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.
Casa de Oro's hillside neighborhoods along the SR-94 corridor run mostly 1970s-80s tract HVAC systems now hitting end of life, and East County's extended summer heat, 95 to 105 degrees common, justifies premium variable-speed equipment that handles the long cooling season efficiently rather than a basic single-stage swap. Permits route through the County of San Diego since Casa de Oro is an unincorporated community.
East County commercial HVAC carries the highest summer cooling loads in the county, and equipment sized for that load costs more on a full rooftop replacement. Maintenance contracts here focus on predictable monthly cost specifically to avoid an emergency repair during a heat event.
| 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 Casa de Oro and East 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.
Generally yes, given how long the cooling season runs in this part of East County. A variable-speed heat pump modulates output rather than cycling on and off at full capacity, which matters when a system is running eight-plus months a year. It typically costs $2,000 to $4,000 more upfront than single-stage equipment but cuts energy use meaningfully over a season this long, often recovering the difference within a few years.
East County commercial HVAC carries the highest summer cooling loads in the county, and equipment sized for that load costs more on a full rooftop replacement. Maintenance contracts here focus on predictable monthly cost specifically to avoid an emergency repair during a heat event.
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.