By James Dulley, Published November 02 2012
Sensible Home: Automatic vent fans most efficient
– Steve R.
Dear Steve: There are several reasons your old bathroom vent fan has gotten louder. Most likely, the bearings in the motor are worn. A good indication of this is if you hear the speed of the fan varying or you hear a slight squealing sound after it runs for a while.
Another possible cause of the noise may just be accumulated dirt or some mounting screws that have come loose. Pop off the grill cover and unplug the fan and light. Clean it out, tighten all the screws and see if that reduces the noise to an acceptable level.
If the noise level is not better, you can replace the entire unit or just replace the motor/fan with a rebuilding kit to get it back to its original noise level. Installing a rebuilding kit is a lower-cost option, but installing a new high-tech vent fan is more efficient and quiet.
The sound level of bathroom vent fans is measured in “sones.” The sones rating should be shown on the packaging. The best new fans create only 0.3 sones, which is difficult to hear running. A smaller capacity fan also is quieter than a large one. A venting air flow capacity of 1.1 cubic feet per minute per square foot of floor area is adequate.
Whenever you are heating or air conditioning, it is more efficient to use a bathroom vent fan than just opening a bathroom window. You have very little control over the amount of ventilation from a window. Also, it may not vent out the excess humidity or odors if the wind is not blowing in the proper direction.
The most efficient type of bathroom vent fan uses some type of automatic control to turn it on and off and control the speed on multispeed models. Particularly if there are children in your family, bathroom vent fans tend to get turned on and left on until an adult finds it running.
A quiet bathroom vent fan with a motion sensor is idea for the area with the toilet. The fan automatically comes on when the sensor detects someone coming into the bathroom. Once the person leaves the room and no more motion is detected, the fan stops after an adjustable length of time.
For bathroom areas that are predominately used for bathing, a humidity-sensing vent fan is best. The most sophisticated sensors, as on the Broan Ultra Sense models, measure the rate of humidity level increase, not just a predetermined humidity level, to switch the fan on.
This reduces the amount of time the fan runs for adequate ventilation and, therefore, saves energy. Another efficient, quiet option is a combination recessed light/vent fan mounted in the ceiling of the actual shower area.
The following companies offer bathroom venting products: Broan/Nutone, (800) 558-1711, www.broan.com; Continental Fan, (800) 779-4021, www.continentalfan.com; Fantech, (800) 747-1762, www.fantech.net; Hunter, (888) 830-1326, www.hunterfan.com; and Panasonic, and (800) 211-7262, www.panasonic.com.
Dear Jim: We have a wood-burning fireplace in our living room. I close the chimney damper when there is no fire, but it does not operate smoothly. How can I tell if it is closing properly and blocking air leakage? – Denise N.
Dear Denise: Old sticky chimney dampers rarely seal well. Several indicators of leaks are a smoky odor when there is no fire, a chilly draft near the fireplace, flying insects near it, etc.
The air leakage past the damper can be either up or down depending upon outdoor temperature and wind direction. Hold a stick of lighted incense in the fireplace opening and observe the smoke trail to detect leaks. Test it several times under various weather conditions.
Send inquiries to James Dulley, The Forum of Fargo-Moorhead, 6906 Royalgreen Drive, Cincinnati, OH 45244 or visit www.dulley.com.