All-in-One Washer Dryer: How Combo Units Work
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An all-in-one washer dryer washes a load and then dries it in the same drum, with no second machine and no transfer between them. It suits some homes far better than others. This guide explains how a combo unit works, what it needs to install, and when a separate pair is still the better choice.
What an all-in-one washer dryer is
A combo unit is a front-load washer with a dryer built into the same cabinet and drum. After the wash and spin, the drum turns again while the unit heats and dries the load. Many combo units dry with a heat pump: they recirculate warm air, condense the moisture out and drain it away with the wash water, so the unit does not vent outdoors. The LG and Samsung models below are both ventless; each maker's page lists its vent type.
All-in-one or a stackable pair
A stacked pair is two machines, so you can wash one load while the last one dries. A combo unit runs one load at a time from wash to dry, and it needs no vent and no stacking kit. If your household runs several loads back to back, a pair keeps up better; if you want one appliance that finishes a load while you are out, a combo fits. Our stackable washer and dryer guide covers the two-machine option.
Cycle times and capacity
Makers list the drum capacity on each model page, and some also state the length of the fastest combined wash and dry cycle. Both vary by model. A full wash and dry in one drum takes longer than a wash in a dedicated washer, because the dry happens in the same drum afterward. Compare the figures on the maker's page for the exact model rather than a general number.
Installation: water, drain and power, no vent
A combo unit needs a cold or hot and cold water supply, a drain and an outlet. Because the dryer does not vent outdoors, it can go where a vent run is hard or impossible to add. Check the electrical requirement on the spec sheet, since some models are built for a standard 120-volt outlet. Leave the space the maker lists around the cabinet.
Models to compare
These two combo units show how LG and Samsung each approach the format.
Ventless Washer/Dryer Combo LG WashCombo All-in-One 5.0 cu. ft. Mega Capacity with Inverter HeatPump Technology and Direct Drive Motor
Model WM6998HBA
- Washes and dries in one ventless unit.
- Inverter HeatPump technology, per LG.
Bespoke AI All-in-One Ventless Combo
Model WD53DBA900HBA1
- 5.3 cu. ft. capacity, per Samsung.
- Ventless, with AI OptiWash and Dry.
Who should buy a separate pair instead
- Households that run several loads in a row, since a pair washes and dries two loads at once.
- Homes that already have a vent and a 240-volt or gas dryer hookup in place.
- Anyone who wants the largest drum capacity on the dryer side.
Next steps in the Sacramento area
Bring a photo of the space, its water and drain hookups and the outlet to the Roseville showroom, and our team will check the makers' installation requirements with you. Our washers and dryers page covers every laundry format.
Frequently asked questions
How long does an all-in-one washer dryer take to dry?
It depends on the model and the load. Where a maker states its fastest combined wash and dry cycle, it is on the model page, sometimes with a note that cycle time varies by load. Check the model page for any unit you are considering.
Do combo units need a vent?
A heat-pump combo unit does not vent outdoors. It condenses the moisture out of the air and drains it away.
Can an all-in-one go in a closet?
Often, because there is no vent run. LG's spec sheet for the WM6998HBA says a closet with a door needs an upper and a lower vent opening to prevent heat and moisture buildup, so check the space and the closet ventilation the maker lists, and confirm the water, drain and outlet are in place.
Do they use a regular outlet?
Some models are built for a standard 120-volt outlet. The spec sheet for the exact model states its electrical requirement.
Does an all-in-one washer dryer fit a small space?
It can, and the measurements decide it. LG lists its WM6998HBA at 27 inches wide, 39 inches high and 33 1/8 inches deep, with a ventless design that LG says allows installation in locations without external vent access, and an electrical requirement of 120 volts, 12 amps. LG also lists a depth of 57 3/4 inches with the door open, so plan the space in front of the unit as well as its footprint. Measure your space against the spec sheet for any other model you consider.
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