There's a lot of talk about super heat charging and the way I charge a unit is by taking the indoor wet bulb and outside dry bulb but there's a lot of talk on relative humidity being a factor. On my charging chart it says " If under 20% RH or Over 70% RH use wet bulb ok but my friends at one of the largest A/C Heating companys in the mid west says he always uses indoor wet bulb. But if this is the case then why do charging charts have an option of using indoor dry bulb? when do i use the indoor dry bulb instead of the wet bulb? And Whats the deal with the Humidity 20% or over 70% on my chart. I think its going to take a true Tech to answer this because knowing the proper way is key to understanding what is supposed to be and figuring out how to understand the system for your self. I use wet bulb all the time, i do have an RH meter so if I knew when to use it and how it applies to my super heat method would be highly appreciated. Thanks HVAC-GUYS!!!