evaporator HONDA CIVIC 1998 6.G User Guide

Evaporator
1.
Replacement
4.
Move the temperature control to "HOl"
'96-98: Slide the temoerature control lever.'99-00: Turn the ignition switch ON (ll), then turn
the temperature contol knob. Turn the ignition
switch off.
Remove the battsry.
Rgcover the refrigerant with a rocovery/recycling/
charging station (see page 22-271.
Remove the bolts, then disconnect th6 suction 8nd
receiver lines from th6 evaoorator.
NOTE: Plug or cap the lines imm€diatoly after dis-
connecting them to avoid moisture and dust con-
tamination.
6xl.0mm9.8 n*ln ll.0 tg6m.7.2 lbt frl
RECEiVER UNE
Remove the glov6 box (see section 20).
Removo the self-tapping scr€w and the passeng€r's
dashboard lower cover. Removs the bolt. the nut
8nd the kn€e bolst6r, th6n r6mov6 th6 fiv6 bolts and
the glove box frame.
6.
srrcrrc u E
22-28
7. Disconnect the connector from th€ Ay'C thermostat,
and r€movs the wire harness from the ovaporator.
Remov6 tho four self-tapping screws, tho mounting
bolt and ths mounting nut. Disconnect th€ drain
hose, then remov€ th6 avagorator.
6 x l.0.nm9.8 l$m lt.o ldm, 7.2 bl.tt)
Install in the reverse order of removal. Make note of
th€ following items.
o lf you'r6 installing a new evaporator, add rofriger-
ANt OiI {SANDEN, SP-10 Or DENSO, ND-OIL 8)
lsas page 22-221.
. Replace the O-rings with now ones 8t 68ch titting,
and apply 8 thin coat of r€frlgersd oil before
installing them.
NOTE: Be sure to use the right O-rings for HFC-
134a (R-134a) to avoid loakago.
. Apply s€alant to tha grommets.
. Mske sure that ther€ is no air leakage.
. Chargs ths system {s€€ page 22-161, and tost its
performance (see pags 22-211.

Overhaul
1.
3.
Pull out the A,/C thermostat sensor from the evapo-
rator fins.
Remove the self-tapping screws and clamps from
the housings.
Carefully separate the housings, then remove the
evaporator.
lf necessary, remove the expansion valve.
NOTE: When loosening the expansion valve nuts, use
a second wrench to hold the expansion valve or the
evaporator pipe. Otherwise, they can be damaged
5. Assemble in the reverse order of disassembly Make
note of following items.
. Replace the O-rings with new ones at each fitting,
and apply a thin coat of refrigerant oil before
installing them.
NOTE: Be sure to use the right O-rings for HFC-
134a (R-134a) to avoid leakage.
. Install the expansion valve capillary tube so that
it is in direct contact with the suction line. Then
wrap wath taPe.
. Reinstall the Ay'C thermostat sensor to its original
location.
6th tin lrom inld side
Serpentine type:
Laminate typo:
TAPEReplace.lvake sure there is no foreign matter stuck between
60t5mml'2.1! O.2 inl
EVAPORATORblow din out of linswith compressed air,
HOUSING
8 N.m 10.8 kgt m,6 tbf.ftl
6th fin lrom outle't sideCAPILLARY TUAE
VALVEN
u'
ll
6\N.m (2.it kgt.m,17 tbtftl1l
A/C THERMOSTfesr page 22 21
%
EVAPORA
LOWER
22-29

