Monaco Cayman 2005 Owner's Manual page 310

High pressure readings are another way to determine the amount of charge. The ambient tem-
perature reading is measured one inch away from the condenser. The ambient temperature reading,
plus 40° F, will equate to a value from the pressure table.
EXAMPLE:
90° F. 1 inch from condenser + 40° F = 130° F ----- 198.90 PSIG -
On fully charged system the expected pressure that should be seen on the
HIGH-SIDE gauge will be around 200 PSIG.
NOTE:
All systems are charged at the factory with 4.0 lbs of R134a. A fluorescent dye has
been added for leak detection.
R-134a Refrigerant:
R134a is classified non-explosive, non-flammable and non-corrosive.
R134a is ozone friendly; however, it is not technician friendly. Proper care in handling must be
observed. Under normal atmospheric pressures and temperatures R134a will evaporate so quickly it will
freeze anything it comes in contact with. The open container boiling point for R134a is minus 21.7º F.
This low boiling point makes for an ideal refrigerant. The tremendous amount of heat transfer which
occurs when a liquid boils, or vapors condense, forms the basic principle of all A/C systems. The
amount of heat required to raise or lower the temperature of one pound of water by 1º F equals one
British Thermal Unit (BTU). The BTU is the standard measurement of an air conditioner system.
310
Section 9 --- Electrical Systems - Chassis
psi gauge_temp.eps
Cayman 2005