Engineering & Knowledge

Fundamentals & Engineering

Fans: The First Line Of Cooling

Fans, Just as with windchill in the winter, moving air will quickly reduce our skin temperature, especially when the evaporation of perspiration is included. Even homes that use air conditioning can benefit from the use of fans. Cooling our bodies with a fan means we can turn up the temperature for the air conditioner, and save energy overall. Different type of fans: Portable Fans, Box Or Window Fans, Ceiling Fans, Whole-House Fans, Attic Fans. #fans #Portablefans #box fans #CeilingFans #WholeHouseFans #AtticFans #Destratification

Ductwork Air Flow Balancing

Balancing air systems (ductwork) may be accomplished in various ways. The most common method to accomplish ductwork balancing is Proportional Method. Each diffuser is adjusted to supply the right percentage of total air volume in the ductwork.

Hvac Career Opportunities

The HVAC/R (heating, ventilating, and air conditioning / refrigeration) industry is rapidly changing due to advancements in technology being spurred on by the need for increased energy efficiencies. Accordingly, the career opportunities open to an individual seeking employment in HVAC fields can be divided roughly into four categories, each dependent upon a different type or degree of education and/or training.

Valve Characteristics

Why do we need to be aware of the valve characteristics? Every component in a hydronic system has some level of influence on the control and performance of a hydronic system. Valves are key because they are the controlling devices at the critical areas of heat transfer.

Major Hvac Systems and Equipment

A comprehensive list of all the major HVAC system types and related equipment

Copeland Refrigeration Manuals Download

This is a five series of publications comprising the Emerson Climate Technologies, Inc. Refrigeration Manual. Although each separate part covers a specific area of refrigeration theory and practice, each successive publication presumes a basic understanding of the material presented in the previous sections.

Refrigerant Piping Requirements

This guide focuses on systems that use Refrigerant-22 (R-22). While the general requirements are the same for systems that use other refrigerants, velocities and pressure drops will differ.

Ice Storage Systems

Thermal energy storage (TES) involves adding heat (thermal) energy to a storage medium, and then removing it from that medium for use at some other time. This may involve storing thermal energy at high temperatures (heat storage) or at low temperatures (cool storage).

Life Cycle Cost Analysis Method

The life-cycle cost analysis method is the most commonly accepted method to assess the economic benefits of energy conservation projects over their lifetime. Typically, the method is used to evaluate at least two alternatives of a given project (for instance, evaluate two alternatives for the installation of a new HVAC system: a VAV system or a heat pump system to condition the building). Only one alternative will be selected for implementation based on the economic analysis.

Hvac Air Volume Calculation

The air volume for an HVAC system is calculated from the sensible heat in the conditioned space. For the typical heating and cooling unit, the calculation is for cooling because more air is needed to cool a space than to heat it. If the conditioned space can be properly cooled with a given amount of cfm, then the space can be heated correctly with the same amount of cfm.


Standards & Compliance

HVAC Duct Design: Duct Fittings Friction Loss

Complete guide to HVAC duct fittings friction loss using Carrier standards covering loss coefficients, pressure drop calculations, and system optimization for efficient air distribution design.

HVAC Duct Design: Dampers, Attenuators, and Coils Friction Loss

Complete guide to HVAC dampers, attenuators, and coils friction loss using SMACNA standards covering pressure drop calculations, component selection, and system optimization for efficient air distribution design.

HVAC Duct Design: Duct Round to Rectangular Equivalent

Complete guide to HVAC round-to-rectangular duct equivalency using ASHRAE standards covering conversion formulas, performance considerations, and system optimization for space-constrained installations.

HVAC Duct Design: Duct Friction Loss

Complete guide to HVAC duct friction loss calculations using ASHRAE standards covering friction charts, pressure drop analysis, and system optimization for efficient air distribution design.

HVAC Duct Design: Duct Pressure Classification

Complete guide to HVAC duct pressure classification using SMACNA standards covering pressure class selection, construction requirements, and testing protocols for safe and efficient ductwork systems.

HVAC Duct Design – Sizing Contaminant-Extraction Ducts (Smoke | Grease | Gases | Dry & Moist Dust)

ASHRAE’s Pocket Guide lists minimum conveying velocities that keep contaminants airborne while they travel through exhaust ductwork. Table 2.9 (2013 edition, Ch. 02, pp. 60

HVAC Duct Design: Commercial Kitchen Duct Sizing

Complete guide to commercial kitchen duct sizing using ASHRAE and NFPA standards covering exhaust hood design, grease management, fire safety, and make-up air systems for food service operations.

HVAC Duct Design: Duct Sizing by Velocity & Noise Criteria (NC)

Complete guide to HVAC duct sizing using velocity and noise criteria with ASHRAE and CIBSE standards covering acoustic design, velocity limits, and noise control for sensitive applications.

HVAC Duct Design: Duct Sizing by Equal Friction Method

Complete guide to HVAC duct sizing using the equal friction method with SMACNA and ASHRAE standards covering calculation procedures, friction rate selection, and system optimization for effective air distribution design.

HVAC Duct Design: Duct Sizing SMACNA Recommendations

Complete guide to HVAC duct sizing using SMACNA recommendations covering equal friction, velocity, and static regain methods with design calculations and system optimization for effective air distribution.


Digital Tools & Resources

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.

HVAC-R Load Calculator: Your Essential Tool for Accurate System Sizing

Our new web-based calculator combines sophisticated engineering principles with an intuitive interface, making accurate load calculations accessible to everyone from students to seasoned professionals. Unlike basic square-footage estimators, our tool considers the multitude of factors that influence heating and cooling requirements.

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