HMMWV AC

1

• HMMWV A/C
• Tips to Prevent Damage to A/C System
• And
• Recommended Parts for Recovery
• from Battle Loss Vehicles

2
These main A/C Lines are exposed to Operators
during PMCS and are subject to damage due to A/C
components positioned on top of the engine where
all fluids are checked. Operators tend to climb
up on the engine to conduct a better PMCS.
Mechanics also will climb up on engine to tighten
fittings and bolts located in the engine
compartment. Soldiers need to be aware of the
location of these A/C components to prevent
damage resulting in leaks to the A/C system.
Discharge hose 4720-01456-8970
Suction hoses 4720-01-507-8678
3
The Dehydrator, located in the engine compartment
on the passenger side of the vehicle, can be
damaged by placing oil cans, tools and any heavy
object or parts used for maintenance.
Dehydrator hose 4720014568970
Discharge hose
4720-01456-8970
4720-01507-8678
A/C lines
4720015078679
4720014568970
4
The Manifold on the A/C compressor is mainly
damaged by operators and mechanics stepping,
leaning or placing objects on the A/C lines thus
causing the welds to break. The compressor is
located on the passenger side of the vehicle.
4720015078678
4720-01419-7754
4720-01-507-8678
4720014602436
Manifold and metal line parts of compressor
A/C lines
5
The A/C line hose clamp sometimes pulls the A/C
lines tight against the back end of the
generator. The placement of these hoses is a flaw
in the system. With the engine running the lines
create friction against the back end of the
generator causing the hoses to leak with time.
Adjusting the hose clamp to pull the hoses away
from the back end of the generator can prevent
the hoses from leaking.
A/C Lines hose clamp
AC lines
4720015078679
4720015078679
4720-01-456-8970
Point of friction
Discharge Hose 4720-265-3224
A/C Compressor 4720014568970
6
Damaged hose caused by friction against the back
end of the generator.
Damaged Hose
4720015078679
4720014568970
7
Leaky fittings are a result of fair, wear and
tear, but also caused by neglect. Operators and
Mechanics need to be aware of the location of A/C
hose fittings to prevent damage and leaks.
8
The A/C line going into the front evaporator,
show be low, is located on the front passenger
side. The A/C line is exposed and can be damaged
by stepping or placing large objects on the front
passenger floorboard. A cover over the A/C line
will protect it and prevent Soldiers from
accidentally damaging the system.
A/C line
9
The discharge line located behind the Drivers
side back seat has an elbow facing toward the
front and is exposed to damage. Secure the seat
so there is no movement forward or backward.
Loose seats can make contact with the elbow and
cause it to leak. Do not store objects behind the
seat. Objects move around and can accidentally
cause damage and leaks.
HMMV radiator for illustration purpose only
Discharge line elbow
Drivers side back seat
5930-01-516-9686
10
Checking battery power
11
Before operation check wires for proper connection
EMI Filter 4720-01-499-7635
When EMI filter or blower resistor goes bad
order 4720-01-499-7635
4720-01-499-7635
12
Check connection on battery and clean filter
weekly
4130-01-265-8691
13
During missions, if the fan fails to turn on,
disconnect the pressure switch and jump the wires
at the connector, then report this problem to
motor pool.
14
Operator checks PMCS
15
Operator During Operation Check
Does the clutch engage?
16
Parts and Components
17
M114 A/C SMART BOOK TIPS
Recommended Parts for Recovery from Battle Loss
Vehicles
Seven Primary Recoverable Parts
18
M114 A/C SMART BOOK TIPS

• A/C Air Compressor
• Before removing the air compressor system,
  recover the refrigerant.

Refrigerant 6830-01-390-9622
Compressor 4310-01-420-8306
19
M114 A/C SMART BOOK TIPS

• DRYER SWITCH
• UNSCREW SWITCH TO REMOVE.

5930-01-521-0167
20
M114 A/C SMART BOOK TIPS

• FAN A/C REAR CONDENSER
• REMOVE 4EA SCREW BRACKETS.

4140014565685
21
M114 A/C SMART BOOK TIPS

• A/C DE-ICE RELAY(BATTERY BOX)
• REMOVE NUT AND DISCONNECT WIRING.

5945014130886
22
M114 A/C SMART BOOK TIPS

• RELAY CONTROL MODULE FRONT
• REMOVE 1EA NUT AND WIRES.

5945014211784
5945014211785
23
M114 A/C SMART BOOK TIPS

• EVAPORATOR THERMOSTAT FLOW
• REMOVE 2EA BOLTS AND WIRES.

6685014213549
24
M114 A/C SMART BOOK TIPS

• IDLE PULLEY
• REMOVE 2EA BOLT AND LOOSE ADJACENT BOLT.
  

2920-01-420-7894
25
A/ C Electric Troubleshooting
26
A/C Electric troubleshooting (cont)
27
HMMV A/C Evacuation and Charge Procedures
28
HMMV A/C Pressure Diagnostic
29
HMMV A/C Pressure Diagnostic
30
HMMV A/C Pressure Diagnostic
31
HMMV A/C Pressure Diagnostic