Add leak sealer through Magnaclean filter.

21 Sep 2015
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United Kingdom

Thank you in advance for your help.

There is a small leak somewhere in my heating system. I can't really see any trace of water anywhere in my house so I presume it must be somewhere underneath the first floor.

Before calling a plumber and or lifting my lounge floor, I'd like to try by using one of this miracle Leak Sealers that find and seal small leaks.

To me, the easiest way to add it to the heating system would be by opening the Magnaclean filter and pour it through there. I've opened it and cleaned the magnet twice in the past, so I have experience dealing with the filter.
My only concern is if the liquid is going to damage the magnet or the boiler itself. Leak Sealer are usually added through radiators, hence concern.

What do you think?

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My boiler make and model?
The only thing I can tell you now is that it's a combi boiler. I'll let you know more details as soon as I get home.
If it's a combi then the most likely place to be losing pressure is out of the pressure relief valve. Tape a sandwich bag over the outlet and see whether it fills up with water. Boiler make/model would still be useful though
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It's an Ideal LOGIC+ Combi (24, 30 or 35).
I've lookid very well around the boiler and all it's dry. I presume the relief valve it's inside it?
Considering I have to add water to the system every 2 weeks , any leak should be very obvious. That's why I think it's underneath the ground floor.

Using a Leak Sealer would be the first step to try to fix it. Second step would be look underneath my lounge floor. Third step, call a plumber :)
It's an Ideal LOGIC+ Combi (24, 30 or 35).
This might be the root of your problem, but we'll come to that in a minute....

Keep your leak sealer well away, nasty stuff. The pressure relief valve is inside the boiler but the termination is a copper pipe on an outside wall, usually near the boiler. It might also look like a circular brass cap

If that's not running then we come to the reason why the boiler might be at fault - Logics are known for suffering from cracked heat exchangers, which let the central heating water leak out of the condensate pipe. Depending on the age of the boiler and whether you've had it serviced annually, it might still be under warranty. If not, expect to pay around £400 for an independent to repair.

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