Magnaclean

[Matthew]

Has anybody used the magnaclean CH strainer that I have seen advertised here:

thoughts? looked like a good idea... But quite expensive

Thanks, Matthew

[EricP]

Looks like a license to print money. I thought corrosion inhibitors changed periodically were supposed to do this job?

[Doctor Drivel]

They work very well. They also get all solids not just iron. Discountedheating sell them cheaper.

[andy hall]

Is there a mechanical filter as well?

The claimed 100% flow rate suggests that there isn't.

Given that there can be other crud such as copper and brass swarf and other non-ferrous material in a system, the product could not correctly be claimed to remove 100% if it is purely a magnetic device.

Iron oxide sludge appears in a system for a number of reasons including:

- lack of corrosion inhibitor

- a fault in a vented system allowing oxygen to be continually reintroduced

Other unwanted materials can be introduced by lack of cleaning, association of dissimilar metals and so on.

If a system is continually producing sludge to the point that a device like this were needed, then it is because fundamentally, the radiators are rotting away.

While it is certainly important to prevent particulate matter from entering a heat exchanger, this device is addressing it in the wrong way. It should be prevented from happening in the first place, and that is easy to achieve. A correctly installed and dosed system should not be producing any significant amount of sludge, and a simple stainless steel strainer type of filter is quite adequate.

[Doctor Drivel]

Matt, look at their web site.

It is not purely magnetic

[andy hall]

Then explain how it maintains 100% flow if there is also a mechanical filter.

They can't have it both ways.

Either there is no mechanical filter, in which case not all the crud can be removed, or there is a filter, in which case there can't be 100% flow

[Doctor Drivel]

Matt, read the web site.

[sPoNiX]

Or the non magnetic crud falls into the bottom and can't get out again due to gravity..?

[sPoNiX]

Dyson makes exactly that claim for their vacuum cleaners...

sponix

[Aidan]

Probably means 100% of the flow going around the system ( rather than side-stream filtration taking a portion of the flow) although I can't be bothered to look at the web site. This 100% could be a problem, if there is a mechanical filter, in that it will restrict the flow. If neglected, the flow rate will drop excessively, possibly wrecking boilers & pumps. There should be an auto by-pass around the filter (and there may be, I don't know) to ensure adequate flow is maintained.

You wouldn't need this if the system hasn't been allowed to corrode in the first place. If you do need it, magnetite sludge is adhesive and sticky (it's magnetic!) and very difficult to shift without manual scraping. It's usually stuck inside pipes & rads, not in suspension, so a filter wouldn't be able to catch it. A flocculant might help get it into suspension so the filter can catch it. If it's really bad, I think you'd do best to replace the excessively restricted pipes.

There's auto backwashing filters available. Honeywell/Braukmann used to do one, may still do. Some American one too, forget name, reportedly very effective, but commercial sized only.

[Doctor Drivel]

Alpha boilers have a cyclone filter on the return of each boiler..

[andy hall]

Mmmm...... I don't believe that either.

It would be much more effective if they claimed a substantial improvement rather than 100% which clearly can't be true.

[John Rumm]

Dyson claim that the cleaner does not lose suction. That is not the same as saying that a cyclone separator does not introduce flow resistance (which it does).

[Will]

As the initial suction takes into account the flow resistance due to the cyclone arrangement, then, barring a blockage within the cyclone, the suction will not reduce in use in this area.

However, the dyson cleaners all (iirc) come with filters of one type or another, with by definition increasingly block with use...

So the "100%" claim is patently untrue.

[Lurch]

On or around Sat, 5 Nov 2005 12:30:35 -0000, Will mused:

100% of what exactly?

[Will]

See

extract of which is:-

"After five years and more than 5,000 prototypes, the world's first bagless vacuum cleaner from Dyson was born.

The design was not just different, it was better, claimed Mr Dyson. While conventional vacuums lose suction as the bag fills with dust, the Dyson cleaner maintained "100% suction, 100% of the time".

This happens to be the first cite that I came across, there must be many more...

[Lurch]

On or around Sun, 6 Nov 2005 10:05:23 -0000, Will mused:

100% of what though?

[Matt]

While I could almost believe the 100% suction bit the "5000 prototypes" that is continually banded about is so utterly ridiculous, especially in the context of a one man band development "team"