I performed a two system heating maintenance. I replaced 1-16x25x1 filter, the media filter was still in good condition and will need to be replaced in cooling maintenance. I checked the amp draw on the blower motor and inducer motor. I cleaned the flame sensors and checked igniters. I checked safeties and confirmed proper sequence of operation. Systems are currently heating at manufacturers specifications. The upstairs thermostat is Going threw cheaper batteries faster then normal. There is nothing wrong with the system to cause this. The thermostat will need to be replaced but is currently operating. Customer is going to install their own non programmable thermostat.