750mv vs 12v Thermostat Question UPDATE 2
Updated 29 Nov-- Update 2--29 Nov: got it to work. Not clear on the thermostat voltage for these things whether I can use the cheaper version or what. I want it for my furnace only set-up in the R...
Forum Discussion
What has been missed here is that the real reason for knowing whether a thermostat is using 750mV or 24V is to make the anticipator work correctly.
The anticipator is what keeps the heater from running until it actually senses the set point temperature. This uses the current in the sensor circuit to try to duplicate what is happening in the heated space. Some thermostats have an internal control that you can set for this current. Many modern thermostats don't need this because they watch a few cycles and adjust as needed.
So, if the circuit current is different than expected, the heater may run longer than needed or short cycle. Neither of these is a killer.
Matt
The anticipator is what keeps the heater from running until it actually senses the set point temperature. This uses the current in the sensor circuit to try to duplicate what is happening in the heated space. Some thermostats have an internal control that you can set for this current. Many modern thermostats don't need this because they watch a few cycles and adjust as needed.
So, if the circuit current is different than expected, the heater may run longer than needed or short cycle. Neither of these is a killer.
Matt
