Why Is Your Gas Furnace Making Your Home Too Hot?

Lack of heating is a common concern among homeowners in the winter, but too much heating can be equally problematic. While everyone likes coming home to a cozy, warm home during the cold season, sitting in a sweltering living room is never much fun. Turning your thermostat down might provide a reprieve, but it shouldn't be necessary with a furnace that functions correctly. 

If you can't seem to control the heat in your house, or some rooms are much warmer than others, your heating system may be suffering from one of these three common problems.

1. Thermostat Troubles

A typical residential heating system operates on some fairly straightforward logic. The thermostats in your home monitor the temperature nearby, waiting for it to fall below your setpoint. Once the temperature drops far enough, the thermostat will tell the furnace to cycle on. When the furnace satisfies the thermostat's demands, the heater will shut off again.

A faulty thermostat can interrupt this cycle in numerous ways, such as by preventing the thermostat from accurately reading nearby temperatures. As a result, your thermostat may continue to call for heat long after your home reaches the desired temperature. Fortunately, a trained HVAC technician can quickly and easily diagnose thermostat issues and replace yours if needed.

2. Wiring Issues

Most thermostats use low-voltage control wiring to signal the furnace to turn on and off. Even if your thermostat is operating correctly, a problem with your home's low-voltage control wiring can cause erratic or inconsistent furnace behavior. These issues may cause your furnace to turn on randomly or fail to shut off at the correct time, causing temperatures to skyrocket.

Unfortunately, diagnosing a wiring issue with your heating system is usually more complex than diagnosing a faulty thermostat. Your technician must confirm that your thermostat is operational, check the furnace control board for faults, and then attempt to locate the faulty wiring. While this low-voltage wiring generally does not pose a safety hazard, you still shouldn't ignore any potential faults.

3. Faulty Control Board

Your furnace's control board is the brains behind your heating system, although most control boards perform only a handful of relatively simple duties. Since the furnace relies on the thermostat to call for heat, the primary role of the control board is to step through a checklist of sensors and switches to ensure your furnace operates efficiently and safely.

As with wiring issues, control board issues often result in strange or erratic behavior. For example, you may notice your home being too warm on some days and cold on others. Unfortunately, allowing your furnace to run too long can cause serious issues, including damage to your heat exchanger. If you notice inconsistent and odd behavior, you should contact a professional for an evaluation as soon as you can.

Contact a local HVAC service, such as Turnbull Heating & Air Conditioning, to learn more.