Seasonal tune-up and full diagnostic on your Carrier, Trane, or Goodman system - readings shown to you before any repair is proposed
Diagnosis first, numbers second - you approve the repair price before a single part goes in.
Fast, Reliable AC Repair Across Cotati
AC repair in Cotati typically costs between $150 and $650, and most calls are completed same day when you reach us before early afternoon. We’re the AC Repair team that knows this pocket of Sonoma County inside out, from the older tracts off East Cotati Avenue to the rental conversions near the Rohnert Park line. Our dispatch runs from the San Francisco Bay Area office, but our crews live and work locally, which means we’re not driving down from Santa Rosa or up from Novato when your compressor quits on a 90-degree afternoon. Call (984) 538-9003 and a live person answers, 24 hours a day. You’ll get a name, a photo, and a written price before anyone touches your system.
Why Brandt HVAC Is Cotati’s Preferred AC Repair Company
We’ve been handling AC Repair in Cotati long enough to know the real problem isn’t always the part that failed. It’s the 1970s ductwork that was never meant to carry cold air, or the attic that bakes at 140°F because insulation standards were different when these homes went up. Our technicians are background-checked, identity-verified, and introduced by name and photo before every visit through our Threshold Verified standard. If someone shows up at your door who you weren’t expecting, that visit is on us, period.
Our phones are answered by a live person, never an automated tree, never a callback queue. Nights, weekends, holidays, it doesn’t matter. We send a written price before any work starts, every single time, and every repair carries our 365-Day Done Right Promise. If it fails, we return at no charge. No argument, no additional fee. Cotati homeowners tell us this matters more than a cheap quote that balloons once the truck arrives.
AC Unit Repair in Cotati
AC Unit Repair in Cotati means diagnosing why your system isn’t cooling and fixing it in one trip when possible, with a written price you approve before we start. Most Cotati homes with central air were retrofitted onto old heating-only duct systems, so our diagnosis always includes checking whether the problem is the unit itself or the delivery path. A typical AC Unit Repair in Cotati runs $150 – $650, depending on whether we’re replacing a contactor or addressing a compressor issue.
When the Compressor Won’t Start
The compressor is the heart of your outdoor unit, and in Cotati’s marine-influenced climate, corrosion from salt-laden fog can eat at electrical connections faster than in inland Sonoma County. We test amp draw, check start components, and verify your refrigerant charge before condemning a compressor. Many times what looks like compressor failure is actually a $200 capacitor or contactor fix.
Refrigerant Leaks in Older Systems
Systems installed during the first wave of AC retrofits in Cotati are often 15 – 20 years old now, running R-22 refrigerant that’s no longer manufactured. We leak-test with electronic detectors and nitrogen pressure tests, then give you honest numbers: repair the leak and recharge, or put that money toward a modern system. You’ll get both options in writing.
AC Capacitor Replacement in Cotati
AC Capacitor Replacement in Cotati is one of the most common calls we get during heat spikes, especially when the Petaluma Gap stalls and temperatures jump from the 70s to the 90s overnight. Capacitors store the electrical charge that starts your compressor and fan motor, and they fail under stress, age, or voltage fluctuation. In Cotati, where many systems are working harder than their original design intended, capacitor failure is routine. A typical AC Capacitor Replacement in Cotati runs $150 – $340, parts and labor included.
Dual Run vs. Single Capacitors
Most residential systems use a dual-run capacitor that serves both the compressor and the outdoor fan. When it weakens, you might hear a humming outdoor unit with no fan spin, or the compressor tries to start and trips the breaker. We stock the common sizes for Goodman, Rheem, and York systems, which covers most of what we see in Cotati’s housing stock.
Why Capacitors Fail Faster Here
Cotati’s wind-blown dust and occasional fog corrosion stress electrical components more than people expect. Systems that cycle on and off frequently, short-cycling because of undersized ductwork, put extra load on capacitors. We always check for underlying causes so you’re not replacing the same part twice.
Trusted Brands We Service in Cotati
We service all major residential HVAC brands, including Carrier, Trane, Lennox, Goodman, Rheem, York, Daikin, Bryant, and American Standard. For Cotati homeowners, this means we stock common parts locally and don’t need to special-order capacitors, contactors, or fan motors for most same-day repairs. Goodman and Rheem systems are particularly common in the 1970s and 1980s tract homes around Cotati’s core, and our trucks carry the contactors, capacitors, and refrigerant fittings those units typically need. York and Daikin equipment shows up more often in recent retrofits and ductless additions. Whatever brand is keeping your home comfortable, we have the technical literature and factory training to repair it right.
