titleist1 wrote:i would like to use a digital rather than the bi-metallic slider that i am using with my mag stoker, but the ones i have looked at all require 24V power from the furnace circuit which i don't have. i measured the voltage coming off the harman controller at 7 v. it wouldn't even need to be programmable, i was looking at the RTH111B, but even that says it works off the 24V furnace circuit.
I believe that the voltage is for the relay in the appliance only, so whether its 24v or 7v it shouldn't matter. Although, I wouldn't wire any higher voltage to it than 24v. Try it, or you may want to verify this with a heat installer before you do anything.