The topic of static pressure comes up frequently in HVAC, and it’s sometimes presented as a test that can be all-knowing and insightful about what is happening with regard to airflow in a system. To use static pressure responsibly, we need to understand what it really is and what it means for an HVAC system. […]

There is a common belief in the trade that the higher the subcooling, the better the system efficiency because lower liquid line temperature means less flash gas. This statement is only partially true and can lead to some confusion among techs. Subcooling is a temperature decrease below the condensing temperature of the refrigerant that occurs […]

Low pressures are often measured in inches of water column or “WC. Like most units of measure, it has a very simple origin; in a water manometer, 1″ of water column is literally the amount of force it takes to raise the column of water by 1”. While some water manometers (water tubes) are still […]