A clothes dryer is considered a must-have appliance in most of today's homes. While clotheslines and fresh air remain one of the best methods for drying wet clothes, many households don't have the time or space to use a clothesline. The home clothes dryer that most of us are familiar with is fueled by electricity, natural gas or propane gas and works by pulling in air, heating the air, and then discharging moisture. The discharged air is full of moisture so it is sent through an airtight hose to a rigid vent placed in a wall and expelled outside.
But there is another kind of clothes dryer that can be used indoors, particularly in small spaces: a ventless dryer.
How Do Ventless Dryers Work?
When you shop for a clothes dryer, there are two types of ventless clothes dryers that have no output air vent and rely on other methods to get rid of the heated moisture-laden air: condensation dryers and heat pump dryers. Ventless dryers can be placed in any location in the home and do not require the installation of a vent pipe; making them perfect for renters and small spaces. All ventless dryers are powered by electricity due to the combustible nature of gases in a non-vented space.
Like a traditional vented dryer, the condensation dryer pulls in cool, dry air from the room. The air is heated and passed through the clothes; but instead of being vented outside, the air travels through a cooling device or heat exchanger. The heat exchanger cools the heated air causing the moisture in the air to condense and flow into a containment chamber within the dryer. As the air is dried, it is reheated and passed through the clothes again. The process is repeated until the clothes are dry.
Some models allow the water to be directed and discharged through a clothes washer's drainpipe. This is convenient if you can locate the dryer directly next to the washer or stack the two units. A condenser unit with a discharge unit needs the same attention as one with a containment chamber except for emptying the chamber.
Heat Pump Dryers
A heat pump dryer pulls air from the room. The air is passed through a heat pump where the cold side condenses the water vapor into either a drain pipe or a collection tank and the hot side reheats the air to use again. Heat pump dryers use less than half the energy required by either condensation or traditional dryers.
How to Use and Maintain a Ventless Dryer
Just as with a vented dryer, there are maintenance steps that should be taken with a ventless dryer. If the maintenance is not done, the dryer must work harder to dry clothes and will not last as long as it should.
After EVERY load, the containment chamber must be emptied and the dryer lint trap cleaned to be sure that no debris or lint is clogging pipes. The water that is collected can be recycled to water indoor plants or gardens.
Most lint traps are located just inside the dryer door. After every load, remove the trap and scrape away the lint. Once every two weeks or so, the lint trap should be washed with a bit of dishwashing soap and cleaned with a soft brush to remove any build-up from dryer sheets, fabric softener or detergent.
No matter how diligent you are about emptying and cleaning the lint trap, eventually, lint will accumulate on the condenser unit of the dryer. The unit should be checked and cleaned at least four times per year. If the condenser is covered with lint, it will reduce the efficiency and longevity of the dryer.
To clean the condenser unit, remove it from the dryer and take it outside or to a large utility sink. Using a hose or strong flow of water, rinse each side of the unit to remove any lint build-up that may be inside. Allow the unit to air dry until no water is visible or caught in the unit then return it to the dryer.
While a condenser dryer does not need an outside vent, they do require adequate airflow to operate properly. If they are housed in a closet, the door should be open during drying cycles. It is also important to vacuum regularly behind and around the unit to keep excessive dust at bay.
Prices range from unit to unit, but in general, condenser dryers tend to be slightly more expensive than vented dryers. They also use more electricity to run their extra components, which can add to the cost over time, which is why it is important to keep them well-maintained.
Weaver, Stanton. Energy Efficient Clothes Dryer With IR Heating and Electrostatic Precipitator. No. DOE-GE-06720. GE Global Research, Niskayuna, NY (United States), 2017.