Monarch SE 2004 - About Refrigerants

326 | Section 8 Electrical System ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ----------------- Monarch SE 2004
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 pres-
sure 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.
About Refrigerants