Spot coolers deliver precision cooling to the rooms, people or servers that need it.
When an air conditioner or HVAC system can’t get the job done, or can’t do it cost-effectively, a spot cooler is the fast, easy, portable solution that can meet your mission-critical cooling needs over the short or long term.
What are spot coolers?
Spot coolers are compact, portable cooling units that deliver targeted cooling to rooms, equipment or people. They roll on casters and plug into a wall outlet, so you can place one exactly where you need it. The cool air can be directed using a swiveling louver. Waste heat is typically ducted out through a window, door or ceiling panel.
Spot coolers remove anywhere from 1 ton to 5 tons of heat per hour depending on the size of the unit. A typical 2-ton spot cooler weighs about 250 pounds, and even 5-ton spot cooler can weigh under 700 pounds.
While the most common type of spot cooler is an air-cooled unit (in which the warm condenser air is vented through a duct), there are other types, including heat pump spot coolers and water-cooled units. Heat pump spot coolers are similar to air-cooled spot coolers but they can produce heat as well as cold air. They must be hardwired by a qualified technician.Water-cooled spot coolers use a water source instead of a condenser to remove hot air. That means there is no condenser air discharge. Water-cooled units work well when there is no good way to duct out waste heat.
Spot coolers are low-maintenance. Moisture from the condenser is collected in a small tank, which needs to be emptied periodically (unless you run a drain line).
Spot cooler applications
Spot coolers can be used for temporary cooling when an HVAC system fails or underperforms. Businesses with critical cooling requirements, such as food purveyors and pharmacies, sometimes need robust emergency cooling on short notice, and spot coolers fit the bill.
But there are countless other applications. Spot coolers can be used to augment existing cooling systems during heat waves or deployed during special events in venues that have no cooling or have insufficient cooling. They can be an excellent choice for server rooms and data centers because cool air can be routed directly to the equipment. “You can get the machine right next to the server,” said Brian Sloat, United Rentals branch manager and climate solutions specialist.
Spot coolers are ideal for targeting specific areas within a much larger space, such as a million-square-foot production facility, that would be impractical to cool in its entirety. “You can literally cool a person on a production line,” said Sloat.
Spot coolers are also the logical choice when a portable air conditioner would require too much ducting.
“If you have to cool, say, the sixth floor of an office building, you could pop out windows and run ducts from a portable air conditioner all the way up, but think about how labor intensive that is,” said Sloat. “And once you get the air in the building, you have to distribute it. If you go with spot coolers, you can pick the offices you want to cool and position them there.” Bonus: When cooling needs change or a workspace moves, you can easily relocate the spot cooler.
Tips for renting a spot cooler
Spot coolers are sized by tonnage. A refrigeration ton is roughly equivalent to 12 000 BTUs and can cool 300 square feet on average. So generally speaking, a two-ton spot cooler can cool about 600 square feet. The actual number depends on the specifics of the space, including the ceiling height, the number of windows and the number of heat-generating people or computers in the room.
In certain situations, it’s smarter to go by cubic feet instead of by square footage. One example is a warehouse stocked with temperature-sensitive items stored on elevated racks.
Your equipment rental provider should be able to recommend the right size spot cooler for your application. To do so, they may need to see the space. For example, said Sloat, “For anything higher than an 8-foot ceiling, you'll want to get somebody to do a job walk.”
It’s important to size your spot cooler correctly. If it’s too small for the space, it may never shut off. “The evaporator coil can freeze up and lead to failure,” said Sloat. “You’ll have to wait for it to defrost, and then you're without an air conditioner again.” A similar problem can occur if you set the thermostat too low; the cooler will never shut off, which can take the unit offline when you need it most.
Sloat warned against self-installation for all but the simplest cooling projects. “Spot coolers are not always as simple as ‘wheel it in and plug it in.’ You can run into problems if you have too many bends in the ductwork, or if you’re cooling a rack that needs open airflow.”
United Rentals can not only help you choose the best spot cooler to rent for your application but also provide expert installation. Visit your local branch or call 800-532-7802.
Dave Johnson is a Los Angeles-based freelance writer who has been writing about all aspects of business and technology since before there was an internet.