> SHORT:
>=20
> I want a valve functionally equivalent to a car's "thermostat" as used in
> vehicle radiator system but MUCH smaller.
> Use is temperature regulation of a low volume flow.
> (Somewhere in 0.1 cc /s  - 5 cc/s range). (eg may be 0.1 - 1 or 1-5 etc) =
tbd
> Some leakage bearable as long as << min flow rate
>=20
> Temperature entering valve rises when flow restricted.
> Temperature entering valve falls when flow occurs.
> Time constants ideally < to << a few seconds
>=20
> Could be :
>=20
> - Electrically controlled (solenoid etc) with external temperature sensin=
g.
> Ideally zero current when not adjusting
> or
> - Mechanical with  no-electrical power - eg bimetallic ...
>=20
> Example solution:
>=20
> A miniature servo with cam constriction of a flexible pipe (a la peristal=
tic
> pump) + electronics would work well.
> Care needed with size, lifetime.  No servo current when temperature is
> stable.

So you are looking for a temperature control valve like fitted to central h=
eating radiators - not common in NZ, but commonly used in the UK?

E.g. http://www.diy.com/search/results/?question=3Dradiator+temp+valve



--=20
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