Most techs know that you shouldn't fill a recovery tank more than 80% with liquid-based refrigerant. Many know that the WC rating stands for “water capacity” and that you need to adjust for the density of the actual refrigerant rather than just using 80% of WC. I hope most of you know that the TW […]

Double traps are no good. That's the end of this tech tip. Okay, here's some detail: Anytime your drain goes up and down more than once, you have a double trap UNLESS you place an air vent between the two traps that vents ABOVE the drain inlet. The double trap causes drainage issues because air […]

This article was written by Neil Comparetto. Neil is one of the smartest and most thoughtful techs I know online. Thanks, Neil. Why measure static pressure? Because it's fun. I enjoy drilling holes in things. I rarely leave a house without drilling a hole in something. I also believe it’s an essential step to commissioning […]