Engineering & Knowledge

Fundamentals & Engineering

Hvac Load Calculations

The accurate calculation of heating and cooling loads is essential to provide a sound bridge between fundamental building design decisions and an operating building. If loads are substantially underestimated, occupants and users will likely be hot or cold. If loads are substantially overestimated, equipment will be oversize (usually wasting money, reducing efficiency, increasing energy consumption, and often imperiling comfort).

Solar Angles – Fundamentals of Solar Positioning

Two fundamental parameters determine how effectively your solar panels capture sunlight: orientation and tilt. These factors, when properly calculated, can significantly increase your system’s efficiency and return on investment.

Understanding Solar Radiation: Earth’s Powerful Energy Source

Solar energy is the result of electromagnetic radiation released from the sun by the thermonuclear reactions occurring inside its core. All of the energy resources on earth originate from the sun (directly or indirectly), except for nuclear, tidal, and geothermal energy.

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Standards & Compliance

HVAC Ventilation Design: Lift/Elevator Pressurization

Complete guide to HVAC lift/elevator pressurization design using BS 5588-4 standards covering pressure control, airflow calculations, and elevator system integration for effective emergency vertical transportation protection.

HVAC Ventilation Design: Staircase Pressurization + Relief Vent Sizing

Complete guide to HVAC staircase pressurization and relief vent sizing design using ASHRAE and BS standards covering pressure control, airflow calculations, and relief system integration for effective emergency egress protection.

HVAC Ventilation Design: Corridor/Lift Lobby/Atrium Make-Up/Pressurization

Complete guide to HVAC corridor, lift lobby, and atrium make-up air and pressurization design using CIBSE and ASHRAE standards covering pressure control, airflow calculations, and fire safety integration for effective emergency protection.

HVAC Ventilation Design: Atrium Smoke Extract

Complete guide to HVAC atrium smoke extraction design using CIBSE and ASHRAE standards covering smoke layer management, extraction calculations, and advanced fire safety integration for large-volume space protection.

HVAC Ventilation Design: Corridor/Lift Lobby Smoke Extract

Complete guide to HVAC corridor and lift lobby smoke extraction design using CIBSE fire engineering standards covering smoke removal, pressure management, and life safety system integration for effective emergency ventilation.

HVAC Ventilation Design: Car Parking CO System

Complete guide to HVAC car parking CO detection systems using NFPA 720 standards covering carbon monoxide monitoring, alarm systems, ventilation integration, and safety protocols for parking facility protection.

HVAC Ventilation Design: Car Parking Make-Up Ventilation Rate By Velocity

Complete guide to HVAC car parking make-up ventilation design using ASHRAE velocity-based methods covering air movement calculations, system integration, and performance optimization for effective parking facility ventilation.

HVAC Ventilation Design: Car Parking Extract Ventilation Rate

Complete guide to HVAC car parking extract ventilation design using CIBSE and BS standards covering CO control, air change rates, and specialized applications for safe and efficient parking facility ventilation systems.

HVAC Ventilation Design: Commercial Kitchen Ventilation Rates (Hood/Canopy, Ceiling Extract/Makeup)

Complete guide to HVAC commercial kitchen ventilation design using ASHRAE, CIBSE, and VA standards covering hood exhaust rates, makeup air requirements, and specialized applications for effective contaminant control and energy efficiency.

HVAC Ventilation Design: Tobacco/Smoking Area Ventilation Rates

Complete guide to HVAC smoking area ventilation design using CIBSE standards covering high-performance ventilation rates, specialized system requirements, and health protection strategies for tobacco use areas.

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Digital Tools & Resources

Air Filters Efficiency Classification

ASHRAE 52.2: Filter testing was originated from America in 1930 (ASHVE and AFI code). It was then reviewed and modified in 1967 and 1968. ASRHAE collaborated with American National Standard Institude (ANSI) in 1992 to create ASHRAE-ANSI 52.1. Finally updated to ASHRAE 52.2 in 2007.

Psychrometric Programming Functions

ibrary of psychrometric functions to calculate thermodynamic properties of air for Python, C, C#, Fortran, JavaScript and VBA/Excel

Refrigerants in 2025: Properties, Applications, and Compatibility

As the HVAC and refrigeration industry continues to evolve with environmental regulations and technological advancements, understanding refrigerant properties remains crucial for engineers, technicians, and facility managers. This comprehensive guide provides an updated overview of common refrigerants, their compositions, and applications in today’s market.

Carrier Hap Software

Carrier’s Hourly Analysis Program is two powerful tools in one package – versatile features for designing HVAC systems for commercial buildings AND powerful energy analysis capabilities for comparing energy consumption and operating costs of design alternatives.

Trace 700 Software

TRACE 700 enables building designers to optimize the building, system and equipment designs on the basis of energy utilization and life-cycle cost. The Trane software for TRACE 700 facilitates analysis of the energy and economic effects of virtually any chiller plant configuration by allowing users to manipulate a wide range of variables and create a profile of their specific building.

Download EVAP-COND 5.0: The Ultimate Heat Exchanger Simulation Tool for HVAC Engineers

Whether you’re designing a new heat exchanger, optimizing an existing system, or researching alternative refrigerants, EVAP-COND provides the detailed analysis capabilities needed to make informed decisions. I encourage all HVAC engineers and researchers to explore this powerful simulation tool and experience firsthand how it can transform your approach to heat exchanger design.

Heat Transfer Textbook Download

The book is meant for juniors, seniors, and first-year graduate students. And to those who choose to learn the subject on their own, and to practicing engineers who use it as a reference. Whether one studies alone or with a class, learning means posing, then answering, one’s own questions.

Flexible Duct Calculator

Flexible Duct Calculator based on four different methods. Based on Friction Loss, Based on Duct Diameter, Equivalent Rectangular Duct, Equivalent Round Duct Diameter. Also table of Maximum Recommended Supply Velocity.

Air Change Cfm Calculator

The rate at which air is exchanged (in the premises) represents another method of measuring ventilation capacity & effectiveness. Air exchange rate is typically expressed in Air Changes per Hour – “ACH”. Air changes per hour can be estimated by determining the total air supplied to, and removed from, the premises “total air exchange” or the outdoor (fresh) air supplied to, and removed from, the premises “outdoor air exchange”. We invite you to experience how this calculator can transform your workflow. Whether you’re specifying a new system, troubleshooting an existing installation, or teaching the next generation of HVAC professionals, this tool was built with your needs in mind.

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