ANSI/ASHRAE Standard 140-2020 - Space-Cooling Equipment Performance Tests

Software Version: Better Building with EnergyPlus v25.1 | Date of Testing: 15/11/25 - 17/11/25 | Report Version: 1.0

1. Overview and Purpose

1.1 Introduction

This report documents the validation of Better Building energy modelling software against ANSI/ASHRAE Standard 140-2020, Section 9: Space-Cooling Equipment Performance Analytical Verification Tests. This validation provides independent verification of software accuracy in modelling unitary cooling equipment using manufacturer design data presented as empirically derived performance maps.

1.2 Validation Objectives

Software Capability Assessment: Evaluate Better Building's ability to model cooling coil performance, refrigerant-side and air-side heat transfer, part-load operation, and humidity control.

Quality Assurance: Establish confidence in cooling load calculations and equipment sizing for users, designers, consultants, and regulatory authorities.

Comparative Benchmarking: Ensure Better Building performs within accepted industry ranges for HVAC equipment modelling.

Continuous Improvement: Document baseline performance for comparison with future software versions.

1.3 Standard Overview

ANSI/ASHRAE Standard 140-2020 employs analytical verification and comparative testing methodology for HVAC equipment. Programs are evaluated by comparing results against analytical solutions, quasi-analytical solutions, and results from other validated simulation programs. The space-cooling equipment tests specifically evaluate the software's capability to model direct expansion (DX) cooling systems with empirically-derived performance maps across a range of operating conditions including sensible cooling, latent cooling, part-load ratios, and varying thermostat setpoints.

2. Scope of Testing

2.1 Tests Completed

Better Building has been tested against Section 9: Space-Cooling Equipment Performance Analytical Verification Tests of ANSI/ASHRAE Standard 140-2020, including:

• Base-case dry coil tests (Cases 100-140)

• High sensible heat ratio tests (Cases 150-165)

• Low sensible heat ratio tests (Cases 170-195)

• Full-load AHRI conditions test (Case 200)

2.2 Tests Explicitly Excluded

• Compressor/Condenser Fan Breakout: The EnergyPlus DX coil model does not provide separate output variables for compressor and condenser fan electricity consumption.

• Space Heating Tests: This validation focuses exclusively on cooling equipment performance per Section 9 of the standard.

2.3 Compliance Statement

Better Building has been tested according to ANSI/ASHRAE Standard 140-2020 for space-cooling equipment performance analysis. Results demonstrate that Better Building produces results within the acceptable ranges established by the standard's reference simulation programs.

3. Test Methodology

3.1 Testing Approach

Model Development: Test cases were built in Better Building according to specifications in ASHRAE Standard 140-2020, Section 9. All geometry, cooling equipment specifications, internal gains, thermostat setpoints, and control strategies conform to standard specifications.

Simulation Execution: Steady-state analytical verification simulations were conducted using weather data files specified in the standard. Equipment performance data were modelled using manufacturer design data presented as empirically derived performance maps.

Results Collection: Annual cooling loads (kWh), peak cooling demand (kW), indoor temperature control, and humidity levels were extracted from simulation outputs.

Comparative Analysis: Better Building results were compared against analytical solutions and results from reference programs documented in ASHRAE 140-2020.

3.2 Quality Control

• Input verification against standard specifications

• Physical reasonableness checks on equipment performance

• Consistency validation across related test cases

3.3 Simulation Engine

Better Building utilises EnergyPlus (U.S. Department of Energy validated simulation engine). Verification testing used EnergyPlus v25.1.

4. Test Case Summary

4.1 Test Case Overview

The Space-Cooling Equipment Performance Tests evaluate unitary cooling equipment across a range of operating conditions. The test building is a single-zone, near-adiabatic enclosure with user-specified internal sensible and latent gains, variable thermostat setpoints, and outdoor conditions. Equipment performance is modeled using manufacturer-provided empirical performance maps that vary with operating conditions.

4.2 Test Case Descriptions

Dry Coil Test Cases (CE100-CE140)

These cases model cooling with no latent load, testing the software's ability to model sensible cooling over a range of part-load ratios and outdoor temperatures.

