Moving a radiator

[danrhope]

I want to move a radiator from on wall to another, removing the existing pipework and putting in new. The below image shows pretty much what I want to achieve.

First things first: I am very new to this lark...I have tons of common sense (don't believe my girlfriend she's lying) but am just really entering the realm of home ownership and DIY so any advice would be greatly appreciated.

I'd like to know firstly how to drain the system. I'm in a top floor flat in a victorian conversion with only 3 radiators: lounge, bedroom and bathroom, all on one level. It is the bedroom on I want to move to be on the opposite side of a partitioning wall to the lounge radiator. It is a sealed system (I think, from what I have read) and have a combi boiler.

This diagram on this page I found seems to accurately represent what I have. http://www.diyfaq.org.uk/plumbing/combi.html#intro

The only stop-cock and drain that I can find in the whole system is on the ground floor in the meter cupboard which I can only assume serves all 4 flats.

Please give any advice in reasonable detail, explaining exactly what I should shut off (and where it is!) and where I should drain from (if at all)

And once I have done this is it okay to plumb in the new pipes off the ones feeding the lounge radiator? I can't see why this would be a problem but thought I should ask!

Thanks in advance!

Dan
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[Softus]

The below image shows pretty much what I want to achieve.

Nice image BTW.

I'd like to know firstly how to drain the system.

The basic principle is to isolate, find a drain point, attach a hose (or wet vac), and open the drain cock. Note that the contents of the heating system is a category of fluid that must be passed to the sewer for treatment by your sewerage company. Sticking the other end of the hose into the WC pan would suffice.

I'm in a top floor flat in a victorian conversion with only 3 radiators: lounge, bedroom and bathroom, all on one level.

If you can't find a drain point then you're going to have to drain from a radiator union. The best way, for you, is to shut all rad valves, slacken a joint between one rad valve and the pipework, catch all liquid in paint trays and such like, attach a short length of copper pipe to the hose (with a jubilee slip) and then with nut and olive onto the rad valve, then open all rad valves to drain all rads. Also open all vents to allow air in to replace the water. If you do this from the bathroom rad then you'll avoid risking damage to lounge/bedroom carpets.

The only stop-cock and drain that I can find in the whole system is on the ground floor in the meter cupboard which I can only assume serves all 4 flats.

I would be surprised if this was part of the heating system - more likely that it's the cold mains supply. However, it's unlikely, albeit not impossible, that you have only one stop cock for four flats.

In any case you don't to shut off all water in order to drain the heating system. The boiler should be isolated from the cold mains by default, but check that the filling loop hose has been disconnected (or that there is a valve that is closed).

And once I have done this is it okay to plumb in the new pipes off the ones feeding the lounge radiator?

Quite often there are reasons not to do this, but in your case, because the 15mm pipework would be serving only two rads (if I've understood you correctly), then it would be OK.

 

[danrhope]

Thanks for the reply Softus...very useful.
So what do I have to do before I get to the stage of actually draining the system? I assume that I have to turn the boiler off but after that does anything need closing off before I start draining away?

 

[Softus]

Yes indeed - turn off the boiler - I probably didn't make that clear enough.

Regarding isolating from the mains, the boiler ought to, but might not be, already isolated. Look for the braided steel hose called the "filling loop", and check that it's either disconnected or that there is a closed valve in the loop (or at one end of it).

Certain boilers have other filling methods, if you can't find a filling loop then please post the brand and model of your boiler.

 

[danrhope]

yep there's a braided pipe that goes between the "Domestic Cold Water Inlet" and "Central Heating Flow" pipes of the the boiler.

So I just leave this as it is, turn off the boiler and get draining then? One post I saw says to turn off the gas to the boiler, is this necessary?

 

[Softus]

yep there's a braided pipe that goes between the "Domestic Cold Water Inlet" and "Central Heating Flow" pipes of the the boiler.

So I just leave this as it is, turn off the boiler and get draining then?

Yes.

One post I saw says to turn off the gas to the boiler, is this necessary?

If you don't trust the means of electrical isolation, then it would be prudent to shut the boiler gas cock, but otherwise I can't see any risk with leaving it open.

 

[danrhope]

oh and the loop has a valve at either end...I tried opening the one on the "Domestic Cold Water In" end, expecting to see the pressure rise but nothing happened. And the other end was a bit tricky to get to and the pipes were hot so I didn't persevere.

 

[danrhope]

Thanks again for your advice softus...I've got a lot of time for people who are willing to give it out free. If ever you're in need of some computer animation info don't hesitate!

One last question I (almost) promise. When I turn the boiler back on and refill the system, and have bled the radiators...will I then need to open up both the valves either end of the braided loop in order to bring the pressure back up to 1bar?

Cheers

Dan

 

[Softus]

Thanks again for your advice softus...I've got a lot of time for people who are willing to give it out free. If ever you're in need of some computer animation info don't hesitate!

You're welcome / cheers / thanks in anticipation

One last question I (almost) promise. When I turn the boiler back on and refill the system, and have bled the radiators...will I then need to open up both the valves either end of the braided loop in order to bring the pressure back up to 1bar?

Quite so - you have indeed understood all the basic principles. Although the turning-on-of-the-boiler action should come last, after filling and venting.

Please let us know how you get on.

PS Don't forget to add a chemical inhibitor when you're sure that all work is done and there's no more drain/refill cycles to do.

 

[danrhope]

okay there you've just proved that I have no grasp whatsoever of the principals involved!....

presumably if I am able to drain the system and work on it when I have turned the bolier off there is no water-flow. So how does the system fill again without the boiler being involved?

Sorry...I'm sounding proper thick now..

 

[Softus]

No - I still think that you've understood.

You refill by (a) closing all rad vents and valves, then (b) opening the valves on the filling loop/hose until the correct cold pressure is reached.

I make the distinction between doing this and turning on the boiler because the last action, after venting, will be to turn on the boiler electrically.

 

[danrhope]

got ya...thanks again

I'll let you know how I got on after the weekend!!

 

[Softus]

Bon chance!

 

[danrhope]

Well how easy was that!!!!???

Thanks very much for your help Softus. All I did at this point was remove the pipework for the old radiat as I haven't the the new one to fit yet but now I feel confident draining the system and using compression joints so putting in the new radiator should be a piece o cake!

Thanks again

Dan

 

[Softus]

Sounds good Dan. Keep your head though, and don't make the mistake of rushing - that's when things go wrong.