“Isaac Newton” by paukrus is licensed under CC BY-SA 2.0 Sir Isaac Newton was an English physicist and mathematician born in a small Lincolnshire village called Woolsthorpe in 1642. His father died before he was born, and his mother remarried when Newton was three years old. He stayed with his maternal grandparents thereafter, and his […]

Relays can be used for many different control applications, including controlling fans, blowers, other relays, or contactors, valves, dampers, pumps, and much more. A 90-340 is a very common, versatile relay that many techs have on their truck. So, we will use it as an example. A relay is just a remotely controlled switch that […]

Yeah? Well, how do you know? What should they be? What are the outdoor and return air temperatures? What SEER rating is the equipment?  These are the questions I ask every single time a technician says the phrase,  “But the pressures look good for [insert refrigerant of choice here].”  When they can’t answer the questions […]