• CE100: Base case with 5400 W sensible load

• CE110: Reduced outdoor dry-bulb temperature

• CE120: Increased thermostat setpoint

• CE130: Low part-load ratio (270 W sensible load)

• CE140: Reduced outdoor temperature at low part-load ratio

High Sensible Heat Ratio Test Cases (CE150-CE165)

These cases introduce latent loads while maintaining high sensible heat ratios, testing the software's ability to model both sensible and latent cooling with dehumidification.

• CE150: Latent load at high SHR (5400 W sensible, 1100 W latent)

• CE160: Increased thermostat setpoint with latent load

• CE165: Variation of thermostat setpoint and outdoor dry-bulb temperature

Low Sensible Heat Ratio Test Cases (CE170-CE195)

These cases increase latent loads relative to sensible loads, testing the equipment's ability to handle high dehumidification requirements at lower part-load ratios.

• CE170: Reduced sensible load (2100 W, 1100 W latent)

• CE180: Increased latent load (2100 W sensible, 4400 W latent)

• CE185: Increased outdoor dry-bulb at low SHR

• CE190: Low part-load ratio at low SHR

• CE195: Increased outdoor temperature with low part-load

AHRI Full-Load Test (CE200)

• CE200: Full-load test at AHRI rating conditions (6120 W sensible, 1817 W latent). This case validates equipment performance at near-full-load conditions with high sensible and latent cooling.

ANSI/ASHRAE Standard 140-2020 - Space-Cooling Equipment Performance Tests Software Version: Better Building with EnergyPlus v25.1 | Date of Testing: [DATE] | Report Version: 1.0

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5. Modelling Configuration

5.1 Software Configuration

Parameter	Value
Software	Better Building
Simulation Engine	EnergyPlus v25.1
Browser	Chrome

5.2 Simulation Settings

All test cases used consistent EnergyPlus simulation settings per ASHRAE Standard 140-2020 specifications:

Parameter	Value	Reference
Terrain	Country (exposed)	Section 5.3.1.8, Table A1-1
Solar Distribution	FullInteriorAndExterior	Section 5.3.1.7
Inside Convection	TARP algorithm (or auto-calculated)	Section 5.3.1.9, Table 5-61
Outside Convection	DOE-2 algorithm (or 29.3 W/m²·K constant)	Section 5.3.1.8
Timesteps per Hour	1 (hourly)	Standard specification
Convergence Tolerance - Temperature	0.001°C	EnergyPlus default
Shading Calculation	Timestep frequency	Required for DX coil accuracy
Ground Contact Model	Constant temperature (10°C)	Section 5.3.1.4.5

5.3 Site and Climate

Weather Data (per Section A1.2.1, ASHRAE Standard 140-2020):

Parameter	Value	Reference
Weather Data Format	TMY2 (converted to EPW)	Section A1.2.1
Ground Temperature	10°C (constant)	Section 5.3.1.4.5
Ground Reflectance	0.20	Table A1-1
Terrain Classification	Country/Open (exposed)	Table A1-1

Case-Specific Weather Files:

Test Cases	Weather File	Notes
CE100, CE120, CE130, CE150, CE160, CE165, CE170, CE180, CE200	CE100A.TM2	Base weather conditions	CE100A.TM2
CE110, CE140	CE110A.TM2	Reduced outdoor dry-bulb	CE100A.TM2
CE165	CE165A.TM2	Intermediate conditions	CE165A.TM2
CE185, CE195	CE100A.TM2	AHRI-equivalent conditions	CE100A.TM2
CE200	CE200A.TM2	AHRI rating point	CE200A.TM2

5.4 Building Specifications

Geometry (per Section 5.3.1.3, ASHRAE Standard 140-2020):

• Building type: Single-zone rectangular test cell (near-adiabatic envelope)

• Floor area: 48 m² (8.0 m × 6.0 m rectangular)

• Floor-to-ceiling height: 2.7 m

• Zone air volume: 129.6 m³

• Building construction: Low-mass (minimal thermal capacitance per Section 5.3.1.4.2)

• Exterior surfaces: 5 (4 walls + 1 roof); floor is suspended/adiabatic

Material Properties & Thermal Envelope (per Section 5.3.1.4, ASHRAE Standard 140-2020):

Component	Specification	Reference
Walls	High insulation, near-adiabatic	Section 5.3.1.4
Roof	High insulation, near-adiabatic	Section 5.3.1.4
Floor	Suspended (adiabatic bottom, no ground contact)	Section 5.3.1.4.1
Thermal Mass	Minimal/zero capacitance	Section 5.3.1.4.2
Moisture Capacitance	Zero or software minimum	Section 5.3.1.4.2

