Dear Jim: I heard that bugs and mice get indoors through clothes dryer vents. Our outdoor vent flap does not seal well and I can hear wind whistle through it. What vent design is best and how do I stop bugs and mice? -- Ann N.Dear Ann: Insects and mice are the least of your problems with a leaky dryer vent flapper. All year long, air leakage through most dryer vents can really drive up your utility bills. In addition to insects and mice, many allergens like dust, pollen and mold spores flow indoors.
The best sealing outdoor dryer vents use a floating cap design. This looks like a small vertical canister against your outdoor wall. The tough ABS plastic (used for golf club heads) shell can be painted to match your house wall.
When the dryer starts, a lightweight plastic sealing cap floats up from the pressure. As soon as the dryer stops, the cap settles back down. All of the internal parts are made of very smooth plastic to minimize lint buildup.
Several companies also make draft sealer kits that mount indoors where the flexible dryer vent attaches to the outdoor duct stub. These kits have an extra pivoting flapper inside. You can still use a vent flapper outdoors (multiple louver designs are most effective) and cover it with a rodent guard.
If you want to vent your electric dryer indoors in the winter to save energy (check your local codes about this), use one of the indoor/outdoor vent kits with an easy switch handle. These have high-quality lint filters. Clean them often. Also, watch for any excessive moisture buildup or window condensation.
The dryer vent may not be the only source of the insects, mice, etc. There are many hidden access spots which require an inspection to find. Many homes have mice in residence even though you never see them. If your kitchen floor is always crumb-free by the morning, you probably have mice.
Tiny electronic insect/rodent repellers can help. Many of these low-cost units plug directly into a wall outlet. They emit safe ultrasonic sound waves. Better models produce sweep frequencies to repel a greater range of pests without their becoming accustomed to it. These units use very little electricity.
The plug-in rodent repeller that I use does not bother my old cat Ralph, but it obviously is not advised if you have pet hamsters or gerbils. You will really see them run in that wheel then.
For smaller areas, like a closet, battery-operated models are available. One model, called the MothContro, also includes a light with a convenient touch-on switch. The light is powered by two AA batteries and the ultrasonic moth repeller is powered by one 9-volt battery.
Write for (or instantly download -- www.dulley.com Update Bulletin No. 488 -- list of the best-sealing dryer vent kits, electronic insect and rodent repellers, coverage area, product details and dryer efficiency tips. Please include $3 and a business-size SAE.
James Dulley, Deseret News, 6906 Royalgreen Drive, Cincinnati, OH 45244
Dear Jim: We have ceiling paddle fans in three of our rooms. I know in the winter that I should flip the switch so that they blow upward, not down. What speed should I run them in the winter? -- Mike H.
Dear Mike: A ceiling fan can be an energy saver year-round, especially if your home has forced-air heat. By reversing the blade rotation, the warmest air at the ceiling flows out to walls and down to the floor.
In the winter, you should either run it on low or medium speed, but never on high speed. You want it to move as much heated air as possible from the ceiling to the floor without creating a noticeable draft.
James Dulley's Web site (www.dulley.com) includes 150 of his previous columns and illustrations organized under 30 general topics. Dulley's Web site also includes a rush order form for readers who want to expedite the delivery of the current Dulley Update Bulletin offered in his column. Each of the 150 columns also has a related detailed Update Bulletin available for interested readers.