Friedrich FPHMR18A3A Service Manual page 110

R-410A SEALED SYSTEM REPAIR
Pumping Down
– Remove the valve stem caps and confirm that the valve stems
are in the raised position.
– Be sure to use a hexagonal wrench to operate the valve stems.
– Connect the charge hose with the push pin to the service port.
– Open the low-pressure valve on the charge set slightly to air
purge from the charge hose.
it when the gauge indicates 14 psi.
110
Indoor unit
Lo
CLOSE
Purge the air
Liquid side
Open
2-Way
valve
Gas side
Open
3-Way
valve
CLOSE
– Do this quickly so that the gauge ends up indicating 0-15 PSI.
– Tighten the service port nut.
– Be sure to check for gas leakage.
Outdoor unit