- How the Circuit Works
'96198 Models
The air delivery system directs the flow of air used
by the heater and air conditioner systems.
Mode Selection
Mode selection is controlled by the mode switches
in the heater control panel and the mode control
motor. When you select a specific mode, voltage is
applied through the dimming circuit to the LED,
which comes on, indicating the mode selected.
Ground is orovided to the mode control motor
though that mode switch. The motor then runs until
the air control door reaches the proper position.
Fresh/Recirculation 56lection
When you press the fresh or recirculation button, a
ground signal is sent from the heater control panel
to the recirculation control motor. The motor then
runs until the recirculation door reaches the proper
position. Battery voltage is also applied through the
dimming circuit to the corresponding LED, and the
LED comes on.
Refer to the Service Manual (Section 21, Heater) for
specitic tests or troubleshooting proc€dures.
'99J00 Models
The heater control panel receives battery voltage at
all times through fuse 47. With the ignition switch in
ON (ll), voltage is supplied to the heater control
panel through fuse 17. The control panel is
grounded at G402.
The heater control panel controls the air delivery
motors, and supplies a 5 VDC reterence voltage to
the air mixture control motor.
The air mixture and mode control motors each
receive inputs trom the heater control panel. The air
mix motor regulates the mixture of cold and hot air
by varying the position of the heater-evaporator doot
The mode control motor controls the direction and
volume of outlet air. The air flow can be directed to
the dashboard vents or the corner vents.
Both the air mixture control molor and mode control
motor are grounded by the h€aler control panel.
The recirculation control motor receives battery
voltage through fuso 17 when the ignition swilch is
in ON (ll). lt regulates the position of the fresh/recirc
door, and is controlled by two position inputs from
the heater control panel ("Recirc" and "Fresh").
Refer to the Service Manual (Section 21, Heater) tor
specific tests or troubleshooting procedures.
61-3

- How the Circuit Works
Battery voltage is supplied through tuse 56 to the
A,/C compressor clutch r€lay contacts at all times.
With the ignition switch in ON (ll), vollage is applied
to the coil of the A,/C compressor clutch relay
through fuse 17. When you push the A,/C switch
ON, and the heater fan switch is in position | , 2, 3,
or 4, a "ground" input is provided to the engine
control module (ECM) or powertrain control module
(PCM) through the l'lC thermostat and the l'lC
pressure switch.
The A,/C compressor clutch relay is grounded by the
engine control module (ECM) or powertrain control
module (PCM). When energized, the A'lC
compressor clutch relay allows battery voltage to
turn on the A,/C comDressor clutch.
The A,/C ON indicator light comes on when the A,/C
system is requested.
A,/C Thermostat
The A'lC thermostat is located on the evaoorator
housing. The A,/C thermostat turns off the A,/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. The blower motor will keep running
when the sensor turns off the comDressor.
A,/C Pressure Switch
The fuC oressure switch is located in the condenser
outlet line where refrigerant is in a high
temperature/high pressure liquid state. The switch
will sense abnormally high or low pressure, and
open the circuit. This removes ground, and the
compressor will stop running.
Thermal Protectot
The thermal protector, located on the A,/C
compressor, opens and turns the compressor off if it
senses high temperature. Once the compressor
cools, the switch will close and the compressor will
begin running again.
Refer to the Service Manual (Section 22,
Air Conditioning) for specific tests or
troubleshooting procedures.
62-3

- How the Circuit Works
Radiator Fan
Voltage is provided at all times to the radiator fan
relay (contacts) through fuse 57. With the ignition
swilch in ON (ll), voltage is provided to the coil of
the relay through luse 17.
The radiator tan relay can be grounded through
either the engine coolant temperature switch or the
engine control module (ECM) or powertrain control
module (PCM).
The engine coolant temperature switch grounds
the radiator fan relay (coil) when the engine
coolant temperature exceeds 199'F (83'C). The
switch opens when coolanl temperature
decreases 3'- 8'C.
Condenser Fan
Voltage is provided at all times to the condenser fan
relay (contacts) through fuse 56. With the ignition
switch in ON (ll), voltage is provided to the coil of
the relay through fuse 17. When you push the A'lC
switch and put the heater fan switch in 1, 2,3, o( 4
position, the ly'C thermostat comes on, the
condenser fan relay energizes, and the condenser
fan motor runs.
A,/C Thermostat
The A,/C thermostat is located on the evaporator
housing. The A,/C thermostat tums off the A/C
compressor clutch if the temperature at the
evaporator goes below 3'C (37'F). This prevents
condensation from freezing on the evaporator fins
and blocking the air delivery into the passenger
compartment. lf the temperature goes below 3'C
(37"F) tuming off the Ay'C thermostat, ground will be
removed from the condenser fan relay. This will
deenergize the relay and remove voltage from the
condenser fan motor causing the fan to stop running.
Reter to the Service Manual (Section 23, Eleckical)
for specific tests or troubleshooting procedures.
63-3