Rooftop Unit Service

Coil work first, because it is where the money is. Condenser coil cleaning restores head pressure and capacity that Valley dust has quietly stolen; evaporator coil and drain pan cleaning restores airflow and prevents overflow. On a plugged rooftop condenser we routinely see head pressures that are shortening the compressor's life every afternoon.

Then the mechanical items that ground-mounted split systems do not have: belt tension and wear on belt-driven blowers, bearing lubrication, blower wheel balance, and economizer damper linkage and actuator operation — a stuck-open economizer pulls 110° outside air into the return all day and nothing about the symptom points at the damper.

Then the standard set, done to spec: refrigerant charge verification, electrical connections tightened, capacitors and contactors checked, safety controls tested, condensate drain and pan cleared, filters changed, and on gas-electric units the full combustion side — burner cleaning, heat exchanger inspection, gas pressure, and CO measurement.

Curb seals and flashing. A rooftop unit sits on a curb, and the seal between the curb and the roof deck is a waterproofing detail that ages in Arizona sun. When it fails, water enters the building at the unit and the leak gets attributed to the roof. We inspect it as part of service because we are already up there.

Cabinet integrity and penetrations: rusted panels, failed gaskets, missing screws, and UV-degraded wire insulation and disconnect boxes. A panel that no longer seats lets monsoon rain into the electrical compartment, which is how a storm turns into a control board failure.

Drainage and pad condition. Rooftop condensate has to leave the roof properly rather than pooling next to the curb, and a pan drain that has been plugged since last summer will find the ceiling below it during the first humid week of July.

Repairs are the same components a ground system fails — capacitors, contactors, motors, boards, gas valves, compressors — with the added variables of roof access, tie-off requirements, and getting parts and tools up safely. We carry the common failure parts so a rooftop no-cool call usually finishes in one trip.

Replacement is where rooftop work differs most. A rooftop unit swap involves matching or adapting to the existing curb, new flashing and sealing, sometimes a curb adapter when the footprint changes, and crane or hoist logistics with the timing and street or lot access that requires. We plan that before quoting, so the price does not change once the crane is booked.

For businesses we schedule around operating hours where the situation allows, and for multi-unit roofs we inventory every unit with its age, model, and condition so you have a written replacement plan instead of a surprise every summer.