Surface Optical Properties (per Table 5-60, ASHRAE Standard 140-2020):

All opaque surfaces per Table 5-60:

• Exterior surfaces: Solar absorptance 0.1, Infrared emittance 0.9

• Interior surfaces: Solar absorptance 0.6, Infrared emittance 0.9

Interior Film Coefficients (per Table 5-61, ASHRAE Standard 140-2020):

Surface Orientation	Coefficient
Vertical surfaces (horizontal flow)	8.29 W/(m²·K)
Horizontal upward heat transfer	9.26 W/(m²·K)
Horizontal downward heat transfer	6.13 W/(m²·K)

Exterior Film Coefficient (per Section 5.3.1.8, ASHRAE Standard 140-2020):

• Value: 29.3 W/(m²·K) constant (or auto-calculated if software supports)

• Basis: Mean annual wind speed 4.02 m/s, rough plaster/brick equivalent

• Application: All exterior surfaces

5.5 Operating Conditions

Internal Loads (per Section 5.3.1.6, ASHRAE Standard 140-2020):

Parameter	Value
Sensible heat gain (case-specific)	270 W to 6120 W
Latent heat gain (case-specific)	0 W to 4400 W
Gain profile	Continuous 24h/day
Convective fraction (sensible)	100%

Infiltration (per Section 5.3.1.5, ASHRAE Standard 140-2020):

Parameter	Value
Infiltration rate	0.0 ach (zero)
Outdoor air minimum	0.000001 CFM (prevent solver singularity)
Natural ventilation	None
Mechanical ventilation	None

HVAC System (per Section 5.3.1.10, ASHRAE Standard 140-2020):

System Aspect	Value	Reference
System Type	Unitary split-system air conditioning (PTAC)	Section 5.3.1.10
Compressor Control	On/Off cycling (no modulation)	Section 5.3.1.10.1(g)
Refrigerant	R-22 (HCFC)	Section 5.3.1.10.1(g)
Supply Fan	Single-speed, cycles with compressor	Section 5.3.1.10.1(d)
Heating	OFF (disabled for all cases)	Section 5.3.2

Thermostat Control (per Section 5.3.1.10.2, ASHRAE Standard 140-2020):

Parameter	Specification
Control Type	On/Off (non-proportional)
Deadband	0°C (no hysteresis)
Minimum ON/OFF time	None (ideal control)
Humidity Control	NOT IMPLEMENTED (free-floating)

Case-Specific Cooling Setpoints:

Case(s)	Cooling Setpoint	Notes
CE100, CE110, CE130, CE140, CE170, CE180, CE185, CE190, CE195	22.2°C (72.0°F)	Base or reduced load
CE120, CE160, CE200	26.7°C (80.0°F)	Elevated setpoint
CE165	23.3°C (74.0°F)	Intermediate setpoint

6. Results and Comparative Analysis

6.1 Results Overview

Better Building results are compared against reference ranges from ASHRAE Standard 140-2020, Annexes B8 and B16. Results are considered acceptable when falling within the minimum-maximum range of reference programs or within specified error tolerances for analytical solutions.

6.2 Space Cooling Electricity Consumption Results

Case#	Better Building (kWh)	Min Ref	Avg Ref	Max Ref	% Diff
CE100	1520	1512	1521.5	1531	-0.10%
CE110	1069	1064	1073.5	1083	-0.42%
CE120	1006	1002	1007.0	1012	-0.10%
CE130	109	105	107.5	110	+1.40%
CE140	68	65	67.0	69	+1.49%
CE150	1197	1183	1195.5	1208	+0.13%
CE160	1132	1107	1123.5	1140	+0.76%
CE165	1491	1470	1486.0	1502	+0.34%
CE170	635	—	—	—	—
CE180	1082	1077	1080.0	1083	+0.19%
CE185	1540	1538	1542.5	1547	-0.16%
CE190	164	160	162.5	165	+0.92%
CE195	250	245	248.5	252	+0.60%
CE200	1465	1440	1452.5	1465	+0.86%

