Tight-sealing Dryer Vents
I just noticed when I was outdoors that my dryer vent flapper does not seal well. Are there any high-quality, yet inexpensive ones that seal better? Can I direct the dryer air indoors to save the heat during the winter?—Pat B.
It is very important to install a tight-sealing dryer vent cover for several reasons. The dryer vent duct is a direct open path from inside your house to the outdoors. If the vent cover does not seal well, it is the same as leaving a window partially open and conditioned air can freely exchange from inside your house. This drives up your utility bills year-round.
Other less obvious problems are insects and mice that enter your comfy home through a dryer vent that does not seal well. It may also be a source of pollen and mold spores that aggravate allergic reactions.
There are several kits available with high-quality lint traps for venting an electric dryer indoors during the winter to save heat and humidity (check your local codes about setting up your dryer vent in this fashion). NEVER vent a gas dryer indoors because the products of combustion will stay indoors and the moisture output will be even higher.
Some of the indoor/outdoor kits are designed so you can quickly switch them from venting outdoors to indoors. The dryer stays attached to the outdoor vent and you just flip a lever to switch from outdoors to indoors. Other models have the dryer duct terminate in an indoor filter unit. All the lint trap designs use cleanable filters and some also include a water reservoir to remove more lint. Keep in mind a high concentration of lint in the air can be a fire hazard.
One of the best-sealing types of outdoor dryer vent kits is a floating cap design. This is the design I use in my own home. It is made of heavy-gauge, durable plastic, so it will hold up well to playing children or other impacts should it get bumped.
When your dryer is not running, a plastic sealing cap rests on a seat inside the housing and creates a good seal. When you turn your dryer on, the pressure from the exhaust airflow lifts this lightweight sealing cap off of the seat. This allows the warm, damp air to flow outdoors. The cap continues to float until the dryer stops and then it settles back down on to its seat.
Another good option is a draft sealer kit that mounts inside the house where the vent pipe comes in from outdoors. In this location, the sealing flap is less prone to damage and degradation from the sun and bad weather. It uses a multiple horizontal louver design to save space and to provide adequate airflow.
When using one of these draft sealer kits, you can cover the outdoor vent with a pest/rodent-resistant cover or with another standard vent flapper kit. Since this will create double seals, inspect both areas regularly and clean out any lint buildup. For efficient clothes dryer operation, it is important there is not too much resistance that may impede the dryer airflow.
Check the condition and shape of your flexible dryer vent duct. Position it with gentle curves so there are no sharp bends. Sharp bends create great airflow resistance and they can be areas for lint buildup. If space is limited, install a flat expandable aluminum dryer vent extender and run the flexible duct from it. Using this method, the dryer can be placed only three inches from the wall. Other kits allow you to recess the dryer vent into the wall cavity so the dryer can be placed almost flush against a wall.
