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System Pressures
Technicians with R-22 experience will need to become familiar working with high and 
low side pressures that are much higher when using R-410A.  A typical R-22 system 
operates normally with a high side pressure of approximately 260 psi @ 120°F 
condensing temperature and a low side pressure of approximately76 psi @ 45°F 
evaporator saturation temperature.
A normally operating R-410A system with the same condensing temperature of 
120°F and 45°F evaporator saturation temperature will have a high side pressure of 
approximately 500 psi and a low side pressure of approximately 150 psi.
•  5/16-in. socket or drive
•  1/4-in. socket or drive: Ground screws and control assembly use 1/4-in. machine thread screws
•  3/8-in. socket or drive: For outdoor fan blade removal 
•  4-mm Allen wrench: For indoor fan blade removal
•  Volt Ohm Meter
•  Amp probe
•  Needlepoint meter leads
•  Sealed system and R-410A recovery equipment
•  Thermal paste (Part #: WX5X8927)
•  Extension needed for condenser shroud screws
Tools Required
  Caution