Carrier 50BYN006 Dimensions and installation guide

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 535-050 Printed in U.S.A. Form 50BY-1SI Pg 1 1-02 Replaces: New
Book 1 4
Ta b 2 b 7 a
Installation, Start-Up and
Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . 1
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Step 1 — Complete Pre-Installation Checks . . . . . . 1
Step 2 — Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . 2
Splitting a 50BYN024. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Unit Discharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Vibration Isolation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Step 3 — Install Accessories . . . . . . . . . . . . . . . . . . . . . 2
Step 4 — Install Ductwork . . . . . . . . . . . . . . . . . . . . . . . . 7
Step 5 — Install Rain/Condensate Drain Line. . . . 11
Step 6 — Complete Electrical Connections. . . . . . 13
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-20
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Compressor Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Operating Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20, 21
Cleaning Evaporator and Condenser Coils . . . . . . 20
Lubrication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Condenser Fan Adjustment . . . . . . . . . . . . . . . . . . . . . 20
Pulley Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Belt Tension Adjustment . . . . . . . . . . . . . . . . . . . . . . . . 20
Changing Fan Wheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Fan Bearing Replacement . . . . . . . . . . . . . . . . . . . . . . . 20
Concentric Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21, 22
Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Inspection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Air Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Condensate Drain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Checking System Charge . . . . . . . . . . . . . . . . . . . . . . . 21
Access Panel Removal . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Evaporator-Fan Motor Removal . . . . . . . . . . . . . . . . . 22
Pressure Relief Device . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Cycle-LOC™ Protection Device . . . . . . . . . . . . . . . . . 22
Time Guard® II Control. . . . . . . . . . . . . . . . . . . . . . . . . . 22
High and Low Pressurestats . . . . . . . . . . . . . . . . . . . . 22
Oil Charge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . 23-25
START-UP CHECKLIST . . . . . . . . . . . . . . . . . . CL-1, CL-2
SAFETY CONSIDERATIONS
Installing, starting up, and servicing air-conditioning com-
ponents and equipment can be dangerous. Only trained, quali-
fied installers and service mechanics should install, start-up,
and service this equipment.
When working on the equipment, observe precautions in the
literature and on tags, stickers, and labels attached to the equip-
ment. Follow all safety codes. Wear safety glasses and work
gloves.
GENERAL
ECOZONE indoor package units are designed to provide
the flexibility required in replacement, renovation, and new
construction. Units are available in 6 sizes from 5 tons to
20 tons. Belt-drive condensers provide adequate static to over-
come ducting and louver static losses. This allows units to be
positioned against an existing window or wall louver, or ducted
to the outside as required.
Convenient rear connections allow easy access for outside
air connections and air side economizer. Unit supply air
discharge may be vertical or horizontal front. These packaged
vertical packaged units are fully piped and wired. Units are
complete with a belt drive evaporator section and built-in
ducted air-cooled condenser. Airflow is horizontal or vertical.
All units are designed to fit through most standard doors.
The 20 ton size may be easily field split to simplify moving the
units into existing buildings. See Fig. 1-3 for unit dimensions
and refer to Table 1 for unit operating weights.
INSTALLATION
ECOZONE 50BY units are intended for indoor installation
only. Determine building alterations required to run piping,
wiring and ductwork. Follow dimensional drawings for duct-
work, piping locations, electrical wiring (refer to Table 2 for
electrical data) and overall unit dimensions.
Read all installation instructions before installing the unit.
Step 1 — Complete Pre-Installation Checks —
Examine unit for damage incurred during shipment. File claim
immediately with transit company if damage is found. Check
the shipment for completeness. Verify that the nameplate elec-
trical requirements match the available power supply.
DO NOT place the unit in a horizontal position that would
allow oil to drain into the top of the compressor. Do not allow
refrigerant lines to come into contact with wiring or sharp ob-
jects or edges. Do not lift or move unit by putting pressure on
refrigerant lines.
Before performing service or maintenance operations on
unit, turn off main power switch to unit. Electrical shock
could cause personal injury.
Use care in handling, rigging, and setting bulky equipment.
50BYN006-024
ECOZONE Vertical Single Package
Air-Cooled Units
5 to 20 Tons

2
Step 2 — Rig and Place Unit — Units are mounted
on skids. Leave the unit on the skid until it is in the final posi-
tion. While on the skid, the unit can be rolled, dragged or fork-
lifted; do not apply force to the unit. Use a minimum of 3 roll-
ers when rolling, and raise from above to remove the skid when
unit is in the final position. See Fig. 4 for rigging details.
