When you have a zoned residential heating system, you're able to control the temperature of your home in different rooms or zones independently. This is possible because of dampers in your ducts that open and close in response to thermostat readings. If a problem develops with the damper system, one zone may get too hot or too cold. Here's how to tell if there's a problem with a damper and what can cause a damper to malfunction.

When To Suspect A Damper Problem

When a damper isn't working like it should, a zone has trouble reaching the temperature set on the thermostat. Each zone has its own thermostat so you can control temperatures throughout your house as you like. If a damper doesn't open enough, the zoned area will be too chilly since not enough warm air is circulated through the zone.

If you have trouble controlling the temperature in a single zone, and the rest of your house is heating up properly, it's time to think about problems with the damper.

What Can Affect The Functioning Of The Damper

An automatic damper is controlled by a motor, a thermostat, and the control board of your furnace. If anything goes bad along this pathway, the motor may stop operating the damper. Also, it's possible for a damper to have a mechanical failure where the damper gets stuck or caught on something and is physically unable to move.

How Damper Repairs Are Made

A residential heating service can determine the reason for the malfunction and make repairs. The control panel may display an error code that gives the technician clues about the problem. The thermostat for the zone could be dirty or have bad wiring. There might even be a problem with the furnace control board that keeps it from operating the damper.

A likely suspect for damper problems is the motor that controls it. If parts in the motor, such as the gears, go bad, then the motor won't be able to open and close the damper. When the motor fails, it can be replaced.

A damper is located inside a furnace duct, but the motor is mounted on the outside so it can be reached easily. The old motor can be removed by unscrewing it and pulling it out. Then the new motor can be placed in the same spot and connected to the wiring.

Some damper systems have manual dampers, and those don't have motors. If a manual damper is malfunctioning, it's probably stuck or there's a problem with the lever that moves it. The furnace technician has to figure out why the damper is stuck and repair or replace it so the position of the damper can be adjusted again.