cold radiators down stairs. was only 1 now 2 following flush

[nenevall]

system is open vented, 3 rads, 1 downstairs very close to the boiler, 2 also down stairs, none upstairs.

problems started with 1 rad down stairs stone cold, other two are red hot.
bled problem rad and got hot water coming from the bleed point, but rad refused to go hot

I suspected sludge in the rad, so drained down the system, and shut the boiler down and isolated cold water feed.

removed rad and flushed out loads of gunk........

reinstalled rad and put in sludge remover into header tank in loft while system was drained down....

turned on header tank water and allowed to fill.

started boiler, got hot waterout of taps so i know the boiler is producing the hot water!! The one rad downstairs near the boiler is hot the other two down stairs which are fed by pipes going up through the loft are now cold.

Suspect pump, took pump apart, impellor is spinning, okay and stops spinning when turned off.

bled all 3 rads, the 2 downstairs are now clear of air and the cold water bleeding from them smells like the sludge inhibitor smell. (like a citric smell)

the one down stairs close to the boiler when bled produced hot water!

----

3 hours in and still the 2 down stairs are stone cold.

any suggestions.... i`m really loosing the will to live now!

 

[Aquilani]

Put heating on only, isolate the rad that is working and try. Is the pump pulsating? Try venting it with the two that are not working on alone.

Also do they have Thermostatic Valves on the radiators? These could be stuck.

 

[45yearsagasman]

You're losing the will to live, well so am I after reading such a confusing ramble. Either you have rads upstairs or you dont, make up your mind.
Now back to Strictly.

 

[nenevall]

okay sorry about the slightly confusing ramble!

all rads are downstairs, ie on the same level as the boiler and CH pump, however the pipes feeding them go up into the 1st floor before going back down to the ground floor.

there are no rads installed upstairs, there are pipes there in the other rooms upstairs should we ever wanted to install rad`s in those rooms.

there are no TRV`s, all rads are simple on/off valves.

we have isolated the good rad via its valves but this has made no difference to the other 2 cold rads.

 

[JohnD]

you say you have a total of 3 rads in the house, and you have turned off the only one that was hot, but the other two are still cold, is that right?

is the cylinder unusually hot?

is the boiler and the pump still running?

what temp is your room stat set to?

which chemical are you using?

when you bled the rads, what came out?

 

[PowerFlushAssociation]

Fundamentals:
Putting in sludge remover does not make the sludge disappear only breaks it down in smaller pieces and makes loads that were stuck on the inside walls (out of the way) fall off and start circulating around (now in the way)
Sludge remover will have to be flushes out / drained out of the system, before you add inhibitor.
Sludge remover should not be left in systems for more than manufacturers recommend (4 weeks normally)
Inhibitor does make sludge hard and sometimes cake together, so unless the system is clean it can actually causes trouble. But you should always have inhibitor in anyway.
Draining the system does not really clean out the sludge, just some, and only the lightest smallest pieces.

What happened?
More sludge have fallen off the inside walls making the sludge problem worse. All this sludge in now moving around the system and has blocked the flow to the other radiators.

You, really need a power flush.

 

[dave18]

I would say that you have an air lock,

You say that you drained the system that has pipes going from boiler on G/F
across loft and down to rads on G/F so pipes form an upside down "U" bleed pipework in loft where air is trapped and all should be ok.

You can then cancel the undertaker.

David

 

[nenevall]

Ok here's the low down.

Power flush carried out yesterday, 6 hours later and magnet filters were totally clogged, indicating a effective powerflush.

Also had the grundfos 15/50 replaced as the impeller was clogged and corroded.

End result is the whole system is certainly better and all rads are hot through out. Heat up time is now minutes... Not hours <> days.


So here's the question... Whilst fitting the magnaclean filter in the 22mm boiler return pipe, we found it was still full of magnite. Using a magnet to test for it we found the main return pipe could keep the magnet attached!

So what's the best way to work the remaining magnite out of the 22mm pipes? Bearing in mind the powerflush couldn't shift it...

24hrs on the magnaclean has caught some light magnite but not as much as I suspect is still in the main 22mm pipes.

 

[JohnD]

are you in a hard water area?

do you know what chemical was used during the powerflush?

is your an open-vented system with a feed and expansion tank in the loft?

 

[nenevall]

Soft water

X800 superflo

Open vented

 

[JohnD]

well X800 and a powerflush should have got it pretty clean.

As you now have a Magnaclean, you can if you want add Sentinel X400 and just run the system as normal. It loosens the sediment and your filter will catch it.

X400 carries on working for about 4 weeks, however it does no harm if you leave it after that, all that happens is that as it loses power, the loose sediment settles again. However in your case it will be trapped by the filter and you will remove it, so it can't settle. You will know if it is working because you will get black sludge on the sleeve of the magnet.

If you had hard water I would have suspected that the limescale and magnetite has combined to form a hard black layer, but you say soft water, so not that.

You have to tie up the ball valve in the F&E tank and drain out a couple of buckets of water from the system before adding the chemical, so that when you untie the float it is drawn down when it refills. Add X100 as well if not already done. Bale out all mud from the F&E before you start to drain, and sponge it clean.

I am a householder not a pro.

 

[nenevall]

Ok, I suspect that the pipes are super clogged as tapping them
Reduces a dull thud, instead a cheery ding which is evident on the cold feed.

Either way I think we'll try x400 in the system (this time with a working pump!) for a few weeks, check the magnaclean.

But sure was good to wake up to a toasty house this morning.

 

[BARNY78BG]

HI THERE, SORRY, BUT IF YOU HAD AN EFFECTIVE POWERFLUSH YOU WOULDNT BE ON HERE HERE NOW, COS POWERFLUSHING GETS RID OF ALL MAGNATITE IF DONE EFFECTIVLEY.
DAVE 18 HAVE A RE THINK MATE??????
AGREE TOTALLY WITH POWERFLUSH COMPANY, TOO MANY ENGINEERS ARE QUICK TO DISMISS SLUDGED UP SYSTEMS AND THINK THAT A QUICK RINSE WITH A HOSE IS THE ANSWER,UNFORTUNATLY....... NOT!!!!!

 

[JohnD]

View media item 5880

 

[BARNY78BG]

sorry guys,caps is now removed from computer,lol, didn't realise and hope it didnt cause offense to anyone,cheers