Residential Emergency AC Service in Ontario, CA

Why Ontario homeowners trust #1 AC Guys for emergencies

We are a family-owned, 4th‑generation team with 80+ years of engineering experience, built to solve complex residential AC problems under pressure. Our engineers have trained at the factories of Fujitsu (Japan), Mitsubishi Electric (Thailand), Midea (China), Gree (China), and Haier (China), so we understand equipment deeply and fix issues at the source. From Ontario Ranch and Creekside to Historic Downtown Ontario and the airport district, we bring calm, clear communication and engineering-grade diagnostics to every home.

Our mission is simple: healthy air at home for a healthy life. That means fast restoration of cooling, careful protection of your indoor air quality, and solutions that meet California codes and best practices. We design repairs to last, optimize airflow, and leave your space clean so you can get back to comfort sooner.

Emergency AC issues we resolve fast

• No cooling or warm air blowing during heat waves
• Short cycling, breaker trips, or system won’t start
• Refrigerant leaks and low charge performance loss
• Frozen coils, clogged filters, and airflow restrictions
• Faulty capacitors, contactors, fan motors, and compressors
• Ductless mini-split errors and heat pump failures
• Thermostat and communication faults
• Indoor air quality concerns: odors, humidity, allergens

We service central AC, heat pumps, ductless mini-splits, and packaged rooftop units used in many Southern California homes. If you have a unique layout or a large, complex residence, our engineering background is tailor-made for it.

How our emergency visit works

• Rapid dispatch and arrival window updates so you are never guessing
• Safety-first inspection, then targeted diagnostics to find the root cause
• Clear, upfront repair options with good-better-best choices
• Same-day repairs whenever parts availability allows
• Performance verification: temperature split, airflow, and controls
• Clean-up and guidance to prevent repeat failures

Need after-hours help? We offer urgent, same-day and after-hours support to stabilize your home comfort, including temporary cooling options when full repairs must wait for parts. We prioritize seniors, families with infants, and heat-sensitive medical needs.

Healthy air first: comfort plus IAQ

Comfort is more than cool air. We help Ontario homeowners improve indoor air quality with right-sized filtration (MERV upgrades), sealed return air paths, coil cleaning, and balanced airflow. For homes that need more, we can recommend HEPA add-ons, UV-C coil treatment, humidity control, and fresh air strategies. We perform work with attention to California Title 24 requirements and manufacturer standards, and we handle refrigerants and materials in line with environmental guidelines.

If allergies, wildfire smoke, or humidity have been nagging problems, ask about targeted IAQ upgrades that pair perfectly with a repaired system to keep your family breathing easier.

What makes our team different

• 80+ years of engineering expertise, 4th‑generation family business
• Factory-trained at Fujitsu, Mitsubishi Electric, Midea, Gree, and Haier
• Precision diagnostics that prevent repeat breakdowns
• Clean, respectful workmanship and shoe-cover standards
• Transparent pricing with options, not pressure
• Expertise with complex homes and advanced controls

We specialize in both residential and commercial systems and excel at large or technically challenging projects. On residential emergency calls, that depth shows up as faster troubleshooting, smarter part selection, and smoother recoveries.

Serving Ontario and the greater LA area

Our residential emergency AC service covers Ontario, California (91761–91764) and nearby communities across the Greater Los Angeles region, including Los Angeles County and adjacent areas such as Orange County, Ventura County, and Western Riverside County. Whether you are near Ontario International Airport, Ontario Mills, Ontario Ranch, Creekside, or Historic Downtown, we are ready to help.

Be prepared before the next heat wave

Many emergencies can be avoided with seasonal maintenance. Ask about tune-ups that include coil cleaning, airflow checks, electrical testing, refrigerant evaluation, drain clearing, and thermostat calibration. A well-tuned system cools better, uses less energy, and is less likely to fail on the hottest day of the year.
And if your system is aging or undersized, we can engineer a right-sized replacement plan that improves comfort, reduces bills, and enhances air quality.

Call #1 AC Guys for residential emergency AC service in Ontario

When it is urgent, you need an experienced team that treats your home like their own. Contact #1 AC Guys for rapid residential emergency AC repair in Ontario, CA. We will restore comfort quickly, protect your indoor air, and back our work with the professionalism of a 4th‑generation family of engineers.