Adding Fernox DS40 to system via magnetic filter chamber

26 Oct 2008
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United Kingdom
I'm planing to use Fernox DS40 to clear out a microbore blockage. I can't use the one of those funnel things for radiators as the radiators are quite narrow and do not have the type of bleed valve where you can screw in the funnel.

The heating system is closed, but it does have a MagnaClean filter installed. Can I take a rough guess as to what the total volume of the central heating loop is and then put the required amount of DS40 power into the MagnaClean chamber?

My concern is that when the water first mixes with the powder, it will form a very concentrated acid initially which may cause damage to the CH system.
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Need a bit more info as in what system you have and why you think there,s a blockage.
Whats the symptoms.
DS40 will not clear a blockage if there is no flow DS40 cant clear it, if you have poor flow it might help
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It's a Valliant boiler with microbore pipes. All the radiators work fine apart from one. That one radiator takes far longer to heat up and when it does, it is only warm whereas the other radiators are hot. Rebalancing the radiators did not help.

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