About Refrigerants; Chemical Stability - Monaco DIPLOMAT 2004 Owner's Manual

DIPLOMAT 2004

About Refrigerants

9 •346

Chemical Stability:

The air conditioning system life and efficient operations depends upon the
chemical stability of the refrigeration system. The refrigeration system is
made of Refrigerant-R134a and Polyakylene Gycol (PAG) synthetic
lubricant. It is very important that all materials contained within the
refrigerant system be chemically compatible.
The only suitable compound for use with R134a is PAG. The total amount
of PAG within the refrigerant system is approximately 18% of the total
refrigerant in the system.
How much refrigerant is in the system? How much should be used when
charging? You will need 1 oz. of PAG for each 7 feet of hose after the first
15 feet of hose. Roughly, a 40 foot motorhome will use 92 feet of refrigerant
hose. Take 15 feet off the measurement and the result would be 77 feet. This
77 feet is then divided by 7 for total of 11. This represents the number of
ounces of PAG oil needed for the A/C system (11 oz.).
Carrying the formula one step further, the 11 oz. equal approximately
18% of the entire system. The total will equate to approximately 61 oz. or
3.8 lbs. of R134a.
High pressure readings are another way to determine the amount of
charge. The ambient temperature 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.
ELECTRICAL SYSTEMS - CHASSIS