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; the highest allowed temperature rise through the furnace is usually a 30° difference. When possible, we want to get the rise toward […]

Jacques Charles was a French physicist (and a real looker based on that photo) born in 1746. Little is known about his educational and family background, but he began his career as a clerk at the Ministry of Finance in Paris. After a short time as a financial clerk, he began focusing on science. The […]

We've been getting many questions on micron gauges that are ”going haywire” or reading in the micron range, even at atmospheric pressure. First, micron gauges measure absolute pressure, so you can’t ”zero” them out. They use tiny, very sensitive sensors that are calibrated to air, not refrigerant, so anytime refrigerant gets into the gauge, it's […]