Mooney M20V - Page 148

MOONEY INTERNATIONAL CORPORATION
M20V SERVICE AND MAINTENANCE MANUAL
Page
Date
9
MAR 2017
Rev Date
2. Remove, if required, any enclosures or access
doors to expose all tubing, hoses, fittings, etc. to the
compressor- condenser module/evaporator module.
3. Verify all aircraft and/or ground power is OFF.
4. Remove service port caps from A/C system. Ac-
cess to service ports is through Avionics Bay access
panel, LH side of Tailcone.
-CAUTION-
Compressor and receiver- dehydrator may be
pressurized by manufacturer with Nitrogen
gas. Open factory installed caps & plugs
carefully.
5. Close all manifold gauge valves and verify hose
connections are tight.
6. Connect R-134a refrigerant charging manifold.
R-134a service gauges contain quick- connect fittings
to minimize refrigerant loss. To install quick- connect,
push on firmly until locked (a ”clicking” sound is heard).
Hold grip ring and pull to remove quick- connect fit-
tings.
7. Connect charging manifold YELLOW hose to a
regulated dry nitrogen source.
-NOTE-
An adapter is required to connect yellow charg-
ing hose to nitrogen source.
-CAUTION-
Do not exceed 200 PSIG nitrogen pressure
during leak check procedure or damage to
expansion valve WILL result.
8. Regulate nitrogen source to a pressure of 200
PSIG maximum.
9. Remove all shrouds, panels, flooring and any oth-
er covering which prevents access to refrigerant fittings
or connections (if required).
10. Verify all plumbing connections are secure.
-CAUTION-
During this procedure protective eye wear
and gloves should be worn to prevent opera-
tor injury.
11. Slowly open high pressure (RED) manifold valve
and allow system pressure to increase gradually until a
pressure of 200 PSIG is achieved. Allow time for sys-
tem pressure to equalize across expansion valves.
Note final system pressure.
12. Apply soapy leak check fluid to each connection
to locate leaks.
-CAUTION-
Do not use any leak dye in R- 134a system or
damage to system may result.
13. Use thread sealant on all male fitting threads
(sparingly), staying off the first two (2) threads near
sealing surface. A light coating of R- 134a refrigerant
oil must be applied to flare and/or o- ring to prevent
metal galling/o- ring damage.
-NOTE-
Do not apply oi l to fitting threads.
-CAUTION-
Do not over tighten plumbing connections.
Stripped threads or cracked flares may result.
14. Tighten joints as necessary to stop leaks.
-CAUTION-
Vent system pressure very slowly to assure
that compressor oil is not vented with the ni-
trogen. Do not PERMIT air to enter the
system.
15. With system leak tight, turn nitrogen source OFF;
disconnect YELLOW charging hose from nitrogen
source and slowly release nitrogen pressure to zero.
16. Close manifold valve.
17. Replace all panels, doors and shrouds removed
for procedure.
21-52-00 - SYSTEM R- 134a EVACUATION AND
CHARGING PROCEDURE
Charging the refrigerant (R-134a) system is required
on new system installations, after an accidental line
break, component failure or when the system has ex-
cessive leaks. Due to the chemical nature of the refrig-
erant, every precaution must be taken to protect the
service person from accidental exposure to the refrig-
erant. See service precautions in Section 21-59-00.
Only R-134a refrigerant must be used or damage to the
system will result. Overcharging the system with refrig-
erant and/or oil will also result in system damage or re-
duction in performance and service life. The compres-
sor is pre- charged with 5 oz. of ESTER RL- 500S air
conditioner oil. No additional oil is required to be added
to a new system.
21-52-01 - SPECIAL TOOLS AND/OR EQUIP-
MENT REQUIRED
The following tools and equipment are required to
charge the refrigerant system:
1. Small hand tools and socket set
2. Vacuum pump, air or electric (0- 30 in. hg.)
3. Refrigerant, R- 134a, 30 lb. cylinder
21-52-00