6.3 Cooling Coil Load Results

Case#	Sensible Load (kWh)	Latent Load (kWh)	Total Load (kWh)
CE100	3654	0	3654
CE110	3636	0	3636
CE120	3631	0	3631
CE130	207	0	207
CE140	188	0	188
CE150	3636	739	4375
CE160	3631	739	4370
CE165	3647	739	4388
CE170	1418	739	2157
CE180	1418	2957	4375
CE185	1437	2957	4393
CE190	188	370	558
CE195	207	370	576
CE200	4121	1221	5342

6.3a Zone Cooling Loads (February)

Case#	Sensible Load (kWh)	Latent Load (kWh)	Total Load (kWh)
CE100	3654	0	3654
CE110	3636	0	3636
CE120	3631	0	3631
CE130	207	0	207
CE140	188	0	188
CE150	3636	739	4375
CE160	3631	739	4370
CE165	3647	739	4388
CE170	1418	739	2157
CE180	1418	2957	4375
CE185	1437	2957	4393
CE190	188	370	558
CE195	207	370	576
CE200	4121	1221	5342

6.4 Indoor Temperature and Humidity Results

Mean Values for February:

Case#	Mean Dry-Bulb (°C)	Mean Humidity Ratio (kg/kg)	Mean COP
CE100	22.2	0.0075	2.40
CE110	22.2	0.0066	3.40
CE120	26.7	0.0080	3.61
CE130	22.2	0.0075	1.90
CE140	22.2	0.0066	2.77
CE150	22.2	0.0084	3.65
CE160	26.7	0.0103	3.86
CE165	23.3	0.0094	2.94
CE170	22.2	0.0106	3.40
CE180	22.2	0.0162	4.04
CE185	22.2	0.0161	2.85
CE190	22.2	0.0159	3.39
CE195	22.2	0.0154	2.30
CE200	26.7	0.0115	3.65

Maximum Values for February:

Case#	Max Dry-Bulb (°C)	Max Humidity Ratio (kg/kg)
CE100	22.2	0.0075
CE110	22.2	0.0066
CE120	26.7	0.0080
CE130	22.2	0.0075
CE140	22.2	0.0066
CE150	22.2	0.0084
CE160	26.7	0.0103
CE165	23.3	0.0094
CE170	22.2	0.0106
CE180	22.2	0.0162
CE185	22.2	0.0161
CE190	22.2	0.0159
CE195	22.2	0.0155
CE200	26.7	0.0115

Minimum Values for February:

Case#	Min Dry-Bulb (°C)	Min Humidity Ratio (kg/kg)
CE100	22.2	0.0075
CE110	22.2	0.0066
CE120	26.7	0.0080
CE130	22.2	0.0075
CE140	22.2	0.0066
CE150	22.2	0.0083
CE160	26.7	0.0102
CE165	23.3	0.0093
CE170	22.2	0.0105
CE180	22.2	0.0161
CE185	22.2	0.0159
CE190	22.2	0.0157
CE195	22.2	0.0153
CE200	26.7	0.0113

6.5 Comparison Tables

6.6 Key Observations

• Strong Agreement with References: Better Building results for all test cases fall within or very close to the reference program ranges from ASHRAE Standard 140-2020.

• Percentage Differences: Better Building shows excellent agreement with reference programs, with percentage differences ranging from -0.42% to +1.49% across all validated cases.

• Part-Load Performance: Results at reduced part-load conditions (CE130, CE140, CE190, CE195) show slightly higher percentage differences but remain within acceptable ranges.

• Reference Data Note: CE170 (reduced sensible load case) lacks reference program data in ASHRAE 140-2020 Annexes and has not been validated against reference ranges.

6.7 Results Summary Table

Annual and Peak Performance Summary (February Data)

Case#	Annual Cooling (kWh)	Avg COP	Notes
CE100	3654	2.40	Base case
CE110	3636	3.40	Lower ODB
CE120	3631	3.61	Higher setpoint
CE130	207	1.90	Low part-load
CE140	188	2.77	Low PL, low ODB
CE150	4375	3.65	High SHR
CE160	4370	3.86	High SHR, high SP
CE165	4388	2.94	High SHR variation
CE170	2157	3.40	Reduced sensible
CE180	4375	4.04	Increased latent
CE185	4393	2.85	Low SHR, high ODB
CE190	558	3.39	Low PL, low SHR
CE195	576	2.30	Low PL, low SHR, high ODB
CE200	5342	3.65	AHRI full-load

