Gas and Oil Home Heating Furnaces - replacing the voltage regulator to the thermostat

I have a thermostat that has an LCD display that shows the time and permits programming.

Over the past months the batteries that provide low voltage to this thermostat to run the clock, etc., have been going bad every other 4 or 5 days.

This results in the cooling/AC not turning on automatically.

I think the voltage regulator that provides low voltage to the thermostat is bad and thus the batteries are providing power and thus running down.

Does this makes sense and if so, how do I replace this voltage regulator???

does not appear to be your problem. the 24 volt circuit from the furnace does not "mix" with your battery voltage, the battery operates the clock, program, digital thermometer, lights, etc. it sounds to me as if the tstat is going bad, a short in the circuit the battery runs, bleeding off the batteries. i would change the thermostat. there really is no "regulator" per say, the transformer provides control circuit voltage which the tstat only opens and closes switches for. if the transformer is bad, you will get no operation of the unit, as control circuits will be de-energized, if voltage is low for some reason, relays will chatter. my money is on the tstat.

Great information and much appreciated......