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Flushing out a central heating system

Postby torchy663 » Thu Jun 20, 2013 5:43 pm

Is it worth flushing my system out with sentinel x400, whipping off all the rads and flushing them out myself prior to getting a new boiler fitted? Also have a couple of rads that need replacing as well so was planning to do that at the same time.

and i cant use the boiler as the H exchanger has gone so any flushing will have to be done cold, how effective will x400 be in this case?

Its an old system, boiler is a IDEAL Elan 80f and i cant find a replacement Hex anywhere. So just thinking about getting as much sludge out of the system as i can before the professionals arrive

is it worth the time and effort or should i just get the whole thing done in one go with whoever's doing the boiler install
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Postby proptech » Fri Jun 21, 2013 7:29 am

Hi, torchy663

I really would suggest that you get the professionals to do this for you. They would probably use power flushing equipment. Also the system will possibly have to be brought up to date with the current regulations, involving alterations to the pipework.
The installer will need to ensure the system is thoroughly clean, and may even insist on flushing whatever you may have done, so could be a waste of time and effort.
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Postby htg engineer » Fri Jun 21, 2013 5:57 pm

It's definitely worth the time flushing the system, the X400 needs to be circulating at normal operating temperature, so not going to be any use in this case. You can find installers want to be in and away, I'm not sure why you've chosen the installer you have - hopefully it's recommendation?

I would remove all radiators one by one and flush through with the garden hose, the more you can get out before the new boiler is fitted - the better. New boilers are more efficient, therefore have lower water content and the waterways are quite small, any sludge/debri will start causing problems for your new boiler within months, not years.

You need to clarify with installer exactly what type of flushing they will be doing, and what inhibitor they will add to protect the new boiler.

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Postby torchy663 » Sun Jun 23, 2013 8:13 am

htg engineer...thanks for the reply

the main reason i'm asking about flushing the system is that i intend to drain the system anyway as i have a few rads i want to replace, so i figured if i was draining the system i might as well add some flushing agent to try and get as much out as possible.

is there any product out there that i can use cold. If not i'll just drain the system and flush out all the radiators one by one with the hose. (would using a power washer be more effective rather than a garden hose?)



proptech..thanks for the reply.
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Postby torchy663 » Mon Jul 01, 2013 11:48 am

couple of questions

1 Is there any flushing product available that doesn't need the system to be at normal operating temperature to work?

2 Am i likely to get any problems if i leave the system drained for an extended period, say a few weeks?


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