What is the pressure on the low side
R22 systems should run a 68# to 70# suction pressue. If you look at the suction guage at 68# that is a 40 deg evaporator coil temp.
There is no 1 temp, pressure to go by, the 40F coil is design condition with a 80F indoor and a 95F outdoor @ 50% humidity.
The more accurate ballpark method is actual ambient plus 30 degrees , convert to pressure for the outdoor unit, so the unit condenses at ambient plus 30 degrees, if a high efficiency unit with a huge condenser coil it may be + 25 rather than 30.Example: 95F ambient + 30F + 125 F , R-22 refrigerant @ 125F= 270#The indoor formula is indoor ambient - 40F convert to pressure.if much lower than 73 inside the coil will be below 32F and condensate will freeze! So you need to get the indoor above 73 minimum or charge to ambient - 40 and hope its ok.
And the sub cooling and super heat is important, 10 degree super heat a foot exiting the ac coil is design with no more than 20F superheat at the compressor as that helps cool it!
So you cannot simply charge every unit to 1 setting regardless of temps and humidity etc.
346 views
Usually answered in minutes!
×