PLACING THE UNIT — The selected unit location should
not be adjacent to an acoustically sensitive space. The best lo-
cations for these units are mechanical rooms, near elevator
shafts, near restrooms, near stairwells or other similar loca-
tions. Position the unit where large supply of outdoor air is
available for the unit inlet. Be sure to leave enough space for
the return air inlet access to the evaporator and condenser coils
for cleaning and maintenance. Units located on the same floor
should have a minimum of 6 ft of clearance between condenser
air openings. Units located floor-to-floor should have a mini-
mum of 10 ft between units to prevent recirculation of condi-
tioned air. DO NOT locate units where they will recirculate
conditioned air. This will cause increased head pressure which
can cause units to trip on high pressure. See Fig. 1-3 for recom-
mended unit clearances and locations.
Either provide inlet filters to protect the coils, or locate the
unit in an area free from airborne dirt or other foreign material
which could clog the coils.
The units are designed to pass through most 36-in. door
openings. The filter rack and duct mounting flanges may also
be removed for additional clearance.
Splitting a 50BYN024 — The size 024 unit height
exceeds 80 in. and may not clear all door openings. It may be
necessary to split the unit in order to move it into the desired
installation location. Refer to the following instructions to split
the unit:
NOTE: This unit and its 2 sections are heavy. Three people
are required to move the sections safely. You will also need
safety goggles, gloves and a dolly.
1. Move the unit to a work area close to the final installation
location.
2. Be certain the service valves for all 3 circuits are in the
“OFF” position. See Fig. 5. If any valves have been
opened, the system must be evacuated.
3. Undo the suction line at the threaded fitting between the
upper and lower sections of the unit. See Fig. 6.
4. Mark and undo each of the liquid lines for all 3 circuits at
the threaded connections to the expansion valve and the
connection to the filter drier. See Fig. 6.
5. Carefully move the liquid lines to the side, keeping them
inside the unit.
6. You can now separate the upper and lower sections of
the unit. Remove the 8 bolts that hold the two sections
together. See Fig. 7. Once the bolts are removed, save the
nuts, bolts and washers for use in re-assembly.
7. Carefully lift the fan/coil section from the base section
and separate.
8. Move the separate sections to the installation location.
9. Place the bottom section first and then place the top sec-
tion on top of it.
10. Bolt the sections together.
11. Reconnect the suction lines with the threaded fittings.
12. Reconnect the liquid lines to the expansion valve and
filter drier. DO NOT mix circuits; be certain each line is
returned to its original location.
13. Connect a vacuum pump to the service port by the com-
pressor, on the suction line.
14. Pull a vacuum to 30 microns.
15. Pull the unit down and check to make sure all joints are
tight and leak free. Open the discharge line service valve.
See Fig. 6.
16. Open the liquid line service valve. See Fig. 6.
17. Follow the unit's start-up instructions.
NOTE: Accessory items need to be installed before the
ducts are attached.
Unit Discharge — Units are shipped from the factory
configured for vertical discharge. The units (except the
50BYN014) can be converted to front or horizontal discharge
by following these instructions:
1. Remove the screws (8) from the top front access panel to
gain access to the fan section.
2. Loosen the supply fan mounting bolts (4) and slide the
fan motor back until the belts (3) are loose.
3. Remove the belts (3).
4. Remove the screws (8) from the unit top panel that holds
the fan.
5. Remove the top cover and fan.
6. Position fan where the top front access panel was mounted.
7. Secure the fan with the screws removed in Step 1.
8. Re-mount the belts.
NOTE: Some units require different belts for different fan
set ups. If this is the case, new belts are provided inside the
fan enclosure.
9. Slide the fan motor back until the proper belt tension is
obtained. Secure the motor with the mounting bolts (4).
10. Mount front access cover on top of the unit (where the top
cover was originally) and secure with the screws (8) re-
moved in Step 4.
Vibration Isolation — Unit compressors are internally
isolated and the compressor compartment is lined with acousti-
cal insulation. If additional vibration isolation is desired, rubber
pads may be located under each unit corner or unit may be
mounted on rubber shear isolators. Spring isolators are not nor-
mally required. Ductwork attached to the unit should be isolated
from the unit with a flexible collar on the inlet and outlet ducts.
