Adding Fernox Boiler silencer via radiator

[Bonedry]

Hi

My boiler is noisy after changing the hot water cylinder a couple of months ago. I've got some Fernox boiler silencing stuff that you add via a radiator. The pack says close of rad valaves - open bleed valve and then attach pipe and mastic gun to ran. Open valve (the one you usually use to turn off & on) and inject stuff.

Has anyone done this? DId it go ok?

A search also found a suggestion to crack the radiator nut after shutting off valves to drain rad and then add it?

Anyone tried this method?

Thanks in advance

John

 

[ChrisR]

Is it in a syringe?
Those you can inject via an air vent.

Got a towel rail??

 

[Bonedry]

HI Chris

It is in a mastic tube - which I suppose is like a big syringe - I have no towel rail.

I'm just concerned as you will be pushing against the heating system. I'm thinking of using the upstairs bathroom radiator.

Cheers

John

 

[ChrisR]

Drain a little water from the rad then. Shut valves and crack one of the unions open.
What do the instructions say?!!!

 

[Bonedry]

The instructions were as my first post turn of rad valves - remove bleed valve - screw in mastic gun to bleed valve open radiator valve and inject. I was hoping to hear if someone has done this method ok.

I might try it and if a problem crack the nut and drain.

Cheers

John

 

[gblades]

I have done this before but with inhibitor rather than the silencer.
I have a combi system so I just undid the drain connector downstairs to bleed off the extra pressure and then tightened it up again.
Then on an upstairs radiator I removed the bleed screw which causes air to go in and the water level to drop. Then squirt in the stuff and do everything back up again and repressurise the system. Go round and bleed the radiators and leave it running for a while and then bleed again.

 

[Bonedry]

Well I added it - it came out of the bleed holw but with a finger on that you could here it going in. I cracked the rad nut and drained the water from it but maybe you can do it as per instructions if you put a thumbe or clamp the bleed hole.

I wouldn't say it was easy but it can be done now lets hope it works. I wondering if my leak contributed to the noise by leting in some air.

Cheers

John

 

[Bonedry]

Thanks to Chris & GBlades for their quick replies!