Replacing old radiator with Heated towel Rail

[AnnaA1982]

Hi All

Now i know this topic has been posted a hundred times but im still not clear on everything, so thought id check and clarify my plan...

So im no plumbing expert but am confident i have enough DIY skills to do this myself.

Firstly I understand i have to drain down the CT system before i start.
I assume this involves turning the stopcock, turn off the boiler (i have a combi so no water tank) then draining water from the rads. (i have no drainage valve) am i right in thinking i will only have to partially drain the system as its an upstairs radiator therefore the water will drain to the lower half?

secondly the existing pipework is 10mm and most of the towel rails are 15mm so i intend to cut/adjust the pipes under the floorboards to fit the size/width and then use a 10-15mm reducer to change the pipe - Will this be ok?

Finally top the boiler back up via the filling loop and job done!

Am i missing anything?

Thanks in advance!

 

[Burnerman]

Basically thats about it, but there's no need to turn off the stopcock as the C/H is a sealed system.....it means that your house still has mains water.
Obviously turn the boiler off.
Depressurise the system by cracking open the rad connection nuts (shallow tray handy) and open the rad bleed valve to drain that.
The rest of the system may drain a little, but naturally not the downstairs.
Use a 10/15mm reducer for the pipe work (with copper olives) if possible.
Towel rails put out only a small amount of heat compared with a radiator but presumably you've considered this. Flush out the new rail before you fit it!
You'd maybe like to add some more inhibitor to your system as the work progresses.
John

 

[AnnaA1982]

Thanks for the help John really appreciate it!

We only have a tiny bathroom so shouldnt need a huge output from the radiator.

I will get some inhibitor i presume its ok to mix it with whatever inhibitor is already the system.

One last gerneral question when filling the system back up are you suppost to leave the bleeding valve open slightly to reduce the air? (obviously close when water arrives) Ive always thought you could do that afterwards and top up water as needed!

 

[Burnerman]

If I'm working alone, I increase the boiler pressure to about 1.5 bar, close the filling loop and head for the rad in question - bleeding it until alls done or the pressure drops......then its back to the boiler again for refilling.
Once the rads are purged of air, then I'd set the boiler pressure to the recommended figure (about 1 bar usually, but to whatever it was before).
Then its heating on, and rebleeding as necessary for the next few days as fresh water will allow some oxygen to be released.
As far as I know, inhibitors are compatible with eachother but I don't use the no nonsense stuff - its Fernox F1 for me in the injectable concentrate form.
Enjoy your project and take your time - leave the floorboards up until you're sure there aren't any leaks down there.
John