Carrier | 38SQ100 | Installation Instructions

38SQ
Control Box
Modification Kit
Installation Instructions
Part No. 315776-701, -702, -703, -704, and -705
NOTE: Read the entire instruction manual before starting the
installation.
INTRODUCTION
The following procedure is for field modification of the electrical
controls in the compressor section of a 38SQ triple-split heat pump
with the A, O, and R microprocessor board. The modification
consists of removing the existing control box and installing the
new control box with a standard time/temperature defrost control
board.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause personal injury or property damage.
Consult a qualified installer, service agency, or your distributor or
branch for information or assistance. The qualified installer or
agency must use factory-authorized kits or accessories when
modifying this product. Refer to the individual instructions packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses and work gloves. Use
quenching cloth for brazing operations. Have fire extinguisher
available. Read these instructions thoroughly and follow all
warnings or cautions attached to the unit. Consult local building
codes and National Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety-alert symbol
.
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal words DANGER, WARNING, and CAUTION. These words are used with the safety-alert symbol. DANGER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards which
could result in personal injury or death. CAUTION is used to
identify unsafe practices which would result in minor personal
injury or product and property damage.
Before servicing or modifying system, always turn off main
power to system. There may be more than 1 disconnect
switch. Turn off accessory heater power if applicable. Electrical shock can cause personal injury or death.
3. Remove access wrapper and top cover.
4. Disconnect crankcase heater wires and remove wires from
control box. Do not remove crankcase heater from compressor.
5. Remove compressor terminal box cover and disconnect compressor wires. Do not damage or disturb the fusite plug.
6. Remove thermostat wires from compressor section defrost
board in compressor section. Label wires for ease of connection to terminal board. (See Fig. 1.)
THERMOSTAT
SUBBASE
HH93AZ183 OR
HH93AZ186
38SQ
40QB, 40AQ, OR 40FQ
COMPRESSOR ELECTRIC HEATER
SECTION TERMINAL
TERMINAL
BOARDS
BOARD
R
R
R
R
C
C
C
C
Y
Y
G
G
G
G
W2
W2
O
O
E
E
P
P
W3
W3
E
EL
W2
W2
L
24 V
TRANS
38SQ
OUTDOOR COIL
CONTROL BOX
T
T
DFT
DFT
DFT
COOLING AND 2-STAGE HEATING
WITH ELECTRIC HEAT
BEFORE MODIFICATION
A92322
Fig. 1—Wiring Prior to Modification
Refer to Fig. 2 to assist in completion of the following steps.
7. Disconnect defrost thermostat wires and remove from control
box.
8. Disconnect wires to reversing valve solenoid coil.
As with any mechanical equipment, personal injury can result
from sharp metal edges. Take care when removing parts.
MODIFICATION PROCEDURE
Step 1—Remove Factory-Installed Control Box
1. Turn off power to the compressor section and indoor air
handler.
2. At wire nuts, disconnect line power wires from wires to
secondary disconnect.
9. Disconnect wires to low-pressure switch (LPS) and remove
from control box.
10. Disconnect wires to outdoor fan motor and remove from
control box.
11. Remove control box mounting screws and remove box.
Step 2—Install Control Box Modification Kit
1. Mount modified control box using screws removed from old
control box. (See Fig. 3.)
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101
Catalog No. 563-782
Printed in U.S.A.
Form 38SQ-19SI
Pg 1
6-94
Replaces: 38SQ-18SI
Tab 5a 5a
Table 1—Control Box Modification Kits
UNIT
38SQ024-3
38SQ030-3
38SQ036-3
38SQ042-3
38SQ048-3
5. Route wires from defrost thermostat into control box and
connect to red wires from R and DFT using wire nuts.
KIT NO.
315776-701
315776-702
315776-703
315776-704
315776-705
6. Route wires from crankcase heater into control box and
connect to contactor push-on terminals L1 and T1.
7. Connect wires to compressor; yellow wire from run capacitor
to R terminal, blue wire from run capacitor to S terminal, and
black wire from T1 terminal on contactor to C terminal. Install
compressor terminal box cover.
8. Connect thermostat wires to compressor section defrost board.
(See Fig. 4.)
Make sure control compartment access panel is closed before
restoring power to unit. Failure to follow this warning could
cause personal injury or death resulting from electrical shock
or moving parts.
9. Route line power wires into control box from the unit
disconnect box. Connect 1 wire to yellow wire from L2 on
contactor and connect the other wire to black wire from L1 on
contactor using wire nuts.
2. Route outdoor fan motor wires into control box. Connect 1
wire to the blue wire from OF2 terminal on the defrost control
board. Connect the remaining wire to the orange wire from L2
on contactor using wire nuts.
10. Install access wrapper and top cover.
3. Route orange wire from LPS into control box and connect to
Y push-on terminal. Connect yellow wire from T1 terminal on
cycle protector board to other LPS terminal.
NOTE: Control wiring applies to total electric systems. For 38SQ
fossil fuel systems, discard old furnace interface kit and install new
Optimizer II® or current interface control. Refer to Installation
Instructions for control wiring.
11. Turn on power to unit and cycle unit several times to assure
correct operation.
4. Route wires from reversing valve solenoid into control box
and connect to push-on terminals O and C on defrost control
board.
2
WARNING: CONTAINS R-22 VAPOR
CHARGE RELIEVE PRESSURE AT SCHRADER
VALVE BEFORE REMOVING BRACKET.
38HQ500402
THIS CONTROL BOX ASSEMBLY
HAS BEEN MODIFIED TO THE
38SQ100 SERIES. FOR CONTROLS
REPLACEMENT PARTS REFERENCE
THE 38SQ1-- PARTS REPLACEMENT
GUIDE.
P/N 315780-201 REV A
A89279
A94138
Fig. 2—Control Box Prior to Modification
Fig. 3—Modified Control Box
3
THERMOSTAT
SUBBASE
HH93AZ183 OR
HH93AZ186
INDOOR UNIT
38SQ
ELECTRIC HEATER
COMPRESSOR
TERMINAL
SECTION DEFROST
BOARD
BOARD
R
R
R
C
C
C
Y
Y
Y
G
G
O
O
P
W3
E
E
W2
W2
O
*
*
W2
X
†
L
L
† JUMPER WIRE
REQUIRED FOR
SUPPLEMENTAL
HEAT L.E.D.
38SQ
OUTDOOR COIL
CONTROL BOX
38SQ
COMPRESSOR
SECTION
CIRCUIT BOARD
DFT
JUMPER
* REMOVE
WIRE(S) WITH
APPLICATION OF
OUTDOOR THERMOSTAT(S)
R
DFT
COOLING AND 2-STAGE HEATING
WITH ELECTRIC HEAT
AFTER MODIFICATION
A92323
Fig. 4—Modified Wiring
Copyright 1994 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
43022c
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101
Catalog No. 563-782
Printed in U.S.A.
Form 38SQ-19SI
Pg 4
6-94
Replaces: 38SQ-18SI
Tab 5a 5a
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