Portable cooling is rented by the ton and by the week, not bought. A 1 to 2 ton spot cooler on 115V typically runs $150 to $400 a week, a 3 to 5 ton unit on 208/230V single or three phase runs roughly $350 to $900 a week or $900 to $1,800 a month. The size you need follows the heat load in the room, and the power available usually decides it for you.
Tonnage, not room size, decides the machine
Cooling is rented against a heat load: people, lighting, machinery, solar gain through glass and any process running in the space. A server room with four racks and a warehouse mezzanine of the same floor area need very different tonnage. One ton removes 12,000 BTU per hour. Yards will size from a short list of questions, and an undersized unit simply runs all day without ever holding a setpoint.
Where the hot air goes is half the job
A portable air conditioner is a heat pump with the condenser inside the room, so it makes more heat than it removes unless the exhaust is ducted somewhere else. Above a suspended ceiling, out a window kit or into a duct run all work; venting into the same room does not. Ask the yard to send the ducting, the condensate pump and the window or ceiling kit with the unit.
Check the power before you book
A 1 ton unit will run on a 115V 15 amp circuit. Anything from 3 tons up wants a dedicated 208/230V supply, and a 5 ton machine often needs three phase and a specific plug configuration. Tell the yard the voltage, the phase and the receptacle you have. Where the supply is short the rental becomes a cooler plus a generator or a spider box.
Emergency hire and what it adds
Climate hire spikes in heat waves and after a rooftop unit fails, and yards ration the fleet by whoever books first. Same-day or after-hours delivery typically adds a callout charge on top of the standard freight, and peak-season stock may come from a branch further out with the extra mileage billed. A standing purchase order agreed before summer is what keeps you at the front of that queue.
Questions people ask about commercial portable air conditioner rental
How many tons of portable cooling do I need?
As a very rough starting point, allow one ton per 400 square feet of ordinary office space, then add for equipment load, glazing and headcount. Server and process rooms are usually load-driven and need a real calculation, which the rental company will do from your figures.
Can a spot cooler run without a window?
Yes. Most commercial units are supplied with ceiling ducting kits so the condenser air can be dumped above a suspended ceiling or into a return plenum. What it cannot do is exhaust into the space it is cooling.
Is portable air conditioning rented by the day?
It is quoted by the week or the month far more often than by the day, because mobilisation is most of the cost. Short emergency hires exist but usually carry a minimum charge of several days.
Who handles the condensate?
Ask for a unit with a built-in pump and a hose run to a drain. A gravity tank has to be emptied, and on a hot, humid week a 5 ton machine will fill it faster than anyone remembers to check it.