Unit runs but no cooling
Failed compressor, contactor, capacitor or refrigerant loss. We check the whole circuit and confirm airflow before replacing components.
HVAC-02HVAC· Fremont, Alameda County
Rooftop Unit Service in Fremont, CA
Packaged rooftop units are the workhorses of East Bay commercial real estate. Retail centers, warehouses, offices, schools and light industrial buildings depend on them, and they take the full brunt of sun, wind and salt air. We repair, maintain and replace RTUs of every size and configuration: gas/electric, heat pump, cooling-only, single-zone constant volume and multi-zone VAV.
- Sector
- Commercial · Industrial
- Coverage
- Fremont, CA
- Scope
- Repair · PM · Install
- Residential
- Not offered
Our technicians work on rooftops every day. We understand curb adapters, gas piping, roof penetrations, crane logistics and the coordination with your roofing contractor that a clean replacement requires.
Rooftop Unit Service in Fremont
Fremont's warehouses, flex buildings and retail centers are heated and cooled almost entirely by packaged rooftop units. We repair, maintain and replace RTUs from 3 to 100+ tons across Fremont, including economizer repair for Title 24 compliance and curb adapter replacements when equipment lines change.
Fremont facilities include advanced manufacturing and ev/battery production facilities, semiconductor, cleanroom and biotech buildings with process cooling, large distribution and logistics warehouses along i-880 and auto mall parkway and more. See the full Fremont service area page for everything we handle locally.
Scope of work
Rooftop Units / RTUs: what we handle
Equipment
01- Constant volume gas/electric and heat pump RTUs, 3 to 25 tons
- Large VAV rooftop units with VFD-driven supply fans, 25 to 100+ tons
- Units with economizers, power exhaust, hot gas reheat and energy recovery
- Direct-drive and belt-drive blower configurations
- Factory and field-installed DDC controllers integrated with building automation
- Rooftop make-up air and 100% outside air units
Repair & troubleshooting
02- Compressor and refrigerant circuit repair, including multi-circuit units
- Blower motor, belt, pulley, bearing and VFD replacement
- Heat exchanger inspection and gas heat component repair (igniters, inducers, gas valves, pressure switches)
- Economizer actuator, linkage, sensor and controller repair
- Condenser fan motors, contactors, capacitors and control boards
- Cabinet, panel and curb air leakage repairs that waste energy
Maintenance
03- Quarterly or monthly filter service depending on environment and run time
- Belt inspection and replacement, pulley alignment and bearing lubrication
- Condenser coil cleaning to maintain rated capacity
- Economizer testing to confirm damper travel and control sequence
- Heating season start-up: combustion, flame signal and safety checks
- Documented amp draws, pressures and temperatures each visit
Installation & replacement
04- Like-for-like RTU replacements with curb adapters and crane coordination
- Upsizing or reconfiguring units when building use changes
- Energy upgrades: high-efficiency units, VFDs, advanced economizer controls
- Multi-unit replacement programs for property owners on a phased schedule
Diagnostics
Common failures and what they mean
Heating locks out in cold mornings
Dirty flame sensors, failed igniters, cracked heat exchangers or blocked flues. A cracked heat exchanger is a safety issue and requires unit shutdown.
Noise and vibration on the roof
Worn belts, failed bearings, out-of-balance fans or loose panels. Left alone these turn into motor and shaft failures.
High energy bills from an economizer that never closes
The unit conditions 100% outside air year-round. Economizer repair typically pays back within one season.
FAQ
Frequently asked questions
Dispatch
Request rooftop units / rtus in Fremont
Tell us about the facility and the equipment. Attach a nameplate photo if you have one.
Nearby
Rooftop Units / RTUs near Fremont
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