The exhaust fan in your kitchen is more important that you might think. Aside from keeping the area “fresh,” by expelling odors, it provides a critical safety function by venting dangerous gases such as propane, and shunting moisture and grease outside the house. Keeping this fan in good repair is about safety as much as convenience. When they fail, it is important to address the issue immediately. Let’s look at some costs associated with this.
No Power to Exhaust Fan
This type of problem is usually diagnosed by an electrician “tracing” the wiring and finding whether a switch, motor, or the wiring itself is faulty. If a fan operates intermittently, the problem is more likely to be in a switch than the motor, and this will be a less expensive fix. If the fan’s motor has failed due to power, an electrician can easily address this issue for $90 to $176.
Strange Noise from Exhaust Fan
Scraping, grinding or humming sounds indicate that your fan has a foreign object in its mechanisms, or is “gummed up” with grease or other substances. In the case of a low hum, it may be an electrical problem with the motor. A new fan is most likely in order – the old one must be removed anyway. Exhaust fans are rated by power consumption and also by their ability to move air, measured in Cubic Feet per Minute (CFM). Ask your electrician which model might be best, and remember there are multi-speed models that have efficient CFM and power ratings which can save energy costs. Replacing one entails removing the old unit, testing the wiring, and installing the new one (possibly involving cutting some ceiling materials). Expect to pay from $97 to $190 for this job.
Many kitchens use high-power appliances such as microwave ovens and ranges which were not in common use when the dwelling was built. At times that these are using a lot of the available power, turning on the exhaust fan will overload the circuit, and cut your electricity. Many times this happens in older homes (built before the 1960s) where the wiring needs upgrading from 40 to 100 amps, for example. Your electrician can address this with an updated breaker, by moving the circuit to a heavy-duty breaker on the same panel, or by installing a more energy-efficient fan model. To address this issue, expect to pay from $156 to $209.
Exhaust Fan Duct Problem
Your fan is attached to a metal duct which serves an important purpose of expelling fumes, gases, odors, grease and moisture outside of the house. These materials can vent into the ceiling cavity and cause serious problems, including a fire hazard (from gas/propane fumes), and providing food for insects or other pests (with grease). Moisture may also cause your ceiling to warp or discolor over time. If you hear a metallic rattling sound, consider having the ducting inspected and repaired. It may be a good time to replace the fan then as well, as it must be removed to get to the ducting. For duct repairs, budget $114 to $236. TIP: Ask your contractor to use screws instead of nails where possible when installing duct hardware, as these are less likely to loosen due to moisture over time.
Exhaust Fan Not Stationary
If your fan’s mounting hardware has loosened as described above, you may hear or see vibrations from your fan assembly. Recall that moisture will often lead to such problems, so ask an installer about ways to better mount and seal your fan to avoid wood and ceiling materials from warping, shrinking or swelling. Any of these situations can cause gases and grease to vent into your ceiling instead of the duct. As before, consider replacing the fan with a new model when doing such repairs. Your installer can redo your mounting hardware and replace the fan for $93 to $132 in most instances.