"Ed Sirett" wrote in message
...
GB wrote:

"Ed Sirett" wrote in message
...
Adam Topp wrote:

Hi,

I have just acquired a heated towel rail, which, when looking at the
spec. is designed apparently for use on a closed system only. Our
system is open vented. What is the difference between a radiator
designed for use on a closed system as opposed to an open one. I
cannot see much difference but I'm now loathe to put it on the
system
for fear of what it may do or damage may be done.

The instructions may be not so much about open or vented but rather
meaning it has to be used on a circuit rather than in the supply to
the
HW taps.

On flats in North London built between the wars you will often find
that
the towel rail is in series with the supply to the HW taps.

I have always assumed that this only works in systems where the hot
water is
recirculated. Is that right?

It can be I guess, but in summer the radator gets hot by the draw off of
DHW not by any pumps.

In our house we circulate the hot water summer and winter, as one or two of
the taps are a long and convoluted pipe run from the hot water cylinder. In
a block of flats they would _have_ to do that.