fernox silenser

5 Jan 2007
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United Kingdom
hello everyone,
can someone tell me how long you can leave fernox silenser in your boiler? my boiler was kettling and i called out my regular engineer. he put fernox silenser in one of the radiators. this has stoped the kettling.
the only problem is he has travelled and wont be back till next week. this means the fernox silenser will be in the system for about a month.
i understand it has to be drained after a week and refill the system and therefore i am worried. my boiler is a glow worm economy plus.
should i be worried?
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many thanks kevplumb. i can go to sleep now. hope to get him to drain the system next week.
I thought the *silencer* was to stay in indefinitely :confused:
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sorry i dont know much about central heating. as far as i know this will be drained. one can then put in fernox protector that can stay in forever. i may be wrong though.
Hi Everyone,
My boiler was banging, spluttering and noisy for a long time- 20 years to be accurate.

Then, last year I drained the whole system. But this is important. Before you drain the system, please also open the diverter-valve manually(there is a small lever to do this easily)) if you have one . I did not do this vital operation during the previous 20 years when I drained the system several times and the blasted noise persisted.If you do not open this valve, you
cannot drain out the muck accumulation in the boiler that gets carried into the radiators as well.

Then I forced sludge- remover, directly into the outlet of the feeder tank and left it for about a month. If this liquid doesnot go in easily clean the outlet pipe with a small 13/14mm.dia. spring-(available at any reputable harware stores) which is similar to a pipe bender spring.Then block the outlet opening with your finger or thumb and then let go suddenly.

Repeat this operation several times until your feel a slight suction force on your thumb/finger, to block it on and off, as if to induce a water-hammer action.

You must be able to hear this action. I heard and felt it.This is to make sure the feeder pipe to the boiler is not blocked. There is no use pouring the sludge remover into the feeder tank if this pipe is blocked.

Then I drained again, remembering to open the diverter-valve manually,
filled it with inhibitor and presto no noise so far for about an year now. My boiler is just purring away. But please repeat this process annually as you would with a car service.Fernox silencers are blooming expensive and it may not work without de-sludging first. Also empty and clean the feeder tank using a sponge, for the last drops, annually.Good luck
Thanks Corgiman,
You are right in saying I was referring to de-sludger. I could not see anything saying you should not drain, in the web page you referred. It says 'recommend system are cleansed' How does one do this comprehensively with draining the system, When I drained the system after 4 weeks of sludge-remover in the system(according to the instructions) it took more than an hour of continuous gravity flushing via the feeder tank to get almost a colour less water.

I too was surprised that this method worked very well.
corgiman said:
if its bad then think about getting it powerflushed

ds40 corgiman!

Be young and brave!!!

Mind you, ive gotta change a new world stowaway heat ex tommorow, and im feeling 'not so brave'

Never done one. Advise????


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