Miller manufactures high-efficiency furnaces pleasing to the eye as well as durable. They have many features that add value to the unit, such as a pilot system that eliminates any outages and shuts down automatically if an outage occurs. However, all home appliances and heating systems will develop problems and glitches at some point, and the Miller furnace is no exception. There are a number of troubleshooting steps you can run through before calling a service technician.
Check to see whether the thermostat is set too low or not working if the furnace does not heat up. It should be set higher than the room temperature. Inspect the electrical box for broken fuses or tripped breakers. Reset the breaker if necessary, and replace any broken fuses with another fuse of the same amperage.
Check whether the pilot light has gone out and needs to be re-lit. Follow the lighting instructions attached to the pilot grate door if your furnace has an electronic ignition button.
Check the air filter and gas burners for any blockages or dirt. Replace the air filter if necessary.
Lubricate the blower motor ports (at either side of the shaft) if the furnace switches on and off too quickly. Place a finger on the belt to check for correct tension. It should not depress any more than 1 inch at the center of the belt. Tighten the belt if needed.
Check the gas vent pipes (leading to the outside of the residence) for any blockages or obstructions. A blockage could cause the unit to shut off.