rad valve with integral drain off

[danlightbulb]

Hi,

Do these valves http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=102636&ts=93259&id=11074 drain off the radiator when closed, or do they drain off the pipework?

I have these on a rad and need to remove the rad but don't want to drain the whole system.

Thanks

 

[hi-spec plumbing heating]

both.

if only draining rad shut valves and slacken the nut on the inside of rad valve and drain into a bowl

 

[Rob]

Looking at it it should just drain the rad if the valves at both ends are off.

 

[Aquaheat]

These drain off system not radiator. To drain the rad without system drain:

1/ PUT DOWN DUSTSHEET!!!

2/ isolate flow and return valves

3/ with a small container of some sort crack the valve union and release the water into your container. After a short while you will be able to open the vent to allow air in and this will increase the flow.

4/ continue until no more water is coming from the rad and you will be able to disconnect both unions.

5/ BE AWARE THERE WILL STILL BE A SMALL AMOUNT OF WATER IN THE RAD THIS WILL BE FULL OF MAGNETITE AND WILL STAIN!!!!

6/ best to use an old rag or similar and insert into the 2 openings to prevent any further water loss

7/ Replace vent plug

8/ Remove rad from wall and flip upside down at the earliest oppurtunity.

et voila.. rad off wall, carpet still clean!!?? (hopefully)

 

[danlightbulb]

Ok thanks.

When I reinstall the radiator, should I add some corrosion inhib directly into it (before I repressurise) to maintain the system concentration. It is a very new system (2 months).

Cheers

 

[JohnD]

a plastic tray (as used for roller paint emulsion) is handy for catching the water as it fits under the nuts

Good idea to put a bit more inhibitor in, though not essential if the system was properly inhibited (a litre of chemical will do for 100 litres of water, which is about 10 rads worth). As the system is fairly new I hope you will find the water is very clean. if not, especially if you get black sediment out, or you suspect it was not flushed and inhibited when installed, you could drain and flush it, and refill with inhibitor.

If inhibitor was used at installation, there will with luck be a label near the boiler saying what brand was used. sentinel and fernox are good brands.