Key Issues When Deciding to Rent or Buy Portable Cooling Units
Inevitably, the question of whether to rent or buy temporary, portable cooling equipment comes up at some point in a manager's career. HVAC systems are complex and tend to fail at critical moments. When considering the options, it is important to look at several key issues, including:
- the purchase price of a new or used cooling unit
- the frequency with which a facility might need the unit
- the tolerance of building occupants for limited or no cooling
- the size of the unit to purchase
- whether a manager sees such a unit as a want or a need.
For most managers, the easiest and most common way to solve a portable cooling need is to rent or purchase a DX unit that technicians can wheel into an area and set up quickly.
As a rule of thumb regarding the size of the unit, managers should plan on 1 ton of cooling for every 300-500 square feet of office space, depending upon the use of the building.
Portable coolers can range from a couple of hundred dollars for a unit that can cover a couple of hundred square feet — typically, a 1/2- to 1-ton system — to thousands of dollars for a ground-mounted, ducted system that can provide tens to hundreds of tons of cooling.
In the case of a major renovation or the need for more than one or two small units, it might be more advantageous to consider a larger, ground-mounted system. These systems are typically DX or chilled-water systems situated at ground level. They arrive either on a flatbed truck or as a trailer attached to a truck.
Technicians position the unit, and they run insulated ductwork — which provides return and supply air through a window — up the side of the building to the space that requires cooling.