EcoRenovator - View Single Post - DIY thermal differential controller (solar hot water pump controller)

Xringer · 11-28-09, 09:29 AM

I wonder if the thermistor could be removed from a modern Tstat
(like the RTH221B1000)

Honeywell at Lowe's: 1-Week Basic Programmable Thermostat

And re-connected using a twisted-pair?

If you could locate the thermistor inside the warm-air collector, the Tstat
could be used in the AC mode. Coming on whenever the temperature
inside the collector got above ~75-85 deg..
I think these things have about three degrees of Hysteresis..
So the fan was moving a lot of air, it would shut down pretty quickly,
as the collector cooled off a bit.

~~
In the early evening, you could try using the heating mode. If the outdoor temp
dropped below 70, air from the house would be sucked into the collector
and cooled down a little.. (Assuming the house was still warm).

11-28-09, 09:29 AM	#31
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	remote thermistor? I wonder if the thermistor could be removed from a modern Tstat (like the RTH221B1000) Honeywell at Lowe's: 1-Week Basic Programmable Thermostat And re-connected using a twisted-pair? If you could locate the thermistor inside the warm-air collector, the Tstat could be used in the AC mode. Coming on whenever the temperature inside the collector got above ~75-85 deg.. I think these things have about three degrees of Hysteresis.. So the fan was moving a lot of air, it would shut down pretty quickly, as the collector cooled off a bit. ~~ In the early evening, you could try using the heating mode. If the outdoor temp dropped below 70, air from the house would be sucked into the collector and cooled down a little.. (Assuming the house was still warm).