The MC37M is a portable evaporative cooler rated at 3,100 CFM with three fan speeds, a 10.3-gallon tank and a hookup for continuous water. It is built for garages, shop floors and open outdoor spaces rather than living rooms: no thermostat, no app, and a fan that is loud on high. Evaporative cooling also loses most of its effect once humidity climbs above 60 percent.
Full review
3,100 CFM on roughly 250 watts
The draw of an evaporative cooler is the power bill: the MC37M moves 3,100 CFM on roughly 250 watts, a fraction of what a comparable air conditioner pulls for a similar sense of relief. Three fan speeds let the output be dialed back, and the cooling pads are industrial-grade and replaceable rather than sealed in. What comes out is cooled, moistened air, not conditioned air.
A 10.3-gallon tank and a continuous water hookup
The tank holds 10.3 gallons, and a hose connection lets the unit run unattended instead of being refilled by hand every few hours. Caster wheels move the 40 lb chassis easily enough, though they are noisy over rough concrete. Hard water is the maintenance issue to plan for: mineral scale builds on the pads and can clog the pump and the water distribution line if the unit is never flushed.
Above 60 percent humidity it stops doing anything
Evaporative cooling works by making dry air take on water, so the temperature drop shrinks as humidity rises and effectively disappears above 60 percent. In a humid climate this is not a cooler that underperforms, it is the wrong machine. Because it adds moisture indoors, it also needs an open door or window, which is why it belongs in a garage rather than a sealed room.
Loud on high, with no thermostat and no app
The fan is loud at its top speed, loud enough to be a problem in a bedroom or a home office. There is no thermostat, no scheduling and no connectivity; the controls are a panel of switches and a dial. Owners have also reported pumps failing early, which is the component to watch and, fortunately, one of the cheaper ones to replace.
Strengths
- +3,100 CFM cooling capacity for effective room cooling
- +3-speed control for adjustable airflow
- +Portable design with caster wheels for easy mobility
- +Evaporative cooling technology that adds moisture to air
Watch-outs
- −Loses most of its cooling effect once humidity climbs above 60 percent
- −Adds moisture to the air, so it needs an open door or window to work
- −Loud on the top fan speed, with no thermostat, scheduling or app control
- −Hard water leaves mineral scale on the pads and can clog the pump and distribution line
- −Owners have reported pumps failing within the first months of ownership
How it compares
More airflow than the smaller Hessaire MC18M and easier to move than the MC61M, which holds more water and pushes more air. Against a window air conditioner it wins on portability and draws a fraction of the power, but it cannot cool a humid room at all.
Rating sources
Our 4.0 score is the average of these published ratings. Ratings marked * were derived from the reviewer’s written analysis or video transcript — the publisher didn’t print an explicit numeric score, so we inferred one from their own words. Click through to verify. More about methodology.
