On 04/26/2017 7:39 PM, Jim Wilkins wrote:
....

These made accurate mechanical thermostats obsolete:
https://www.amazon.com/AGPtek-Digita.../dp/B00BVWYH5A

https://goo.gl/f7e2Np is another alternative. I used one to put an
alarm in the well house if temp drops after the weekend last winter we
were -14F and the gas heater went out and froze up the pressure tank.
Took most of a day and a half to thaw it out; fortunately nothing broke.

I've got it on a wall-wart at the moment but it could easily run off
battery for ages and a small rechargeable w/ solar or the like could
make it independent...

I figured the C/F thingie would be easily done in the setup but these
are C only; I've seen datasteet for the same board but with the display
in F altho I couldn't find a link quickly today. When I looked just for
curiosity last January, seemed like they were going for $10-12/ea
whereas these are essentially throwaways at $3 or so with, some anyway,
free shipping to boot...

Works as advertised...all I added was a regulator as the power supply I
robbed was a little "hot" and noisy altho it ran directly off that
supply figured for long-term duty would be better to clean it up just a
little. I'm just driving the LED that can see from the house at night
if temp drops; add an interposing relay if need more current draw than
the onboard will supply but iirc it'll handle a fair load on its own.

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