You’re staring at three HVAC quotes. One says SEER 16, another SEER2 14.3, and the third mentions HSPF, EER, and COPF. If you’re confused, you’re not alone.
The world of HVAC efficiency ratings can feel like alphabet soup. But each of these numbers has a specific purpose—and understanding them can help you make a smarter decision about which system is right for your home.
In this article, we’ll explain what all these terms mean in plain English and give you a framework for what actually matters when comparing efficiency.
SEER: Seasonal Energy Efficiency Ratio
SEER tells you how efficiently an air conditioner or heat pump cools your home during an average cooling season.
- Higher SEER = better cooling efficiency
- Calculated over a full season, not just a snapshot
- Older systems may have SEER ratings of 10–13, while modern systems are typically 14–20+
Think of SEER like miles per gallon (MPG) for your AC. The higher the number, the less electricity it needs to keep you cool.
SEER2: The Updated Testing Standard
SEER2 is the new version of SEER, rolled out in 2023 to better reflect real-world conditions. The testing method is tougher and more accurate.
- A SEER2 rating of 14.3 is roughly equal to the old SEER 16
- You may see both numbers on new equipment specs
Why it matters: It helps you compare apples to apples with current regulations and energy codes.
HSPF: Heating Seasonal Performance Factor
HSPF applies to heat pumps and measures heating efficiency during an average heating season.
- Higher HSPF = more efficient heating
- Older heat pumps may be rated around 7–8; newer ones are often 9–11+
If you use a heat pump for winter heating, this number directly impacts your comfort and electric bill.
EER: Energy Efficiency Ratio
EER is similar to SEER but measures cooling performance at a single, steady-state condition (usually 95°F outdoor temperature).
- Useful for evaluating performance in consistently hot climates
- Good supplement to SEER but not as comprehensive for seasonal use
Think of EER as the AC’s performance on its hardest day.
COP / COPF: Coefficient of Performance
COP (or COPF) is another heating efficiency metric, often used in electric heat pumps.
- It’s a ratio of heat output to energy input
- A COP of 3.5 means the system provides 3.5 units of heat for every unit of electricity consumed
This number isn’t always listed on residential quotes but can appear in technical specs.
What’s a “Good” Efficiency Rating?
Efficiency is just one piece of the puzzle. Here’s a simplified guide:
- SEER2: Look for 14.3 or higher (the current baseline)
- HSPF: 9+ is solid for heating comfort
- COP: Anything above 3 is generally efficient
But be cautious—higher doesn’t always mean better in real life. Here’s why:
- A high-efficiency system installed on poor ductwork won’t perform well
- Improper sizing can waste energy and shorten lifespan
- More efficient systems may need more maintenance and upfront cost
How Northwest HVAC Helps You Decide
We don’t just recommend the highest SEER system on the market. We design the right system for your home based on:
- How much you use heating vs. cooling
- What type of ductwork you have
- Local climate and home orientation
- Your budget, comfort goals, and efficiency priorities
Our comfort consultants (who are former technicians) will explain every number and how it translates into real-world performance for your home.
Because the truth is, you shouldn’t need a degree in physics to feel confident about your HVAC investment.
We make it simple, so you can make a smart decision—and feel good about it for years to come.
About Northwest HVAC Service
Northwest HVAC Service is a family-owned business proudly serving Vancouver, WA and surrounding communities since 1998. We specialize in residential retrofit HVAC systems, including ductless upgrades, electric heat pumps, airflow redesign, and comfort diagnostics. Whether you’re replacing outdated equipment or trying to fix long-standing comfort issues, we bring honest advice, expert service, and long-term solutions you can trust.