Engineering & Knowledge

Fundamentals & Engineering

Thermal Storage (HVAC)

Thermal energy may be stored in three main ways: – Sensible Storage – Latent Storage – Thermo-Chemical Storage. In addition, the two common thermal storage strategies employed are: – Load Levelling Strategy – Load Shifting Strategy

Hydropneumatic Tank Sizing

Hydropneumatic tanks are primarily used in a domestic water system for draw down purposes when the pressure booster system is off on no-flow shutdown (NFSD). The NFSD circuitry turns the lead pump off when there is no demand on the system. While the system is off in this condition, the hydropneumatic tank will satisfy small demands on the system. Without the tank, the booster would restart upon the slightest call for flow such as a single toilet being flushed or even a minute leak in the piping system. Hydropneumatic tank sizing is dependent on two factors: – Length of time you wish the pumps to remain off in a no-flow situation. – The tank location in relation to the pressure booster.

Pump Sizing Core Concepts

Pump sizing involves matching the flow and pressure rating of a pump with the flowrate and pressure required for the process. The mass flowrate of the system is established on the process flow diagram by the mass balance. Achieving this mass flowrate requires a pump that can generate a pressure high enough to overcome the hydraulic resistance of the system of pipes, valves, and so on that the liquid must travel through. This hydraulic resistance is known as the system head.

Hvac Equations (U.S./Metric)

The heating, ventilation, and air conditioning (HVAC) equations. In both U.S. and Metric units.

Expansion Tanks

How does Boyle’s law relate to sizing expansion tanks in domestic hot water systems? what size expansion tank is required?

Expansion Tank Sizing Formulas

Expansion tanks are a necessary part of all closed hydronic systems to control both minimum and maximum pressure throughout the system. A comprehensive review of tank types and sizing procedure for expansion tanks.

Primary Secondary Pumping

– What is Primary-Secondary Pumping? – PRIMARY-SECONDARY BASICS. – PRIMARY-SECONDARY RULES, DEFINITIONS. WHEN TWO PIPING CIRCUITS ARE INTER-CONNECTED, FLOW IN ONE WILL CAUSE FLOW IN THE OTHER, T0 A DEGREE DEPENDING UPON THE PRESSURE DROP IN THE PIPING COMMON T0 BOTH.

4-Pipe And 2-Pipe Heating And Cooling Plants

A 4-pipe heating and cooling plant contains both central heating and cooling equipment and is capable of delivering heating water and chilled water to the building simultaneously through four pipes (one heating water supply, one heating water return, one chilled water supply, and one chilled water return). Heating and cooling equipment within the building that is connected to a 4-pipe system will have four pipe connections, unless the equipment provides either heating only or cooling only. In this case, the equipment would have only two pipe connections.

Constant Air Volume (CAV) Systems

HVAC air systems can be either centralized or decentralized. Centralized air systems receive their cooling and heating energy from a remote central plant. Decentralized HVAC air systems contain the central heating and cooling plant equipment within the air system itself. HVAC air systems can also be constant air volume (CAV) or variable air volume (VAV). CAV systems deliver constant supply airflow at a variable temperature. VAV systems deliver variable supply airflow at a constant temperature. CAV and VAV air systems can be further subdivided into systems that condition a single temperature zone and systems that condition multiple temperature zones.

Pump Construction (Part1)

In 1689 the physicist Denis Papin invented the centrifugal pump and today this kind of pump is the most used around the world. The centrifugal pump is built on a simple principle: Liquid is led to the impeller hub and by means of the centrifugal force it is flung towards the periphery of the impellers. The construction is fairly inexpensive, robust and simple and its high speed makes it possible to connect the pump directly to an asynchronous motor.

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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

Rates Of Thermal Expansion For Common Pipe Materials

Effortlessly calculate rates of thermal expansion for common pipe materials with our interactive calculator. Get accurate data, design insights, and actionable tables for metals and plastics—essential for HVAC engineers, designers, and consultants focused on system reliability and energy efficiency.

HVAC Equipment Life Expectancy Calculator

We’ve created a professional HVAC equipment life expectancy calculator. The application provides comprehensive calculations for determining the remaining useful life of various HVAC equipment types.

BIM Software Solutions for Modern HVAC Applications

As the HVAC industry continues to evolve in 2025, Building Information Modeling (BIM) has become an indispensable tool for professionals seeking to optimize design, installation, and maintenance processes. For HVAC engineers, contractors, and technicians, selecting the right BIM software can significantly impact project efficiency and outcomes. Let’s explore the most effective BIM solutions for HVAC applications.

Mcquay Softwares Download

McQuay (As part of Daikin Industries) is one of the largest air conditioning, heating, ventilating and refrigeration companies in the HVAC/R industry. Therefore, we decided to make some softwares that this company has introduced to the industry based on their experience and knowledge available for download.

Bell & Gossett Selection Softwares

#Xylem Bell & Gosset #Selection, #Sizing & #CAD Tools and #Softwares

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.

Pipe Schedules Tables

Pipe Schedule (SCH) is a standard that measures the nominal wall thickness of a pipe. The pipe schedule number is non-dimensional and depends on the nominal pipe size, internal pipe working pressure, and the material used for the pipe wall.

Piping Tools (Excel Files)

More than 165 spreadsheets (excel xls files) for a comprehensive range of calculation in Fluid, Thermal and piping engineering.

Daikin Revit Files

DAIKIN APPLIED RESOURCE LIBRARY – REVIT FILES Rooftop Systems Air Handlers – Outdoor Air Cooled Chillers Water Cooled Chillers Fan Coils Self-Contained Water Source Heat Pump Unit Ventilators

Cooltools Software Download

– Cycle analysis (process design) – comparison of one stage direct expansion cycle and one stage flooded cycle. – System sizing – calculation of component sizes from general criteria. – System simulation – calculating operating conditions in a system with known components. Component calculations – calculation of – components efficiencies and outlet conditions. – Evaluation of operation – evaluation of system efficiency. – Process investigation – e.g. moist air calculations.