Electric towel rad

[Justin Clarke]

I have recently moved into a house with electric only towel rads. These are not getting hot at the top. I have bled them but little or no air came out and it has made little difference. I assume it is a case of topping them up. I would be grateful if anyone can recommend how best to do this when the rads are fitted to the wall (would rather not have to take them off). Thank you for any help or advice.

 

[terryplumb]

Take pic of top of rail. The bleed valve is usually removable and you can top up there via a funnel. I assume there is no connection at all to the central heating ,I.e no pipework at base of towel rail. By the way you do not fill totally ,you must leave room for hot water expansion .

 

[Justin Clarke]

Thanks - yes it has a bleed valve at the top which I can undo fine. Definitely not connected to the central heating as the inlets are capped off where the pipes would go. How much would you leave for expansion and would you put some inhibitor in it? Thanks again.

 

[terryplumb]

Yes you can add inhibitor. As you don't know the volume that the rad holds ,nor what's currently in it ,a " broad brush " approach to topping up would be to just cover the top rail .

 

[Justin Clarke]

Great thank you.

 

[JohnD]

Not connected to the central heating pipes? Just electric?

some of those electrically heated towel rails are delivered filled with "special oil"

 

[ReganAndCarter]

Drain out what's in there, and refill to 90% of volume with a solution of inhibitor and water. Definitely needs some expansion room.

 

[endecotp]

Note that you can buy mini bottles of inhibitor for this, if you don’t have a big bottle hanging around with a drop left.

My towel rad came with instructions about the amount of expansion space needed, as a fraction of the volume. If you search you might find instructions with the same info. My “A-level physics + wikipedia” guess is that the water will expand worst-case 2%. Add a decent safety factor on top of that.

If it was just the top rung that was not getting hot, it’s possible that it was fitted by someone following instructions....

 

[terryplumb]

Not connected to the central heating pipes? Just electric?

some of those electrically heated towel rails are delivered filled with "special oil"

Good point john ,totally forgot about those.