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Commercial Rooftop Units
Package units on light-commercial buildings
A rooftop unit is a different job from a house call
A rooftop package unit puts the compressor, coil, and blower all in one cabinet on the roof, unlike a split system where the compressor sits outside at grade and the air handler sits somewhere inside the building. That single difference changes almost everything about the job. The unit sits on a curb built to the roof's own dimensions, sealed with flashing so the roof stays watertight around it, and ductwork drops straight down through the curb into the building below instead of running across a yard. Belt driven blowers move higher static pressure than the direct drive blower in a typical house system, which is what lets one rooftop unit push air through a longer commercial duct run. Economisers, when the building has one, bring in outside air automatically instead of running the compressor every time the space needs cooling, a real energy saver on the right building and the wrong choice on others.
Why the lift and the crew matter as much as the equipment
A rooftop changeout is not a job you improvise with whatever ladder happens to be on the truck. Roof access, a crane or a lift rated for the unit's weight, and enough crew to set a package unit on a curb safely all have to be lined up before the old equipment even comes off. We have worked an opened American Standard package unit on a commercial roof and set twin condensers on a metal roof, real jobs on real buildings, not a first attempt at this type of work.
Being open 24 hours matters more for a business than a house. A rooftop changeout or an emergency repair can happen before opening or after close instead of during the hours the shop or office needs to stay running.
OUTSIDE TRADING HOURS
A shop or office cannot just close for three days
A house can usually go a day without air conditioning. A shop, a restaurant kitchen, or an office with employees and customers in the building cannot, and closing the doors for the length of a rooftop changeout is rarely a real option. Scheduling that kind of work overnight or across a weekend keeps the building open during the hours it actually needs to be, and it is one of the clearest reasons a 24 hour crew matters more for commercial work than it does for a house call. Roof access itself is its own planning problem before a single wrench turns, ladder placement, whether the unit needs a crane or a lift to get onto the roof at all, and how much clear space the crew has to work in once they are up there.
A full commercial system replacement is covered in more depth on our HVAC system installation page, and keeping rooftop equipment out of trouble in the first place is what our preventive maintenance page covers. To talk through roof access, lift requirements, or scheduling around your building's hours, reach us through our contact page.