Take a look at the screenshots above. The one on the left is for Death Valley at 282′ below sea level, and the one on the right is Denver, CO, at 5,280′ above sea level. Notice the barometric pressure values; they are almost the same. That means that barometric pressure is corrected or “normalized” to […]

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 […]

In residential air handler/fan coils, it is common to use a high-voltage interlock between the blower and the electric heat strips to ensure that the blower comes on whenever the heat is on. The problem is that it CANNOT work the other way around where the heat comes on with the blower. Heat strips are […]