Commercial HVAC Repair for Rooftop Units and Split Systems
Rooftop unit and commercial AC repair
When a rooftop unit quits on a 100-degree afternoon, the problem isn't just comfort. Customers leave, staff can't work, and in a restaurant the kitchen gets unbearable. We repair commercial heating and air for offices, retail, restaurants, light industrial spaces and apartment buildings, working on rooftop package units, gas packs, heat pumps and split systems. The technician finds the actual failure, explains it in plain terms, and gives you a price before the repair starts.
Why choose Blue Star
Commercial repair calls often come with a history: the same unit has been topped off with refrigerant three summers running, or a contactor keeps burning out. We look for why it keeps failing, not only what failed today. If a unit is near the end of its life, we tell you so, and we can give a repair price and a replacement price side by side so the decision stays yours.
- Compressor and fan diagnosis
- Gas heat section repair
- Refrigerant leak checks
- Economizer and damper repair
- Belts, motors and controls
- Repair vs. replace pricing
Where we work
Rooftop equipment in East County has a harder life than units closer to the Bay. Antioch's July highs average about 91 degrees, with a record of 117, and afternoon Delta wind carries dust and farm debris into condenser coils around Oakley, Brentwood and Discovery Bay. That combination shows up as high head pressure, failed fan motors and tripped compressors. We cover businesses from Wilbur Ave and Railroad Ave west to the Concord and Walnut Creek office corridors along SR-242 and I-680.
Major corridors
- SR-4
- SR-160
- Wilbur Ave
- Railroad Ave
- Sand Creek Rd
- Brentwood Blvd
- SR-242
- I-680
4.9 stars on Google
Read more reviewsColton was great. He found the problem right away and did a temporary fix to get my a/c running until he could get the right part ordered. He also made sure every inside was working well.
Questions we hear
What causes most rooftop unit breakdowns in summer?
In our area, heat and dirty coils are the usual starting point. When the condenser coil is packed with dust and debris, the unit runs at high pressure through 100-degree afternoons, and weak capacitors, contactors and fan motors give out first. Low refrigerant from a slow leak, slipping belts and clogged condensate drains are the other common calls. Most of these are preventable with regular maintenance.
Should I repair or replace an old rooftop unit?
It depends on the unit's age, the repair cost compared with its remaining value, how often it has failed, and whether parts and refrigerant are still easy to get. A unit past roughly 15 years that needs a compressor is usually a replacement candidate, while a newer unit with a failed motor is not. We can price both options so you can compare them before deciding.
Do you repair older units that use R-22 refrigerant?
Yes, we still service R-22 equipment. R-22 is no longer produced, though, and only recovered or reclaimed refrigerant is available, which makes recharges costly. For an R-22 rooftop unit with a significant leak, putting more refrigerant in is often a poor bet. We find the leak, tell you what fixing it involves, and help you decide whether a replacement makes more sense.
Can you work on equipment we did not buy from you?
Yes. We service all brands, regardless of who installed the equipment. Share whatever records you have, such as model and serial numbers or past service reports, and we can often spot a pattern in earlier repairs. If you manage several sites, we keep notes on each unit so the next visit starts with its history instead of from scratch.
What information helps when I call for commercial repair?
The building address, where the equipment sits (roof, side yard or mechanical room), how roof access works, and what the unit is doing, such as blowing warm air, short cycling, tripping a breaker or leaking water. A photo of the unit's nameplate helps us bring the right parts. Also let us know about any access contact, alarm code or tenant schedule we need to work around.
Related services
All servicesBlue Star Heating & Air is just a call away!
Unit down or acting up? Call (925) 584-2428 during business hours with the make, the symptom and where the equipment sits, and we will get a technician scheduled.