MagnaClean - Report #1

[TheScullster]

Hi Guys

A number of people expressed an interest in the effectiveness of the MagnaClean magnetic central heating filter. Having run the system for a few days, I opened the unit last night to check the state and found about 2mm (average) of sludge cover on the core. On the strength that other users have found these devices "impressive", I draw the conclusion that the amount of *free floating* magnetite in my system is low.

But, I know there are issues with the system as I cannot run with less than

2 rads without pump over occurring. Therefore the system flow rate will be low and the tendency for crud to just sit on one place (rather than obligingly head for the filter) will be high.

To try to mobilise as much solid stuff as possible I propose to:

Turn boiler stat off so it won't heat circulating water. Block the vent pipe to stop pump over. Wind the pump up to speed 3 (now speed 2). Shut down all rads except one (with control and L/S valves on this rad full open) and start pump by winding up room stat. Hopefully this will move the crud around and bring it to the filter. Repeat procedure for all rads in the house. Re-check filter to see if this is more successful. Unblock vent pipe. Drain system and refill with more sludge remover.

Comments/improvements welcome.

Phil

[Cicero]

========================= It's just remotely possible that you could pressurise the system by blocking the vent pipe. It would be sensible to turn off the cold feed to ensure no extra water is drawn in during your *exercise*.

Cic.

[Doctor Drivel]

2mm is quite a lot really. This may have ended up being baked onto your heat exchanger

What type of boiler? Best convert to a one pipe (22mm) combined feed and expansion with an air ejector. Then the pump over problem goes. But you need a boiler that is capable of being used in a pressurised sealed system to do this. Most modern boiler can be and have been for many years.

As we don't need heating at the mo', blocking up the vent pipe and sending all water flow through one rad at a time will help to dislodge sludge in individual rads. Turn the gas tap to off at the boiler, before you block vent pipes. Also, any excess pressure may work its way up the feed pipe too, so this has to be blocked too.

[TheScullster]

"Doctor Drivel" wrote

Glow Worm Space Saver 50,000 Btu - undersize and due for replacement - plenty of kettling etc on start up.

This sounds interesting. Where can I find details of this arrangement? Does this simply mean teeing the 15mm water make up into the 22mm vent?

Is there a way to confirm the boiler is OK with this?

The boiler stat itself has an off position - are these not reliable?

Thanks Doc

Phil

[TheScullster]

"Cicero" wrote

Didn't think the standard Grundfos 15/50 was capable of pressurising, saw it more as a circulator. But I'll block the feed just in case.

Ta

Phil

[Doctor Drivel]

Go to the Baxi site and dowload the pdf instructions on the Promax. All is in there on a one pipe arrabngement using an air ejector.

All it is, is have a three port air ejector on the flow pipe near the boiler. Flow pipe in, flow pipe out. The vent pipe on the ejector is 22mm and take this 22mm pipe to the F&E tank. Connect it to the bottom of the F&E tank. No open vent goes over the top of the F&E. Any open vent pipe on the system must be taken off. The Magnaclean ensures that no crap will accumulate in the air ejector, and the ejector means air is expelled up the combined feed and vent pipe into the header tank. Have the flow pipe from the boiler runing upwards all the way.

The Spacesaver wasn't a sealed system capable boiler. I think that might have changed. Get all the boiler details and ring the makers.

Just turn off the gas tap at the boiler, in case

If fitting a new boiler, you may want to make the whole system pressurised. But, if the rads are corroded a bit they may pop with the pressure leaving a big replacement bill. You may want to fit a Glow Worm HXi modulating condensing boiler (exellent) using the one pipe combined feed and expansion method, as the system then will still be at low pressure.