Advice on draining and refilling CH system.

[Bongowhack]

Hi all, I'm after some advice as I'm planning on moving a radiator and think I need to drain off at least part of the CH system.

The radiator is only going to be moved by about 6 inches but it's necessary as Persimmon put it in a daft place when they built the house a few years ago.

Our boiler is a condensing Glow Worm 15hxi and most of the pipework around the house is either the 10ml or 15ml push-fit grey plastic type. I'm looking to drain the system, fit a short extension to the existing pipe behind the radiator and then refill the system again.

Now draining the system sounds easy enough - isolating the boiler & pump then draining the water through the (many) draining points around the house. The thing is that I don't want to start the work until I know for sure I can refill the system and it's that bit that's got me puzzled.

I've done very basic work on CH in the past but I think they must've been closed systems as I've had a valved inlet pipe as well as a pressure gauge to play around with.

With this system however, there's nothing of the sort and I'm at a loss as to how to put water back in to the system once it's been taken out.

The boiler itself only has flow and return pipes coming from the top and there's no way, that I can see anyways, of knowing what the pressure in the system is. On a side note, the inside of the boiler shows no resemblance to the one in the pdf manual online (in their infinite wisdom Persimmon decided not to leave us a copy).

Can someone please tell me how to get water back into the system after I've taken some out and also how to check the pressure so I can replace the right volume.

Thanks very much.

Mike

 

[tomy]

Sounds like a standard tank fed system , turn off the cold water main to drain the system or tie the ballcock up in the small tank in the loft , then when you have finished working on the pipes either turn the water back on or untie the ballcock , then bleed all the air out , you only need to drain off from where you are working untill the water stops coming out , no need to drain it from every drain point .

 

[Bongowhack]

So the system will refill itself & pressurise as necessary from the small tank on my loft once I connect it all back up? That's the only other thing I could think could possibly happen but it just sounded too easy!

On a side note, I happened to check the small tank in the loft this afternoon and it had a layer of rusty gunk floating on top. First off is this usual and if not, what's the best course of action to clean it up?

Thanks again

Mike

 

[tomy]

Yes thats right , it will fill itself up , just make sure you bleed all the air out , as for the gunk on the top of the water in the tank , no thats fine it will just get rid of it when you drain it , it is nothing to worry about .

 

[Bongowhack]

Thanks for that - all I need to do now is find somewhere that sells 10ml pipe. Been to the usual suspects of B&Q etc and they only sell it in 50M rolls!

I only need about a foot - any bright ideas?

Thanks,

Mike

 

[tomy]

Ask a local plumber if he has an of cut that you can have

 

[Whitespirit66]

Or, buy it by the metre on that famous online auction site

http://cgi.ebay.co.uk/JG-SPEEDFIT-1...DIY_Materials_Plumbing_MJ&hash=item4cf513f0b7