Troubleshooting Your Programmable Thermostat

Aside from investing in a new energy-efficient HVAC system, a programmable thermostat can be the best investment you can make to lower your home’s utility bills. Once you set it, it’s automatic — but what if it isn’t? New technology is great when it works right, and can be frustrating when it doesn’t. But don’t give up and go back to an old-school dial thermostat! Here are a few common things that can go wrong, so you can troubleshoot your malfunctioning programmable thermostat and once again “set it and forget it.”

Low Batteries

The most common reason for a blank or erratic screen on a thermostat is that the batteries need to be replaced. Some thermostats display “low battery” on the screen, but this is the first thing you should check.

Tripped Circuit Breaker 

If your thermostat is wired into your home’s electrical system, check your fuse box for a tripped breaker. Also, many programmable thermostats have a fuse inside the unit. Remove this and see if the filament inside is broken. If it is, take the fuse to a hardware store to buy a matching replacement.

Dirt Inside the Thermostat

If your programmable thermostat used to maintain the correct room temperature, chances are it needs cleaning. Dust and dirt can build up inside the unit and interfere with its operation. Remove the front panel and clean inside with a small, soft brush.

Location of the Thermostat

If it’s never worked quite right at keeping your home the desired temperature, you need to consider the thermostat’s location. A programmable thermostat should be installed away from direct sunlight, doors, windows, or appliances. The best place is in a central part of the home near the HVAC system’s air intake.

Thermostat Needs Reprogramming


Another reason why the setting may not match your room temperature is that the thermostat needs to be reprogrammed — especially when seasons change. If the heat doesn’t come on when the weather turns cold, make sure it’s set to do so. When you’re ready to turn the air conditioning on in the spring, you will need to program it again.

Problems With the HVAC System

There’s a possibility that the problem is not caused by the thermostat, but the HVAC system it controls. When did you last have it serviced? Having your furnace, air conditioner or heat pump inspected and tuned up twice a year keeps it in top condition and can even extend the life of the unit.

Thermostat Needs Replacing

Your programmable thermostat may have stopped working properly due to age, damage or a manufacturer’s defect. In that case, replacing it may be the only way to solve the problem. Call your HVAC professional for an appointment so they can test the thermostat to see if it is repairable. They will also advise you on the best new thermostat for your system.

Programmable thermostats range from basic models to units that are part of a “smart home” system, and new features are added regularly. This usually makes its daily operation simpler, but can cause headaches when things aren’t working right. Your HVAC technician can quickly get to the root of the problem and give you back your preprogrammed, comfortable home.