What is SEER

SEER stands for Seasonal Energy Efficiency Ratio. It measures how efficiently an air conditioner or heat pump cools over an entire season, dividing total cooling output by the electricity it consumes. The higher the SEER, the less energy the system needs to deliver the same cooling. Think of SEER like miles per gallon for cooling: higher numbers mean better efficiency, especially during long, hot stretches.

You may also see EER, which focuses on efficiency at a single peak temperature, and HSPF (or HSPF2) for heating performance on heat pumps. All three help describe how a system will perform in real homes under different conditions.

SEER vs. SEER2 in 2023 and beyond

Since 2023, the U.S. has used updated testing standards called SEER2. SEER2 better reflects real-world conditions, including higher external static pressure in ducts. Roughly speaking, a 14.3 SEER2 unit is similar to a 15 SEER unit under the older scale. California follows these SEER2 standards, so when you compare options, be sure you are looking at the same rating type.

What SEER rating do I need in Southern California

Your ideal SEER depends on climate, home design, usage hours, electricity rates, and whether your ducts and building shell are in good shape. In Southern California, cooling needs vary from the coast to inland valleys:

• Coastal and near-coastal zones: 15–16 SEER2 is a strong value for moderate cooling seasons.
• Warm inland areas (San Fernando Valley, San Gabriel Valley, Santa Clarita, parts of Western Riverside County): 16–18 SEER2 can deliver meaningful utility savings during long run-times.
• High-use homes, larger houses, or multi-zone projects: 18–20 SEER2 (or higher with ductless) improves comfort and lowers bills when the system runs many hours each day.
• Ductless mini-splits for additions or room-by-room control: Many systems exceed 20 SEER2, offering very high efficiency and zoning flexibility.

Higher SEER brings diminishing returns. Moving from 14.3 to 16 SEER2 often pays back quickly in SoCal. Jumping from 18 to 20+ SEER2 may still be smart for heavy users, but the extra cost can take longer to recoup.

How SEER affects bills and comfort

• Energy savings: Efficiency is proportional. For example, compared to 14.3 SEER2, a 16 SEER2 system may use about 10% less electricity under similar conditions.
• Comfort upgrades: Many higher-SEER systems include variable-speed compressors and fans, which reduce temperature swings, improve humidity control, and cut noise.
• Utility rates: With tiered rates in Southern California, saving kilowatt-hours can matter more than the national average.

Other factors as important as SEER

• Right sizing (Manual J): Oversized systems short-cycle, waste energy, and miss humidity control. Undersized units run endlessly and wear out faster.
• Duct design and sealing: Leaky or undersized ducts erase SEER gains. Proper static pressure matters for SEER2 performance.
• Home envelope: Insulation, air sealing, and shade can cut cooling load so you may not need ultra-high SEER to hit comfort and cost targets.
• Thermostats and zoning: Smart controls and zoning improve comfort and reduce run-time.
• Filtration and IAQ: Correct filter MERV, clean coils, and balanced ventilation support both efficiency and healthier indoor air.

When higher SEER pays off

High-SEER systems shine when you cool many hours per day, have rising electricity costs, want lower noise and steadier temperatures, or plan to stay in your home long enough to enjoy the savings. Many models may qualify for utility rebates or federal incentives, and those programs can change—check current requirements and eligibility before you buy.

Safety, code, and insurance notes

Air conditioning involves high-pressure refrigerants and high-voltage circuits. Refrigerant handling typically requires EPA certification, and electrical work must meet code. DIY mistakes can lead to leaks, poor performance, or hazards. In many cases, warranty terms, local permits, and even insurance policies require installation and service by qualified, licensed professionals to keep coverage in force.

System types to consider

• Ducted central AC: Familiar, effective, and a good match when ducts are sized and sealed correctly.
• Heat pump (ducted or ductless): Delivers cooling and efficient electric heating; pairs well with modern controls and inverter technology.
• Ductless mini-split: High efficiency and zoning for additions, open concepts, or homes without ducts.
• Advanced multi-zone systems: For large or complex projects, variable-capacity multi-zone designs can deliver excellent comfort and control.

A quick decision guide

1. Estimate your cooling hours and peak needs (coastal vs. inland, occupancy patterns).
2. Evaluate ducts and envelope; fix leaks and insulation issues first.
3. Target a SEER2 range that fits your usage: 15–16 for moderate needs, 16–18 for warmer inland zones, higher for heavy use or zoning.
4. Choose right-sized, variable-capacity equipment where possible for comfort and savings.
5. Check rebates, permits, and code requirements before purchase.
6. Plan maintenance (clean filters, coil care, and annual checkups) to keep real-world efficiency high.

FAQs

Is SEER the same as SEER2? No. SEER2 uses updated test methods and is generally a bit lower for the same equipment, giving a more realistic picture of performance. A 14.3 SEER2 is roughly comparable to a 15 SEER (old scale).

Does SEER affect heating? SEER covers cooling. For heat pumps, heating efficiency is measured by HSPF or HSPF2; look at both SEER2 and HSPF2 if you need heating and cooling.

Is 20 SEER2 always worth it? Not always. It depends on run-hours, electricity rates, rebate incentives, and how long you’ll keep the home. Solid ducts and right-sizing can outperform an ultra-high-SEER unit installed poorly.

Will an oversized high-SEER unit save more? Usually no. Oversizing can waste energy and reduce comfort. Proper design beats brute force.

Who we are

#1 AC Guys is a family-owned HVAC company rooted in Los Angeles, Southern California. We are a fourth-generation family of engineers with 80+ years in engineering. Our engineers trained at manufacturer facilities for Fujitsu (Japan), Mitsubishi Elektrik (Thailand), Midea (China), Gree (China), and Hier (China). We handle commercial and residential projects, especially large and complex designs, with a mission focused on healthy air at home for a healthy life.

Service area: Los Angeles County and nearby regions including Orange County, Ventura County, and Western Riverside County. Examples include Los Angeles, Long Beach, Pasadena, Glendale, Burbank, Santa Monica, Anaheim, Irvine, Fullerton, Santa Ana, Huntington Beach, Ventura, Oxnard, Thousand Oaks, Camarillo, Riverside, Corona, Temecula, and surrounding communities.

Bottom line: Pick a SEER2 range that fits your climate, usage, and budget, and make sure the system is designed and installed to code. That combination delivers the real savings and comfort SEER promises.