I often wonder how normal TRV's can work effectively, as their sensor is so
close to the source of heat.

I have seen old ones like this
http://myweb.tiscali.co.uk/infoweb/TRV.JPG
but usually not in domestic situations.

Does a design with an external vial perform sufficiently better
to make them worth considering, in spite of their aesthetic problems?

--

Graham

%Profound_observation%.

On Sat, 25 Nov 2006 15:58:00 +0000, Graham wrote:

I often wonder how normal TRV's can work effectively, as their sensor is so
close to the source of heat.

I have seen old ones like this
http://myweb.tiscali.co.uk/infoweb/TRV.JPG
but usually not in domestic situations.

Does a design with an external vial perform sufficiently better
to make them worth considering, in spite of their aesthetic problems?

I think the point is that _any_ TRV is a huge improvement over a
non-thermostatic valve. The type in the example you show is usually
specified where the TRV itself is likely to be covered by curtains or
suchlike so as to make it almost completely ineffective.

For a remote sensor to give better control over room temperature it
probably ought to be on the far side of the room. The Honeywell
system with even more aesthetically-challenged motorised TRVs is a
step in this direction.

On Sat, 25 Nov 2006 16:29:30 +0000, John Stumbles wrote:

On Sat, 25 Nov 2006 15:58:00 +0000, Graham wrote:

I often wonder how normal TRV's can work effectively, as their sensor is
so close to the source of heat.

I have seen old ones like this
http://myweb.tiscali.co.uk/infoweb/TRV.JPG but usually not in domestic
situations.

Does a design with an external vial perform sufficiently better to make
them worth considering, in spite of their aesthetic problems?

I think the point is that _any_ TRV is a huge improvement over a
non-thermostatic valve. The type in the example you show is usually
specified where the TRV itself is likely to be covered by curtains or
suchlike so as to make it almost completely ineffective.

For a remote sensor to give better control over room temperature it
probably ought to be on the far side of the room. The Honeywell system
with even more aesthetically-challenged motorised TRVs is a step in this
direction.

================================
Have you got a reference for Honeywell motorised TRVs? I'm interested to
see what they look like and how they work.

Cic.

--
================================
Testing UBUNTU Linux
Everything working so far
================================

The message
from "Graham" contains these words:

Does a design with an external vial perform sufficiently better
to make them worth considering, in spite of their aesthetic problems?

Sod the aesthetics, that would last about five minutes in our house.

--
Skipweasel
Pay no attention to that man behind the curtain.

In article ,
"Graham" writes:
I often wonder how normal TRV's can work effectively, as their sensor is so
close to the source of heat.

I fitted all mine at the bottom, and mostly on the return pipework
(which is cooler). Positioning at the bottom means they are in the
draft towards the bottom of the radiator, and so pretty accurately
reflecting the room temperature. The thermal sensor is also well
insulated from the pipework, so there's no heat conducted to it.
I was also sceptical, but the scheme does seem to work surprisingly
well.

I have seen old ones like this
http://myweb.tiscali.co.uk/infoweb/TRV.JPG
but usually not in domestic situations.

I used the Drayton/Invensys TRV4. The instructions cover the remote
sensor version too (which I didn't use). It says the sensor is
ideally fitted at a height of 1.5m on the wall away from the radiator,
or on the wall under the radiator.

Does a design with an external vial perform sufficiently better
to make them worth considering, in spite of their aesthetic problems?

Also the fragility of the capilliary pipe (probably unsuitable if
small children around). The first 6" of capilliary pipe must not
be clipped as it moves where it enters the valve head.

It probably does work better, but I'm not sure to what extent the
extra accuracy matters. I used to have a proportional control gas
wall heater (Drugasar). That used a vial which suffered from self-
heating. I pulled it out to hang below the heater, and it then
maintained the room accurate to 0.1C (which was the limit I could
measure). Interesting though this accuracy was, it's not something
you can "feel".

--
Andrew Gabriel

On Sat, 25 Nov 2006 17:27:39 +0000, Cicero wrote:

Have you got a reference for Honeywell motorised TRVs? I'm interested to
see what they look like and how they work.

Honeywell's web site?

Mind you I've no more idea where in that tangled web you'll find them.
Last time I looked at their wibbles they were full of broken links from
one part of their own sites to others.