Southern California living means mild winters, hot spells, marine air, and wildfire smoke season. Your heating and cooling system works year-round to keep temperatures steady and air clean. A practical HVAC maintenance checklist helps you save energy, avoid breakdowns, and protect indoor air quality. It also reduces safety risks and preserves warranties—many insurers and home warranties expect proof of maintenance by a qualified professional when claims arise.

Why this checklist matters

Well-maintained HVAC equipment runs quieter, lasts longer, and uses less energy. In our region, salt-laden coastal air, valley heat, and dust from dry months are hard on outdoor condensers, blower motors, and filters. Routine care keeps airflow strong and humidity balanced. Most importantly, proper maintenance helps prevent hazards such as carbon monoxide leaks, electrical shorts, or water damage from clogged condensate lines.

Safety first: what not to DIY

• Refrigerant work: charging, recovering, or opening the sealed circuit requires specialized tools and certifications. Improper handling can cause injury and void warranties.
• Gas furnaces and heat exchangers: combustion, venting, and pressure settings must be tested with calibrated instruments; mistakes can lead to CO exposure.
• High-voltage diagnostics: capacitor, contactor, ECM/variable-speed electronics, and control boards carry shock risks and demand manufacturer procedures.
• Structural or code-critical tasks: new circuits, flue changes, roof penetrations, or duct reroutes typically require permits and inspection. Insurers often require licensed work and documentation.

Monthly and seasonal homeowner tasks

• Replace or clean filters: check monthly during heavy use. Aim for the right MERV rating—often MERV 8–11 for most homes; higher MERV can improve capture of smoke and fine dust but may require duct and blower verification for airflow.
• Thermostat check: confirm schedules, batteries, and temperature accuracy. Use setbacks and smart features to trim bills without sacrificing comfort.
• Clear supply and return vents: keep furniture and drapes away. Vacuum grilles to reduce dust and improve airflow.
• Outdoor unit clearance: maintain at least 24 inches around the condenser/heat pump. Trim bushes, remove leaves, and gently rinse coil fins from the outside in.
• Condensate drain: ensure steady drip when cooling. If you see standing water, musty odors, or float-switch shutdowns, stop and schedule a professional cleaning.
• Listen and look: new rattles, grinding, ice on refrigerant lines, or short cycling are early warning signs; take notes for a technician.
• Safety devices: test smoke and carbon monoxide alarms monthly and replace batteries on schedule.

Professional annual and biannual tasks

• Airflow and static pressure testing: verifies duct sizing, cleanliness, and register balance to protect motors and ensure comfort room-to-room.
• Duct leakage assessment and sealing: reduces energy loss, dust infiltration, and uneven temperatures.
• Refrigerant diagnostics: superheat/subcooling checks confirm charge, metering device performance, and coil health.
• Electrical inspection: capacitors, contactors, wiring, and ECM tuning—critical for efficiency and reliability.
• Combustion analysis (heating): verifies proper fuel-to-air ratio, flue draft, and heat exchanger integrity.
• Drain system service: safe cleaning of condensate pans, traps, and lines; verification of overflow protection.
• Manufacturer-specific updates: firmware or control strategies often require factory procedures to preserve warranties and documentation insurers recognize.

Indoor air quality essentials

• Filtration strategy: pair the right MERV with blower capability. Consider a high-performance media filter or dedicated air cleaner for wildfire season.
• Humidity balance: 40–60% RH is a comfort and health sweet spot. Oversized or poorly controlled systems can swing humidity; variable-speed equipment helps.
• Ventilation: balanced fresh air and exhaust reduce CO2 and VOCs. Verify bath and kitchen fans actually move rated airflow.
• Duct hygiene: sealing, insulation, and proper returns reduce dust and hot/cold spots; unnecessary “duct cleanings” are not a substitute for leak repair.

Upgrades that pay off in our climate

Variable-speed heat pumps, ductless mini-splits, and high-efficiency air handlers can improve comfort and cut energy use when correctly designed and commissioned. Our fourth-generation family of engineers at #1 AC Guys brings 80+ years of engineering know-how to complex residential and commercial projects. Our team has been trained at manufacturer facilities of Fujitsu (Japan), Mitsubishi Elektrik (Thailand), Midea (China), Gree (China), and Hier (China), which supports precise setup of advanced systems. Proper load calculations, duct design, and control programming are essential for SEER2/HSPF2 performance to show up on your utility bill.

Regional considerations for Southern California

• Coastal corrosion: in beach cities, rinse condenser coils more often and consider protective coatings.
• Wildfire smoke: upgrade filtration during events and switch to recirculation to limit outdoor intake when advised by authorities.
• Heat waves: verify attic insulation, duct sealing, and shading; these reduce runtime and protect equipment.
• Commercial and multi-family: commissioning, ventilation balance, and controls verification are crucial for comfort and code alignment.

Documentation, codes, and insurance

Keep a simple HVAC log: filter changes, dates of professional service, and any findings. Many equipment warranties and some insurance policies expect maintenance records and licensed work for covered failures. That documentation can make the difference during a claim after water damage, electrical issues, or a condensation overflow.

Service area

We serve Los Angeles County and nearby areas, including Orange County, Ventura County, and Western Riverside County. Common cities include Los Angeles, Long Beach, Pasadena, Glendale, Burbank, Santa Clarita, West Hollywood, Anaheim, Irvine, Santa Ana, Fullerton, Huntington Beach, Ventura, Oxnard, Thousand Oaks, Riverside, Corona, Temecula, and Murrieta.

Who we are

#1 AC Guys is a family-owned HVAC company in Southern California. We are fourth-generation engineers with 80+ years of engineering experience, focused on healthy air for a healthy life. We specialize in residential and commercial work, especially large and complex projects that demand careful engineering. Our engineers have trained at the factories of Fujitsu (Japan), Mitsubishi Elektrik (Thailand), Midea (China), Gree (China), and Hier (China). While this guide empowers homeowners with routine steps, many HVAC tasks are not safe or practical to do alone—and insurers often require qualified specialists. Use this checklist to stay informed, protect your system, and know when professional expertise is essential.