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charging a/c systems?
iwas into hvac 15 years or so ago but i seem to rembember adding 30 degrees to something maybe the outside air temp for the right pressure to refridgerent reading/ any help you be nice or iam getting old its for r-22
3 Answers
- 9 years agoFavorite Answer
On the inside of the door will be a chart. If unit has a txv, then charge per the subcooling chart. If no txv, charge to the superheat chart. If theres no chart, use 10 deg. The 30 deg your referring to is the head pressure should corespond to 30 deg above outdoor ambient temp, however this is not a charging meathod
Source(s): Hvac tech - jusviciousLv 49 years ago
You are somewhat correct. This is done for the high side reading only. First get the outside air temp. Add 30 degrees for forced air to the outside temp. Now on your R-22 scale on the high gauge find the total temp on the gauge. This on average will be your high side head pressure. Hope this answers your question.
Source(s): Hvac Tech - JamesLv 79 years ago
Put a thermometer in the vent. At 52F it is considered right. At idle with the fan on. Takes a while to get there. And use a can with a pressure gage on it. Not a AC. person. But that is were the company use to set all company vehicles at on AC. in the shop for maximum life. And not be prejudice against any one.
