Last updated: April 23, 2026
Commercial HVAC service in San Diego County ranges from a $149 service call to a $25,000 rooftop unit replacement on a larger building. Most repair calls land well under $2,500. A full RTU replacement is the big-ticket item, priced by tonnage, and maintenance contracts are priced by square footage rather than a flat rate.
Bonita is unincorporated, so permits route through the County of San Diego. Bonita Country Estates and the equestrian-property residential along the Sweetwater River valley run larger 1970s-90s estate homes now hitting their replacement window, typically justifying premium multi-zone equipment over a basic swap. Mid-range inland heat here, 90 to 100 degrees common, is less extreme than El Cajon or Santee but still meaningfully warmer than the coast.
South Bay commercial HVAC covers Chula Vista retail, offices, and medical space, priced at the county standard, with night and weekend service available on contract customers who can't take equipment down during business hours.
| Item | Typical cost | Notes |
|---|---|---|
| Commercial service visit | From $149 | Diagnostic and minor repair on rooftop or packaged units |
| Rooftop unit (RTU) repair | $400 - $2,500 | Most common repair range, covers motors, boards, and refrigerant work |
| RTU replacement, 3 to 5 ton | $8,000 - $18,000 | Typical for a small retail space or office suite |
| RTU replacement, 7.5 to 10 ton | $15,000 - $25,000 | Typical for a larger retail, restaurant, or warehouse space |
| Preventive maintenance contract | Priced by square footage | Quoted per building, not a flat per-unit rate |
| After-hours or weekend service call | Standard rate | Scheduled around your business hours, no separate overtime surcharge |
Ranges reflect Bonita and South County San Diego. Your exact figure depends on the factors below. We quote flat-rate before starting.
A preventive maintenance contract catches most rooftop unit failures before they turn into an emergency call during business hours, and it's priced by square footage so a small suite doesn't pay the same rate as a large warehouse. SDG&E offers commercial rebate programs for high-efficiency RTU replacements, and those figures depend on tonnage and efficiency tier, so we confirm the real number for your building rather than quoting one up front.
For a 2,200 to 3,500 square foot Bonita estate home, expect $16,000 to $28,000 for a variable-speed heat pump replacement with two-zone control and smart thermostat integration. Larger equestrian properties with guesthouses or detached structures on the same parcel sometimes add a second smaller system, which adds to the total but keeps each zone properly sized rather than oversizing one system to cover everything.
South Bay commercial HVAC covers Chula Vista retail, offices, and medical space, priced at the county standard, with night and weekend service available on contract customers who can't take equipment down during business hours.
A service call starts at $149. Most repairs run $400 to $2,500. A full rooftop unit replacement runs $8,000 to $25,000 depending on tonnage, with larger buildings needing multiple units.
Yes, for most property owners and businesses. A maintenance contract is priced by square footage and catches problems during a scheduled visit instead of an emergency call that disrupts business hours.
A standard service visit at $149 covers diagnostics and minor adjustments. Most straightforward repairs, like a failed contactor or a refrigerant top-off, stay under $1,000.
A full rooftop unit replacement is the largest expense, running $8,000 to $25,000 depending on tonnage. Buildings with multiple RTUs sometimes replace them in phases to spread out the cost.
Flat-rate pricing, confirmed before any work starts. Same-day scheduling on most calls.