Not all cooling systems are created equal. The size and design of an air conditioner or heat pump can have a major impact on how well it performs and how efficiently it runs.

SEER stands for seasonal energy efficiency ratio — an industry-standard metric that measures how efficiently an air conditioner cools a space over a typical cooling season. But just because an AC has a higher SEER rating than a competitor doesn’t automatically make it the best fit for your home.

If you’re thinking about upgrading your AC, heat pump, or ductless mini-split, understanding SEER ratings can give you a clearer picture of cooling performance. In this guide, we’ll break down how SEER works and why it matters when choosing a new air conditioner.

Understanding the SEER Rating System

Seasonal energy efficiency ratio is a simple way to measure how efficiently your air conditioner or heat pump cools your home over an entire season compared to how much energy it uses.

Here’s how it works: The higher the SEER rating, the more energy-efficient the unit. It’s calculated by dividing a cooling system’s total seasonal output by the energy it consumes. Every home is different, and factors like square footage, insulation, and daily usage all play a role in determining which system is best for your home.

What’s a Good SEER Rating?

Older cooling systems typically range between 8 to and SEER, making them inefficient by today’s energy and environmental standards.

Modern air conditioners and heat pumps fall between 14 and 26 SEER, although mini-splits could achieve even higher efficiency.

• Standard units must have a 14 to 17 SEER2 rating.
• Mid-range units must have an 18 to 20 SEER2 rating.
• High-efficiency units must have a 21 SEER2 rating or higher.

SEER Regulations

As of 2023, the U.S. Department of Energy (DOE) updated its minimum efficiency standards:

• In Northern states, new residential AC systems must be at least 14 SEER or 13.4 SEER2.
• In Southern states like Maryland, where AC use is heavier, the minimum is now 15 SEER or 14.3 SEER2.

SEER Rating vs. Actual Efficiency

While SEER gives a good sense of a system’s potential efficiency, it’s based on ideal lab conditions — not real-world use. That’s where SEER2 comes in.

SEER2 is a newer HVAC metric that factors in real-life conditions like ductwork layout, airflow restrictions, and typical system installation, making it a more accurate reflection of a cooling system’s performance.

Other HVAC Efficiency Metrics

Still, efficiency depends on more than just a rating. Local climate, daily usage, and routine maintenance all play a big part in how well your system runs.

For a complete picture of HVAC efficiency, it’s also helpful to consider other ratings:

• EER (energy efficiency ratio) is often used in very hot climates or for window units.
• HSPF (heating seasonal performance factor) is used to measure heating efficiency for heat pumps.

Benefits of a Higher SEER Rating

A high-SEER system offers more than just comfort — it’s an investment in savings, energy efficiency, and sustainability. By installing a system rated 15 SEER or higher, you’ll enjoy:

• Lower energy bills
• A reduced carbon footprint
• Eco-friendly, efficient cooling
• Future-proof HVAC
• Potential HVAC rebates and tax incentives

How To Choose the Right SEER Rating for Your Home

Choosing the right SEER rating isn’t one-size-fits-all. Here are a few considerations to help you make the smartest choice:

• Consider your environment: Baltimore’s humid climate means a higher SEER rating is better.
• Think about long-term savings: While a new AC comes with upfront costs, a higher-efficiency system can lower monthly utility bills over time.
• Consult an expert: A licensed HVAC professional can help you properly size, assess, and install the right air conditioner for your home.

Why Choose United Air Temp for AC Installation?

If you’re ready to upgrade or replace your air conditioner, our highly trained technicians are here to help. United Air Temp delivers exceptional cooling, heating, and indoor air quality solutions to Baltimore homeowners, prioritizing comfort and customer experience.

We offer same-day service, so you can get the support you need — fast. Our team always goes the extra mile for our customers, backed by a long-standing commitment to craftsmanship and community.

High-quality services and products since 1931. Call today to request a free estimate for a new AC in Baltimore, MD.