27 PB
COMPONENT TESTING
Capillary Tube Assy (Cool Only Units)
Test the Capillary Tube and Check Valve Assy
1. Check the capillary tube temperature by hand where the refrigerant enters the capillary tube. A partial restriction of
the capillary tube will be indicated by frost or freezing in that area.
2. If the capillary tube is fully restricted, then pressure will increase and pressure switch will open if installed. If
no pressure switch is installed, the unit will shut down due to the compressor overload opening. High discharge
temperature will be present at the compressor.
Indoor
Coil
(Evaporator)
Accumulator
Compressor
Outdoor Coil
(Condensor)
Cap Tube (Cooling Only)
Arrows Indicate Direction of Flow
Figure 501 (Cooling Only Regerant Flow)