Fernox F4

[RichD1]

I have a small drip on one of the copper solder joints underneath a radiator. System is a combi pressurised.

I'm going to give Fernox F4 a try, but the instructions does not say whether the system should be drained and flushed if the leak has been sealed.

Do you leave F4 in the system and can you then add the normal system protection fluid?

Richard

 

[PrenticeBoyofDerry]

But the sealer into a cold system via a radiator, you may have to draw off/ drain down a few litres of water first, then top system back up and run the central heating at a low heat.
It should be okay then to add inhibitors if required.

http://www.fernox.com/problem+solving/how+to+sheets/repairing+leaks

 

[RichD1]

Yeah, I'd read the instructions but wasn't sure whether you cleaned the system out once leak had been cured or left it in.

Richard

 

[PrenticeBoyofDerry]

Firstly is the joint accessible or can be made accessible to fix?
If the joint is not causing damage beneath it, I would do the flush and chemical clean first.
But if you are draining down, which you will if adding chemical cleaner, then repair the joint!

With regards to whether a chemical clean/flush is required, would depend on the condition of the fluid in the system?

 

[RichD1]

The joint is visible but it's in a tight location which would require quite a bit of dismantling to repair. Is there such a thing as a sliding solderless fitting? This would allow me to cut out the problem joint and insert a repair section without having to move all the other pipework.

Richard

 

[TCCHeating]

Is there such a thing as a sliding solderless fitting?

Yes. It is called a 'slip coupling'. You can get them in both compression and end feed.