Commercial HVAC replacement and installation in Clovis.

Rooftop units condition close to half of all commercial floor area in the country, so most replacement decisions start on a roof that already has a packaged unit on it. The first choice is like-for-like: a new air-conditioning unit with gas heat, on the same curb, with the same services. It is the fastest path and the least engineering, and it carries forward whatever the old unit got wrong.

The second choice is a dual-fuel heat pump unit. It heats with the compressor when that is efficient and falls back to gas when it is not. The third is all-electric. The Department of Energy says heat pump rooftop units are best suited to mild-to-moderate winter heating, and that across most of the West they can carry most or all of the winter heating demand. That makes all-electric a real option here rather than a stretch. What decides it is electrical capacity at the building, the gas line you already have, and what your utility rates do to the operating number.

A rooftop price and a project price are different numbers. Separate the equipment from the work required to land it, power it, and prove it runs. Otherwise a cheap unit hides an expensive roof.

The nameplate on a twenty-year-old rooftop unit tells you what the building needed twenty years ago. Occupancy changed. Lighting changed. Plug loads changed. Sometimes the envelope changed. Replacing to the old tonnage is a guess dressed up as a spec, and it is how a building ends up with a brand-new unit that short-cycles all summer and still cannot hold a back office.

Confirm the load against how the space is used now. That calculation is also what makes the equipment conversation honest, because it fixes the tonnage before anyone shows you a brochure. The Department of Energy's high-performance rooftop specification was written to cut unit energy use by as much as half against the older standard, and more than twenty models now exceed it. That efficiency is only real if the unit is sized for the load it will actually see.

Then check availability early. Equipment availability and contractor familiarity sit on the Department of Energy's own list of factors that decide whether a heat pump rooftop replacement is workable at a given site. A unit that is right on paper and unavailable for months is not the right unit for a building currently running on a failing one.

Two buildings can run identical units and get very different numbers. One sits on the same curb with the same services and an open lot for the crane. The other needs a curb adapter, a panel upgrade, a structural look, and a lift staged around traffic that never stops.

The first visit is not a look at the unit. It is a look at everything the unit depends on. The reviewer should measure the curb, check the framing under it, trace the electrical feed back to the panel and confirm how much spare capacity is actually there, locate the gas line, find the condensate path, and identify the controls the new unit has to talk to. The Department of Energy groups these under infrastructure for a reason: electrical capacity, physical constraints, and gas lines are the three that most often turn a straightforward replacement into a larger project.

Outside, walk the lift. Where does the crane set up, what does it have to reach over, which stalls close, and for how long. Roof access, screen walls, parapets, adjacent equipment, and overhead lines all decide whether the set takes a morning or a weekend.

Then interview the operation. When is the building occupied, what can be down and for how long, which spaces cannot lose conditioning, and who signs off on a night or weekend lift. Those answers change the schedule, and the schedule changes the price.

California building departments treat HVAC work as permit work, and the scope is broader than most owners expect. Published municipal permit guidance in California lists any electrical, plumbing, or mechanical upgrade or repair as permit-required, alongside items like re-roofing. That matters on a rooftop replacement, because one project usually touches all three at once: the mechanical set, the electrical feed, and often condensate or gas.

Confirm the Clovis requirements with the local building department before equipment is ordered, not after it lands. Ask which permits apply, whether plan review is needed, what the inspection sequence looks like, and how a re-roof in the same season should be coordinated with the unit set.

Refrigerant is the first. EPA rules under Section 608 of the Clean Air Act govern how refrigerant is handled and recycled in stationary air conditioning and heat pump equipment, and those rules follow the unit for its whole life, not just installation day. New equipment ships on newer refrigerants, so a building replacing units one at a time will run a mixed fleet for years. Plan the service contract and the spare-parts strategy around that.

Incentives are the second. The Department of Energy publishes guidance on rooftop replacement incentives, and utility programs are one of the factors it names for heat pump rooftop adoption. Programs change and expire. Confirm what is actually open before you commit to an efficiency tier — an incentive that existed two years ago is not a line item until someone verifies it is still funded today.

Most rooftop units get replaced the day they die. The Department of Energy is direct about the cost of that habit: facility managers often delay until the unit no longer conditions the space, needs constant service, or fails outright, and replacing inefficient units proactively is frequently the better business move than replacement-on-failure — or even than a like-for-like swap at the end of service life. A failure in August removes every option except whatever is on a truck.

If your roof carries more than one unit, treat them as a fleet. Rank them by age, run hours, service history, and how much of the building each one serves. Replace in that order, in the shoulder seasons, with load calculations and permits done in advance. The Advanced Rooftop Unit Campaign brought together more than two hundred organizations that upgraded over forty-three thousand units and cut a combined thirty-seven million dollars a year in energy cost. That came from planned programs, not emergencies.

Phasing also lets you buy once for the building. If a panel upgrade or a control platform will serve several future units, doing it during the first replacement usually costs less than mobilizing for it three separate times.

Ask every bidder to price the same tonnage, the same efficiency tier, the same curb work, and the same permit and commissioning scope. If one quote excludes rigging or structural work and another includes it, the totals are not comparable.