Engineering & Knowledge

Fundamentals & Engineering

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.

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.

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.

Belimo SelectPro – Free Download

Download SelectPro desktop app free. Size and select valves, actuators, and sensors with export builder, quote generator, and centralized reference documents. For HVAC engineers and contractors.

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.

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.