Understanding SEER2 and EER for Through-the-Wall Heat Pump Units

📊 Why SEER2 and EER Matter More Than Ever

When buying a through-the-wall air conditioner or heat pump, you’ll see ratings like SEER2 and EER all over the product specs. These aren’t just technical jargon — they directly impact:

• Your comfort

• Your electric bills

• Federal tax credit eligibility

• Long-term system efficiency

As Mike Sanders always says:

"You wouldn’t buy a car without checking the MPG — don’t buy an AC without checking SEER2 and EER."

🔢 SEER2 vs. EER: Quick Definitions

Metric	Full Name	What It Measures
SEER2	Seasonal Energy Efficiency Ratio (Version 2)	Total cooling efficiency over an entire season
EER	Energy Efficiency Ratio	Cooling efficiency at a fixed temperature (peak conditions)

Reference: Energy Star Definitions

🔄 What Changed from SEER to SEER2?

In 2023, the U.S. Department of Energy updated test procedures:

• SEER (old): Based on lighter test conditions not reflecting real-world loads.

• SEER2 (new): Accounts for realistic external static pressure, closer to how systems perform installed in homes.

Key Difference:

• SEER2 ratings are lower numerically than SEER for the same system due to tougher testing.

Reference: Department of Energy SEER2 Rule

📏 Typical SEER2 and EER Values for Through-the-Wall Units

Product Type	Typical SEER2	Typical EER
Window AC	9.4 – 10.5 SEER2	8.5 – 10.0 EER
Through-the-Wall Straight Cooling	10.0 – 12.5 SEER2	9.0 – 11.0 EER
Through-the-Wall Heat Pump (Amana PBH092J12AA)	12.2 SEER2	9.2 EER

Reference: Amana PBH092J12AA Specs

⚡ Why SEER2 Matters More for Heat Pumps

• Heat pump models run year-round, maximizing SEER2 benefits.

• High SEER2 means lower operating costs during long cooling seasons.

• Modern heat pumps like the Amana PBH092J12AA deliver excellent SEER2 without sacrificing heating capacity.

For example:

• A 9,000 BTU unit operating 1,000 hours/year at 12.2 SEER2 uses ~736 kWh annually.

• A less efficient 9.5 SEER2 model would use ~947 kWh/year — nearly 29% more electricity!

Reference: Energy.gov Efficiency Calculations

🔎 How EER Complements SEER2

• EER reflects efficiency at maximum cooling load (typically 95°F outdoor temp).

• Higher EER = better peak performance during extreme heat waves.

Why This Matters:

• SEER2 averages performance; EER shows hot weather resilience.

• A unit with high SEER2 but low EER may struggle during severe heat.

Reference: HVAC.com EER vs SEER Explained

💸 Tax Credits and Rebates: SEER2 Thresholds Matter

Thanks to updated federal incentives, high-efficiency through-the-wall heat pumps may qualify for:

• 25C Federal Tax Credit (Inflation Reduction Act 2022)

• Rebates from state and local utility companies

• Utility demand-side management programs

2025 Federal Requirements (for maximum credit):

• Through-the-wall heat pumps typically need:

  • SEER2 ≥ 16 (for maximum 25C tax credit)

  • EER ≥ 12.0

Note: Most through-the-wall models like the Amana PBH092J12AA do not meet the highest federal rebate thresholds but may still qualify for partial credits or local incentives.

Reference: IRS Energy Efficient Home Improvement Credit

🏷 The Cost Efficiency Balance

Feature	Low SEER2 Unit	High SEER2 Unit (Heat Pump)
Unit Cost	Lower	Higher
Monthly Energy Bills	Higher	Lower
Total ROI	Lower over 5-10 years	Significantly higher

Mike’s Rule of Thumb:

"In regions with long cooling seasons, investing in higher SEER2 pays off fast. If you’re only cooling 2 months per year, basic efficiency is fine."

🌎 Climate Zone Impact on Efficiency Payback

Climate Zone	SEER2 Impact
Southeast US	Huge energy savings year-round
Southwest US	Major cost benefit due to extreme heat
Midwest/Northeast	Moderate savings
Pacific Northwest	Minor savings unless using year-round heat pump

Reference: ASHRAE Climate Zones

🔧 Other Factors That Influence Efficiency

• Wall sleeve fitment (air leaks reduce efficiency)

• Proper drainage management

• Regular filter cleaning

• Outdoor obstructions blocking airflow

• Correct sizing based on room square footage

Reference: The Spruce: Through-the-Wall AC Installation Guide

🏆 Mike Sanders' Bottom Line

"For through-the-wall heat pump shoppers, SEER2 is the new king. Look for at least 12 SEER2 minimum as your starting point. If you live where summers are long and brutal, every extra SEER2 point is worth hundreds in lifetime savings."