On Fri, 24 Sep 2004 18:48:53 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
Phil Addison wrote:

I meant to add that I find that it helps to get consistent readings
with the IR thermometer if I stick a small square of black PVC tape
on all the flow and return pipes, just below the valves, as a target
for the IR reading. Without that, the reading depends somewhat on the
state of the pipe surface and whether it is painted or not, and
varies according to which bit of pipe you point the meter at. I'm not
sure that black is any better than any other colour in practice,
although in theory black is the ideal colour. The main thing is to
get a consistent emissivity surface to take readings from.

Do you mean ordinary black insulating tape?

Yes

Doesn't it go all goo-ey with the heat?

Dunno... probably. White spirit should clean up any goo.

Do you leave it on, or remove
it immediately after balancing?

It's still on, waiting for that final tweak when I get the round tuits.

Phil
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