This article was written by Michael Housh, owner of Housh Home Energy and a regular contributor to HVAC School. Thanks, Michael! This is another article in trying to relate the air side of HVAC with the water side. In this article, I’m going to talk about how to determine pump flow (GPM) based on the […]

Every gas furnace data plate/tag has a specification for the temperature rise through that furnace. It is shown in a range, like 50-80° or 45-75°. Those two numbers are the lowest recommended temperature rise, and the highest allowed temperature rise through the furnace is usually a 30° difference. When possible, we want to get the rise […]

We have been discussing many methods for checking a refrigerant charge without connecting gauges over the last few months. This got me thinking about the “approach” method of charging that many Lennox systems require. The approach is simply how many degrees warmer the liquid line leaving the condenser is than the air entering the condenser. […]