Common AC Repair Problems We See in Cotati Homes
- Undersized ductwork from heating-only retrofits. The modest ranch homes off West Sierra Avenue and throughout the 94931 zip code often have trunk lines sized for furnace airflow. When AC is added, the same ducts can’t move enough volume, causing weak vents, frozen coils, and compressor strain.
- Attic heat overwhelming air handlers. Minimal insulation in 1960s – 70s attics means air handlers and ductwork bake at temperatures that reduce cooling output before the air ever reaches your living room. We measure temperature drop and check duct leakage on every call.
- Refrigerant leaks at flare fittings from retrofits. Installer skill varies widely on retrofit jobs, and we’ve found poorly torqued flare connections leaking slowly for years. Our electronic leak detectors find what soap bubbles miss.
- Thermostat location causing short cycling. Older Cotati homes often have thermostats on walls that get afternoon sun or near the kitchen, reading 5 – 10 degrees high and shutting off the system before the bedrooms ever cool.
Pricing for AC Repair in Cotati, CA
Most AC repairs in Cotati fall between $150 and $650, with the majority of calls landing in the $200 – $400 range. Here’s how typical repairs break down:
| Repair Type | Typical Range in Cotati |
|---|---|
| Capacitor or contactor replacement | $150 – $340 |
| Refrigerant recharge (with leak repair) | $300 – $650 |
| Fan motor replacement | $350 – $650 |
| Compressor repair or replacement | $500 – $650+ (may exceed range) |
| Thermostat replacement | $180 – $400 |
What moves you up or down within these ranges? The part itself, whether your system uses R-22 or modern R-410A refrigerant, and accessibility. A capacitor on a ground-level condenser is quick; a fan motor in a tight attic crawlspace takes longer. We give you a written, itemized price before any work starts. No exceptions. Estimates are free, and there’s no charge for the diagnostic if you choose to proceed with the repair. Call (984) 538-9003 for your exact quote.
We Also Serve Cities Near Cotati
Our crews work throughout central Sonoma County, including Furnace Repair in Cotati and neighboring communities. We regularly dispatch to Rohnert Park, Petaluma, Santa Rosa, and Sebastopol. If you’re in the Cotati area or anywhere along the 101 corridor between Petaluma and Santa Rosa, we’re your local team. We also handle AC Maintenance in Cotati to help prevent the repairs we’re discussing here.
Serving Cotati, CA - Our Local Coverage Area
We’re based in the Cotati area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About AC Repair in Cotati
Same-day service is available for most Cotati calls received before 2 PM, and emergency calls are prioritized when the Petaluma Gap stalls and temperatures spike rapidly. Our dispatch coordinates from the San Francisco Bay Area office, with local crews already in the field around Sonoma County. Call (984) 538-9003 for a live person who can give you today’s availability.
Yes, we service the full Cotati area, from the older tracts near La Plaza Park to the rental conversions along the Rohnert Park border and everything along East and West Cotati Avenue. Every neighborhood gets the same Threshold Verified standard: named, photographed technician, written price upfront, and 365-Day Done Right Promise.
Yes, a live person answers our phones 24 hours a day, 7 days a week, including nights, weekends, and holidays. We don’t use voicemail or callback queues. After-hours emergency rates apply for true middle-of-the-night calls, but you’ll know the exact price before we dispatch.
Cotati’s retrofit-heavy housing stock often means more diagnostic time figuring out whether the problem is the unit, the ductwork, or both. That complexity can push some repairs toward the higher end of our $150 – $650 range. However, our pricing structure is consistent across Sonoma County; you’re not paying a Cotati premium, just getting honest diagnosis of systems that are more challenging than purpose-built AC installations.
Every repair includes our 365-Day Done Right Promise in writing. If the same part or the same problem recurs within 365 days, we return and make it right at no charge. No argument, no additional diagnostic fee, no questions about whether it was something else. Parts carry manufacturer warranties where applicable, and we handle that paperwork for you. Call (984) 538-9003 for your free estimate.
Written by Devin Marlowe, Owner at Brandt HVAC, serving Cotati and Sonoma County with Threshold Verified technicians and upfront pricing on every job.







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