AHRI Standards Ratings
Overview
The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) establishes performance and rating standards for HVAC and refrigeration equipment. AHRI standards define test conditions, measurement procedures, and rating methodologies that ensure consistent equipment evaluation across manufacturers.
AHRI Certification Programs
AHRI operates voluntary certification programs that verify manufacturer claims through independent testing.
Certification Process
- Manufacturer Participation: Manufacturers submit equipment for certification
- Sample Selection: Random samples selected from production units
- Third-Party Testing: Independent laboratories conduct tests per AHRI standards
- Data Verification: Test results compared against published ratings
- Directory Publication: Certified equipment listed in AHRI directories
- Ongoing Surveillance: Periodic retesting maintains certification validity
Certified Product Directories
AHRI publishes directories of certified equipment accessible online. Each listing includes:
- Model numbers and variations
- Capacity ratings at specified conditions
- Efficiency metrics (SEER, EER, IPLV, COP)
- Operating voltage and phase
- Refrigerant type and charge
- Sound ratings
- Certification date and status
Equipment Rating Standards
AHRI 210/240 Unitary Air-Conditioners and Heat Pumps
Covers residential and light commercial equipment up to 65,000 Btu/h cooling capacity.
Key Rating Metrics:
| Metric | Test Condition | Application |
|---|---|---|
| SEER (Seasonal Energy Efficiency Ratio) | Weighted seasonal average | Primary efficiency metric for cooling |
| EER (Energy Efficiency Ratio) | 95°F outdoor dry bulb | Peak load performance |
| HSPF (Heating Seasonal Performance Factor) | Seasonal heating average | Heat pump heating efficiency |
| COP (Coefficient of Performance) | 47°F outdoor for heating | Instantaneous heating efficiency |
SEER Calculation: Based on total seasonal cooling output divided by total electrical energy input during a typical cooling season. Test conditions range from 65°F to 104°F outdoor temperature.
Current Minimum Standards:
- Split systems: SEER 14.0 (southern regions), SEER 13.0 (northern regions)
- Package units: SEER 14.0
- Heat pumps: SEER 14.0, HSPF 8.2
AHRI 310/380 Packaged Terminal Equipment
Applies to through-the-wall air conditioners and heat pumps (PTACs and PTHPs).
Rating Conditions:
- Cooling: 95°F outdoor dry bulb, 80°F/67°F indoor dry bulb/wet bulb
- Heating: 47°F outdoor, 70°F indoor
- Standard wall sleeve installation
Performance Requirements:
- EER varies by capacity: EER = 12.0 - (0.3 × capacity in 1000 Btu/h)
- Minimum COP for heat pumps: 3.0 at 47°F outdoor
AHRI 340/360 Commercial and Industrial Unitary Equipment
Covers commercial unitary air conditioners and heat pumps exceeding 65,000 Btu/h.
Rating Points:
| Equipment Type | Cooling Capacity | Primary Metric |
|---|---|---|
| Air-cooled <135,000 Btu/h | 65,000-135,000 Btu/h | EER and IEER |
| Air-cooled ≥135,000 Btu/h | ≥135,000 Btu/h | EER and IEER |
| Water-cooled | All capacities | EER and IPLV |
IEER (Integrated Energy Efficiency Ratio): Part-load efficiency metric calculated from performance at four operating points:
- 100% capacity at 95°F outdoor
- 75% capacity at 81°F outdoor
- 50% capacity at 68°F outdoor
- 25% capacity at 65°F outdoor
IEER Formula: IEER = 0.020A + 0.617B + 0.238C + 0.125D
Where A, B, C, D are EER values at 100%, 75%, 50%, and 25% load respectively.
AHRI 365 Commercial and Industrial Air-Source Heat Pumps
Establishes ratings for large commercial heat pumps.
Test Conditions:
- Cooling: 95°F outdoor, 80°F/67°F indoor
- Heating standard: 47°F outdoor, 70°F indoor
- Heating low temperature: 17°F outdoor, 70°F indoor
Performance Metrics:
- EER for cooling at full load
- COP for heating at 47°F and 17°F
- IPLV for part-load cooling efficiency
AHRI 400 Liquid-to-Liquid Heat Exchangers
Covers shell-and-tube, brazed plate, and other liquid heat exchangers.
Rating Requirements:
- Fouling factors specified for both fluid sides
- Pressure drop at rated flow
- Heat transfer capacity at specified inlet temperatures and flow rates
- Materials of construction
Standard Test Conditions: Varies by application (water-to-water, glycol solutions, refrigerant-to-water).
AHRI 410 Forced-Circulation Air-Cooling and Air-Heating Coils
Defines rating for chilled water and hot water coils.
Coil Performance Data:
| Parameter | Cooling Coils | Heating Coils |
|---|---|---|
| Capacity | Sensible and total | Total heat output |
| Air pressure drop | At rated CFM | At rated CFM |
| Water pressure drop | At rated GPM | At rated GPM |
| Entering air conditions | 80°F DB/67°F WB | 70°F DB |
| Water temperature | 45°F entering | 180°F entering |
Fouling Factors: 0.0005 hr·ft²·°F/Btu for water side.
AHRI 430 Central Station Air-Handling Units
Establishes performance and construction standards for custom and semi-custom air handlers.
