in preps for new condensing boiler, which id hope to have fitted in around 6 weeks. Just trying to get the system as clean as possible. Next on the agenda is flushing the radiators.

 

[JohnD]

while you have a Magnaclean and X400 circulating, it is useful to turn off all the rads except one, open the valves at both ends of that one, turn up the pump (unless you get pumping-over) and get a strong flow through that single rad. Then turn it off and repeat on the next until you have done them all. You will have to re-balance the lockshields afterwards.

In this hot weather you can turn down the boiler stat to save wasting gas.

I am a householder not a pro.

Isn't it satisying to scrape all that sludge off the magnet sheath?