drain whole system or not

[bunser]

I need to change the room stats on 2 bedroom rads. Do I have to drain the whole system? and would it be a down stairs rad that I drain it from?
I have a cylinder in the airing cupboard up stairs and a boiler on the wall downstairs with 2 tanks in the loft
Thanks

 

[D_Hailsham]

You can use a Drayton DrainEasy Kit (from B & Q etc). This is a couple of rubber plugs which are used in the Feed and Expansion tank - the small one in the loft. One is inserted in the outlet from the tank which feeds cold water into the heating system; the other is inserted into the vent pipe which hangs over the tank. If you then open a bleed valve some water will come out for a short time and then stop. This is because a vacuum has been set up in the pipe work. Now shut the bleed valve. Shut the rad valve at the opposite end to the one you are replacing. You can then remove the rad valve and replace it. Do one valve at a time.

You will loose water from the rad itself, so you really need a plastic sheet, plenty of old towels and a bucket to protect the carpet. While you are changing the valve, why not remove the rad completely and flush it through with a hose?

If you pipe comes up through the floor, you will see the water level just below the top of the pipe.

Note: The DrainEasy kit will not work if the tanks is more than 30ft above the rad. This is because the vacuum will not hold.

 

[spacethegas]

i've seen this recommended lots of times before & i think its a bad idea to ask diyers to attempt this.
just drain the upstairs rads.
its safer & will take 30 min longer max (even for diy man).

 

[bunser]

I have taken the rads off but surely I need to drain the water level down before I take the valves off?

Thanks

 

[D_Hailsham]

I have taken the rads off but surely I need to drain the water level down before I take the valves off?

Not if you use a Drain Easy Kit.

 

[bunser]

Will pop to b&q to have a look, any ideas on price.
Also will I still need some towels etc as some water may escape untill the vacuum takes hold?

Thanks

 

[D_Hailsham]

Will pop to b&q to have a look, any ideas on price.
Also will I still need some towels etc as some water may escape untill the vacuum takes hold?

About £12 when I bought one last year.

As you have already removed the rads, you will need to bleed another rad to set up the vacuum. Provided you follow the instructions carefully, you should not get any water escaping from the pipe when you remove the valve. But it's always wise to be safe, as the black stuff you often find in CH water will ruin your carpets, so put some plastic sheeting on the floor and wrap the pipe in old towels, just in case.

Do one valve at a time and bleed a rad between valves to ensure the vacuum is still OK.

Edit:

You can also set up the vacuum by slightly opening one of the valves on a removed rad and collecting the water in a container. When the water stops running the vacuum has been created.

 

[bunser]

Thanks for your help

 

[bunser]

Hi,
Went to b&q but they did not have a clue and I couldn't see anything on the shelves.
Is there anywhere else that may have it

Thanks

 

[D_Hailsham]

b&q ... did not have a clue and I couldn't see anything on the shelves. Is there anywhere else that may have it

It is listed on the B & Q web site (search for Drain Easy). You can also check online if your store holds them.

Any plumbers merchant should have them

 

[jmower]

And after all that time your spending trying to find it you could have drained it down by now.

Be old fashioned, drain it all!

 

[superdupergasman]

Two carrots will do the trick!!!

 

[D_Hailsham]

And after all that time your spending trying to find it you could have drained it down by now.

Then we will get a new problem: I've drained and refilled my system and now I am getting cold rads. Do I have an air lock? How do I get rid of it? etc etc.

In any case, I expect the OP will have another occasion to use the kit.