On Sun, 17 Dec 2017 12:17:54 -0800, Dave Nadler wrote:

On Sunday, December 17, 2017 at 3:15:03 PM UTC-5,
wrote:
(old) Cambridge varios used 2 thermistors in line to sense flow.

IIRC 3 thermistors; Raouf added a non-sensing thermistor in the middle
to increase temperature differential. Earlier units like Crossfell used
2.

Thanks: effectively a hot wire solution, then, with the centre thermistor
serving as the hot wire.

I presume the two-thermistor was effectively the same, i.e. pushing
current through both thermistors and relying on the upstream thermistor
to warm the air before it reached the downstream one.


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