Certification Criteria:
- Casing thermal performance (R-value and thermal bridging)
- Air leakage at specified pressures
- Casing deflection under pressure
- Structural integrity
- Access and serviceability
Air Leakage Classes:
| Class | Maximum Leakage (CFM/ft² at 4" w.g.) |
|---|---|
| 1 | 12 |
| 2 | 8 |
| 3 | 4 |
| 6 | 2 |
| 12 | 1 |
AHRI 440 Room Fan-Coils
Covers ratings for room-level terminal units.
Rating Conditions:
- Cooling: 80°F/67°F entering air, 45°F entering water
- Heating: 70°F entering air, 200°F entering water
- Three fan speeds: high, medium, low
Published Data:
- Capacity at each fan speed
- Water flow rate
- Air flow rate (CFM)
- Sound power levels
AHRI 550/590 Water-Chilling and Heat Pump Water-Heating Packages
Comprehensive standard for chillers using mechanical compression cycle.
Primary Rating Conditions:
| Chiller Type | Evaporator | Condenser | Application |
|---|---|---|---|
| Air-cooled | 44°F leaving water | 95°F entering air | Standard rating |
| Water-cooled | 44°F leaving water | 85°F entering water | Standard rating |
| Evaporatively-cooled | 44°F leaving water | 75°F entering WB | Standard rating |
IPLV (Integrated Part Load Value): Critical metric for annual energy consumption estimation.
IPLV Calculation: IPLV = 0.010A + 0.42B + 0.45C + 0.12D
Where:
- A = EER at 100% load, standard conditions
- B = EER at 75% load, reduced condenser temperature
- C = EER at 50% load, reduced condenser temperature
- D = EER at 25% load, reduced condenser temperature
Part-Load Test Conditions:
| Load | Air-Cooled Condenser Temp | Water-Cooled Condenser Temp |
|---|---|---|
| 100% | 95°F DB | 85°F entering |
| 75% | 75°F DB | 75°F entering |
| 50% | 65°F DB | 65°F entering |
| 25% | 55°F DB | 55°F entering |
Non-Standard Rating Points: AHRI 550/590 also defines rating at:
- Low ambient cooling conditions
- High ambient conditions (115°F for air-cooled)
- Ice storage charging conditions
AHRI 560 Absorption Water Chilling and Water Heating Equipment
Establishes performance criteria for absorption chillers.
Rating Conditions:
- Single-effect: 44°F chilled water, 95°F cooling water, hot water or steam heat source
- Double-effect: Same water temperatures, higher temperature heat source
- COP based on heating energy input plus parasitic power
Heat Source Specifications:
- Low-pressure steam: 12-15 psig
- Hot water: 230-270°F
- Direct-fired: natural gas or fuel oil
AHRI 700 Refrigerant Specifications
Defines purity requirements and testing methods for refrigerants.
Specifications Include:
- Chemical composition limits
- Moisture content (typically <10 ppm)
- Non-condensable gas content
- High boiling residue
- Acidity
- Particulate matter
Common Refrigerants Covered:
- R-410A (HFC blend for residential equipment)
- R-134a (HFC for chillers)
- R-32 (Lower GWP alternative)
- R-1234yf and R-1234ze (HFO low-GWP refrigerants)
- R-717 (ammonia for industrial applications)
- R-744 (CO₂ for transcritical systems)
AHRI 740 Performance of Refrigerant Recovery, Recycling, and Reclaim Equipment
Establishes requirements for refrigerant handling equipment.
Recovery Equipment Requirements:
- Recovery rate (lbs/min) at specified conditions
- Final vacuum level achievable (typically 0" Hg for vapor recovery, 4" Hg for liquid recovery on small equipment)
- Purity of recovered refrigerant
- Non-condensable gas separation
Recycling Equipment Standards:
- Moisture reduction to <50 ppm
- Acid removal
- Particulate filtration to 10 microns
- Oil separation efficiency
Application of AHRI Ratings
Equipment Selection
When selecting equipment, AHRI ratings provide standardized comparison:
- Verify Certification: Check equipment appears in AHRI directory
- Compare at Same Conditions: Ratings at standard conditions enable direct comparison
- Consider Part-Load Performance: IPLV or IEER often more important than full-load EER for annual energy use
- Account for Operating Conditions: Adjust for site-specific conditions when actual operating temperatures differ from rating conditions
Energy Code Compliance
ASHRAE 90.1 and IECC reference AHRI minimum efficiency requirements:
- Equipment must meet or exceed minimum EER, SEER, IPLV values
- Testing and rating per AHRI standards demonstrates compliance
- Submittals include AHRI directory listing page or certification letter
Performance Verification
AHRI certification provides assurance:
- Independent third-party testing validates manufacturer claims
- Ratings accuracy within specified tolerances (typically ±5% for capacity, efficiency)
- Challenge testing process addresses non-compliant equipment
Limitations and Considerations
Rating Conditions vs. Actual Operation:
- AHRI standard conditions may not match site-specific installations
- Actual performance varies with:
- Outdoor ambient temperature
- Indoor load conditions
- Duct or piping system effects
- Refrigerant line lengths (split systems)
- Altitude corrections
Installation Effects:
- Field installation quality impacts actual performance
- Improper refrigerant charge reduces efficiency
- Airflow restrictions lower capacity and efficiency
- Non-standard configurations void ratings
Application Range:
- Ratings apply to specific capacity ranges and equipment types
- Operating outside rated range affects performance
- Multiple rating standards may apply to single equipment category