HVAC Systems

Heating, Ventilation and Air Conditioning systems

Air Conditioning

Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort


Heating systems - capacity and design of boilers, pipelines, heat exchangers, expansion systems and more

Noise and Attenuation

Noise is usually defined as unwanted sound - noise, noise generation, silencers and attenuation in HVAC systems


Systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more

Acoustic Calculation of Ventilation Systems

Procedure for acoustic noise calculation of ventilation systems

Air-Duct Sizing

Air flow and required duct area

Calculating Indoor Temperature and Humidity Loads

Calculating sensible and latent heat from persons, lights, electric equipment, machines, evaporation from water surfaces, polluting fluids and miscellaneous loads

Dehumidification - Removing Moisture from Air

Principles of dehumidifying - cooling, adsorption or absorption

Fuels - Combustion Air and Flue Gases

Combustion air and flue gas for common fuels - coke, oil, wood, natural gas and more

Fuels - Exhaust Temperatures

Exhaust and outlet temperatures for some common fuels - natural gas, liquefied petroleum, diesel and more

Fuels - Higher Calorific Values

Higher calorific values for some common fuels - coke, oil, wood, hydrogen and others

Fuels and Chemicals - Auto Ignition Temperatures

The ignition point for some common fuels and chemicals butane, coke, hydrogen, petroleum and more

HVAC Diagram - Online Drawing

Draw HVAC diagrams - Online with the Google Drive drawing tool

HVAC Terms

Definition of some common HVAC industry terms - absolute humidity, pressure, temperature and more

Heat, Work and Energy

Heat, work and energy tutorial - essentials as specific heat

Humidifying Air with Steam - SI units

Use steam to humidify air

Introduction to Psychrometry

An introduction to air psychrometrics

Maximum Duct and Pipe Sizes through Steel Joists, K-series

Joists and maximum size of ducts and pipes

Moisture Transport through Building Walls and Roofs

Moisture will flow through a wall or roof if the vapor partial pressure is higher on one of the sides

Natural Gas Consumption

Natural gas consumption in common equipment - boiling pans, ovens, cookers, kettles and more

Optimal Combustion Processes - Fuels and Excess Air

Stable and efficient combustion conditions require correct mixtures of fuels and oxygen

Outdoor Temperature and Relative Humidity - US Winter and Summer Conditions

Outdoor design temperature and relative humidity in US states and cities - summer and winter

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