Filling a duel fuel radiator.

[sjl468]

Hi.
I've just been asked to install a Duel fuel towel radiator in a bathroom. I'm only going to fit the heating element and not connect it to the central heating system. Can anyone tell me what is the best fluid to fill it with please? If it's just water, is there any additives that should be used?
Cheers.

 

[AlanE]

If you intend simply sealing the openings intended for the heating water how do you intend allowing for expansion of the water, or other fluid, in the towel rail?

 

[Elkato531]

Why not buy and fit an oil filled electric only towel rail?

 

[bengasman]

The answer is: you don't, because it is too dangerous.

 

[sjl468]

I'm going to fill it up and turn it on few a few mins with the bleed valve open and when all is expanded close the bleed valve.
It's not for me. It's for a client. She has already bought it and had it delivered. I did originally think she'd ordered an oiled filled one.
It came with just the electric element and T piece. No instructions as to what I should fill it with, just instructions on how to connect it to the central heating system.

 

[Elkato531]

You must refuse to fit it. She ordered it in error and the mistake is hers.
If you fit it in an incorrect way and something goes wrong you won't have a leg to stand on. Possibly literally.

 

[sjl468]

Ok. Thanks for that. I'm not a plumber, just an electrician. Never been asked to fir a "Dual fuel" radiator before. But it came as a kit. I'll get in touch with the manufacturers.
Thanks for your help.

 

[kevplumb]

I'm going to fill it up and turn it on few a few mins with the bleed valve open and when all is expanded close the bleed valve.

what happens when it cools and you get a vacuum

 

[bengasman]

I'm going to fill it up and turn it on few a few mins with the bleed valve open and when all is expanded close the bleed valve.

what happens when it cools and you get a vacuum

Water will boil.

What is more interesting, is what it will do when the thermostat fails to turn the power off.

 

[leakydave]

You could leave it half full of air, allowing for expansion, but it is a dodgy job and don't fit it. Change it for the proper oil-filled electric only jobbie.

 

[bengasman]

You could leave it half full of air, allowing for expansion...

How would that protect against a failing thermostat?

 

[kevplumb]

You could leave it half full of air, allowing for expansion, but it is a dodgy job and don't fit it. Change it for the proper oil-filled electric only jobbie.

if you leave it half full of air the top half won't heat

 

[leakydave]

Oh take a joke!!! Read the rest of my post.... "Don't fit it!"

 

[kevplumb]

my apologies dave i obviously took it out of context

 

[AlanE]

However you try to allow for expansion the internal pressure will rise above what it is designed to take so sooner or later it will give way!!