HVAC fundamentals and load calculations
Psychrometrics, heat gain, sizing and the design basics every commercial project starts from. 16 guides.
- Air density, altitude and HVAC design in Calgary and the Rockies
Learn how elevation changes air density, which HVAC calculations and selections need correction, and what to check when designing, balancing or commissioning systems in Calgary and mountain communities.
- Commercial cooling load calculations explained
Understand what goes into a commercial cooling load, how the ASHRAE methods handle time lag and storage, and how to review a load report before equipment is selected.
- Diversity and safety factors in load calculations
Learn the difference between diversity and safety factors, where each should be applied in a load calculation, and how stacked margins quietly produce oversized systems.
- Envelope heat loss: U-values, thermal bridging and infiltration
Learn how to calculate envelope heat loss accurately, why thermal bridges and air leakage often matter more than insulation thickness, and how these factors affect HVAC sizing.
- Heating load calculations for Canadian climates
Learn the components of a heating load, where Canadian design temperatures come from, and how to avoid the errors that leave buildings cold or with oversized boilers and heat pumps.
- Internal heat gains from people, lighting and equipment
Learn how people, lights and equipment add heat to a space, how to estimate each with realistic values and schedules, and why overestimating them leads to oversized systems.
- Part-load performance: why buildings rarely run at design
Learn why design conditions occur only a few hours a year, how part-load efficiency differs from full-load ratings, and how to select equipment and controls that perform well across the whole year.
- Psychrometrics for HVAC engineers: a practical guide
Learn the properties of moist air, how to read a psychrometric chart, and how to use psychrometric processes and equations to size coils, check humidity and troubleshoot systems.
- Refrigeration cycle basics for commercial HVAC
Learn how the vapour compression cycle moves heat, what superheat, subcooling and lift mean, how efficiency is measured, and why refrigerant choice and safety codes matter.
- Rules of thumb in HVAC sizing and why they fail
Learn where common HVAC sizing rules of thumb come from, why they fail for modern buildings, the real costs of oversizing, and the proper role of benchmarks in design review.
- Selecting outdoor design conditions for Canadian cities
Learn where Canadian outdoor design data comes from, what the percentage values mean, and how to pick heating, cooling and dehumidification conditions that suit the building's risk.
- Sensible and latent heat: why the ratio matters
Learn the difference between sensible and latent heat, how to calculate the sensible heat ratio, and why matching equipment to that ratio is the key to humidity control.
- Solar heat gain through glazing and how to control it
Learn how solar radiation enters buildings through glazing, how to read window performance ratings, and which glazing, shading and control strategies reduce cooling loads and glare.
- Thermal comfort and ASHRAE Standard 55
Learn what ASHRAE Standard 55 requires, how comfort depends on more than air temperature, and how to use the standard to design, commission and troubleshoot commercial spaces.
- Units and conversions every HVAC engineer uses
A practical reference for the units and conversion factors used daily in Canadian HVAC work, with the core air and water heat equations and tips to avoid common unit mistakes.
- Zoning a commercial building for HVAC
Learn how to group spaces into thermal zones that can be controlled properly, how zoning affects comfort and energy use, and the mistakes that cause persistent hot and cold complaints.