Use this checklist to verify that the installed system meets the new M1 testing standards and local regional requirements.
1. Equipment Matchup Verification
AHRI Certificate of Product Ratings: Does the outdoor unit, indoor coil, and furnace/air handler match a valid AHRI reference number? (Required for SEER2 validity).
Model Suffix Verification: Verify the "2" in the model number (e.g., XL15i vs XL15i2) to ensure it is an M1-rated chassis.
2. Airflow & Static Pressure
Total External Static Pressure (TESP) Test: Measured TESP is within manufacturer’s specifications (typically 0.5 in. wc. for SEER2 ratings). If > 0.7 in. wc., efficiency is compromised.
Blower Motor Configuration: Blower taps or dip switches adjusted to match the required CFM/ton specified in the AHRI directory for this specific matchup.
3. Refrigerant & Charge
TXV/Metering Device Match: Verify the TXV is SEER2 compliant and matched to the indoor coil capacity (essential for modulating/multi-stage systems).
Subcooling/Superheat Calculation: Charged based on liquid line length and manufacturer charging charts for the M1-rated unit.
4. Regional Documentation
EnergyGuide Label Retained: Ensure the SEER2 EnergyGuide label is provided to the homeowner for tax credit (25C) documentation.
South/Southwest Compliance: If in the South, verify installation date vs. SEER2 minimums (14.3 SEER2 for AC).
CRITICAL: Installing a non-matched system (e.g., a SEER2 condenser with a pre-2023 indoor coil) violates the manufacturer's warranty and likely fails DOE regional efficiency standards.