Adding Sealant to CH system - Old Radiators and Conventional Boiler

[Deleted member 120051]

Hi folks,

I have had issues with the central heating plumbing leaking, in this (very old) house, over the last 4 or 5 years since I moved in. I know a plumber who added Fernox sealant and after this failed to work, Corgi sealant to the system, which stopped the pressure from dropping for a consistent 14 months.

Since yesterday, the pressure has dropped to below 0.5Bar despite re-pressurizing the system, it has dropped again today.

I ordered the same Corgi sealant that worked in the past, but not sure if the plumber will be able to make it over any time soon to add it. I noticed that he added it into the system where the conventional hot water tank is, in the past.

I ordered one of these "Eezyfill" adapters to add the sealant to the system, but the radiators in this house are ancient.

Perhaps I would be able to isolate a part of the plumbing next to hot water tank (e.g. magnetic filter) and then add the sealant in there, before re-pressurizing and running Central Heating?

I would greatly appreciate any advice in layman's terms...

Many thanks

Tom, Belfast.

P.S. I have attached some photos showing the pipes and plumbing trying to figure out where he added the sealant and how

 

[Ric2013]

Yeah, you could stick it in the filter. My only concern is that your next post will be 'help my Magnaclean is leaking since I took the lid off'. If you're confident taking the top off your Magnaclean though, then go ahead.

In theory, the right way to tackle this would be to find the leak and stop wasting time with leak sealer - not always possible though.

 

[Deleted member 120051]

Yeah, you could stick it in the filter. My only concern is that your next post will be 'help my Magnaclean is leaking since I took the lid off'. If you're confident taking the top off your Magnaclean though, then go ahead.

In theory, the right way to tackle this would be to find the leak and stop wasting time with leak sealer - not always possible though.

I think it's due being cleaned as it hasn't been opened since it was installed 4 years ago.

I think that the leak is in the ceiling of the living room... last time it leaked 14 months ago there was water dripping down there through the light fixture

Perhaps I should simply get that repaired! Would make a lot more sense in the long run wouldn't it...

Will have a look at this magnetic filter and the sealant. It has valves on I/O which makes me worry less about it... I had read online that model of mag. filter can be leaky though.

Thanks for the advice.

 

[Ric2013]

I think it's due being cleaned as it hasn't been opened since it was installed 4 years ago.

I think that the leak is in the ceiling of the living room... last time it leaked 14 months ago there was water dripping down there through the light fixture

Perhaps I should simply get that repaired! Would make a lot more sense in the long run wouldn't it...

Will have a look at this magnetic filter and the sealant. It has valves on I/O which makes me worry less about it... I had read online that model of mag. filter can be leaky though.

Thanks for the advice.

Yes those Magnacleans are a nuisance. Sometimes hard to open, sometimes hard to seal. Price the manufacturer wants for spare o ring seals is hilarious.

If you get the lid off okay, pop some silicone grease (has to be silicone grease - nothing else!) on the threads and the lid O ring (perhaps using an old tooth brush) if you have some to hand as this will help.

It sounds like you are assessing the risks sensibly. Wishing you the best with this, but as you say, it will almost certainly need cleaning anyway.

 

[SJB060685]

Leak sealant is a short term fix to get you out of trouble momentarily. You really aught to find the location of the leak and repair.
Sealant could be induced through the mag filter, alternatively through the filling loop or rad when done the correct way.
Any magnetic and non magnetic filter should be annually checked and cleaned along with boiler/system service. If its been four years untouched and your system is fouled then it probably won't being helping at all.