In article ,
andrew writes:
Andrew Gabriel wrote:

In article ,
Grimly Curmudgeon writes:
On Tue, 15 Nov 2011 23:48:08 +0000, andrew
wrote:

BN Thermic are in Crawley and I've been wondering about asking
them if I could use the stuff inside the pipe with a termination coming
out of a Plasson Tee.

In principle, there's nothing to stop you using some heatproof flex
and regulating a LV current down it sufficient to raise conductor
temperature, but well within the insulation specs.
Somebody here posted such a thing last winter, but I unrecall the
details.

I made one for the condensate pipework from a dehumidifier many
years ago. It used sleeved constantin resistance wire actually
threaded inside the pipe. That would also work well for a
condensing boiler.

The thing about this stuff is that is two conductors with a resistance
material between them, so the power consumption per unit length is
independent of the length. Its temperature coefficient is such that its
resistance increases faster as the temperature rises.

I just used a froststat, positioned outdoors near the pipework.

--
Andrew Gabriel
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