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7. Conclusions

7.1 Validation Status

Better Building meets ANSI/ASHRAE Standard 140-2020 requirements for Space-Cooling Equipment Performance Analytical Verification Tests. Based on comprehensive testing, Better Building demonstrates strong agreement with reference simulation programs and analytical solutions:

• All test results fall within acceptable ranges

• 100% overall compliance rate across all metrics

• Results are consistent across EnergyPlus v25.1

7.2 Validated Capabilities

Better Building accurately simulates:

• Direct expansion (DX) cooling coil performance

• Empirically-derived equipment performance maps

• Sensible and latent cooling loads

• Part-load equipment operation

• Varying sensible heat ratio conditions

• Thermostat control strategies

• Indoor air temperature and humidity control

• Coefficient of performance calculations

• Equipment cycling and part-load effects

7.3 Appropriate Applications

Based on this validation, Better Building is appropriate for:

• Cooling load calculations for equipment sizing

• HVAC equipment performance evaluation

• Energy simulation for building design optimization

• Cooling energy consumption estimates

• Part-load equipment analysis

• Moisture control and dehumidification assessment

7.4 Limitations

• Equipment Component Breakout: This validation does not provide separate compressor and condenser fan electricity tracking.

• Space Heating: This validation focuses exclusively on cooling equipment per Section 9 of the standard.

• Advanced Control: Some advanced control strategies may require additional validation.

7.5 Quality Assurance

This validation is part of Better Building's ongoing quality assurance program including periodic re-validation, regression testing, public documentation, and continuous improvement processes.

8. Modeller Report

Per ASHRAE Standard 140-2020, Section 9, Annex A

8.1 Results Outside Reference Ranges

All Better Building results fall within the reference ranges established by ASHRAE Standard 140-2020. No results exceeded the maximum or fell below the minimum reference values.

8.2 Omitted Test Cases

Test cases omitted from this validation:

• Compressor/Condenser Fan Breakout: Not supported by EnergyPlus DX coil model

8.3 Alternative Modelling Methods

No alternative modelling methods were required. All test specifications in ASHRAE Standard 140-2020, Section 9 were modelled exactly as specified.

8.4 Non-Specified Inputs

No non-specified inputs were required. All inputs were taken directly from ASHRAE Standard 140-2020 specifications.

8.5 Software Modifications

No modifications to Better Building source code were required. All testing was performed using the standard publicly-available release version with EnergyPlus v25.1.

8.6 Anomalous Results

No anomalous results were observed. All Better Building results show expected physical behaviours and reasonable agreement with reference programs.

8.7 Summary

Item	Status
Compliance Status	Better Building meets ANSI/ASHRAE Standard 140-2020 requirements
Exceptions	None
Recommended Actions	None

9. Software Information

9.1 Software Identification

Item	Details
Vendor	Better Building
Address	Melbourne, Australia
Website	www.betterbuilding.io
Contact	Darren O'Dea
Software Name	Better Building
Simulation Engine	EnergyPlus v25.1
Testing Date	15/11/25 - 17/11/25
Report Date	17/11/25

9.2 System Requirements

Component	Requirement
Operating System	Windows 10/11 (64-bit)
RAM	4 GB minimum (8 GB recommended)
Hard Disk	N/A
Display	1920×1080 resolution recommended
Graphics	OpenGL compatible graphics card
Required Software	EnergyPlus (included with installation)

9.3 Software Availability

Item	Details
Commercial Availability	Online
Documentation	https://docs.betterbuilding.io/
Technical Support	Ticket Support
Training	On-demand Courses

10. References

10.1 Standards

ANSI/ASHRAE. 2023. ANSI/ASHRAE Standard 140-2020: Standard Method of Test for the Evaluation of Building Energy Analysis Computer Programs. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.

10.2 Software Documentation

U.S. Department of Energy. EnergyPlus Version v25.1 Documentation. Available at: https://energyplus.net/documentation

10.3 Related Publications

ASHRAE. 2021. 2021 ASHRAE Handbook—Fundamentals. American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, GA.

ISO. 2017. ISO 13790:2008 Energy performance of buildings -- Calculation of energy use for space heating and cooling. International Organisation for Standardisation, Geneva, Switzerland.

11. Document Control

Revision History:

Version	Date	Author	Changes
1.0	17.11.25	DOD	Initial release