Step 3 — Install Accessories (If Required) —
Refer to the following and the instructions provided with the
individual accessory. Refer to Fig. 8 for typical system set up.
HEATING COILS — Accessory steam or hot water heating
coils are mounted in the unit return air before the cooling coil.
1. Remove the filter rack provided with the unit.
2. Mount the filter rack on the coil.
3. Mount the coil in the position where the filter rack was.
NOTE: The filter rack may be used with either ducted or
free air return set ups. Make sure adequate air mixing occurs
to prevent coil freeze-up. A 50BB900---001 freeze protec-
tion thermostat is recommended.
LOW AMBIENT KIT — If the unit will be operated with
inlet air to the condenser below 50 F, a head pressure control
low-ambient damper may be required. The low-ambient kit
controls head pressure by discharge dampers on the condenser
fan. The dampers are actuated by a refrigerant-operated piston
connected to the discharge line of the condenser. If a low-
ambient accessory will be used, install it at this time (before
final ductwork connections are made).
INLET FILTER KIT — An accessory filter rack may also be
installed on the air inlet to help keep the coil clean. This filter
rack should be installed before the ductwork is attached to the
unit (if required in your specific application).
Refer to installation instructions provided with the accesso-
ries for installation details.

3
Fig. 1 — Base Unit Dimensions — 50BYN006-014
DIMENSIONAL CHART
CORNER WEIGHTS
50BY 006 008 012 014
DIM mm ft-in. mm ft-in. mm ft-in. mm ft-in.
A1800 5-105/81800 5-105/81780 5-10 1780 5-10
B1040 3- 5 1231 4- 01/21613 5- 31/21804 5-11
C690 2- 31/8690 2- 31/8745 2- 53/8745 2- 53/8 D765 2- 61/8765 2- 61/8825 2- 81/2825 2- 81/2
E355 1- 2 420 1- 41/2608 2- 0 675 2- 25/8
F170 0- 63/4158 0- 61/4191 0- 71/2193 0- 75/8
G320 1- 05/8357 1- 2 402 1- 37/8452 1- 53/4
H310 1- 01/4350 1- 13/4372 1- 25/8424 1- 43/4
J593 1-113/8593 1-113/8665 2- 21/4665 2- 21/4
K554 1- 97/8554 1- 97/8457 1- 6 457 1- 6
L584 1-11 584 1-11 584 1-11 584 1-11
M23 0- 07/823 0- 07/823 0- 07/823 0- 07/8
N17 0- 05/817 0- 05/817 0- 05/817 0- 05/8
P11.5 0- 01/211.5 0- 01/211.5 0- 01/211.5 0- 01/2
Q43 0- 13/443 0- 13/443 0- 13/443 0- 13/4
R605 1-113/4605 1-113/4605 1-113/4605 1-113/4
S50 0- 2 55 0- 21/855 0- 21/855 0- 21/8
T360 1- 21/8400 1- 33/4357 1- 2 357 1- 2
V50 0- 2 20 0- 07/824 0- 1 24 0- 1
W660 2- 2 660 2- 2 660 2- 2 660 2- 2
X535 1- 91/8535 1- 91/8590 1-111/4590 1-111/4
Y190 0- 71/2190 0- 71/2190 0- 71/2190 0- 71/2
Z124 0- 47/8124 0- 47/8124 0- 47/8124 0- 47/8
AA 475 1- 63/4475 1- 63/4475 1- 63/4475 1- 63/4 AB 140 0- 51/2140 0- 51/2140 0- 51/2140 0- 51/2
AC 60 0- 23/860 0- 23/860 0- 23/860 0- 23/8
AD 21 0- 07/821 0- 07/821 0- 07/821 0- 07/8
AE 225 0- 87/8225 0- 87/8217 0- 81/2217 0- 81/2
AF 155 0- 61/8155 0- 61/8155 0- 61/8155 0- 61/8
AG 190 0- 71/2190 0- 71/2190 0- 71/2190 0- 71/2 AH 73 0- 27/861 0- 23/859 0- 23/859 0- 23/8
AJ 895 2-111/41110 3- 93/41495 4-107/81686 5- 63/8
AK 386 1- 31/4405 1- 4 260 0-105/8356 1- 2
AL 433 1- 5 480 1- 67/8433 1- 5 433 1- 5
AM ————275
0-107/8275 0-107/8
AN ————4331-5 4331-5
AP 80 0- 31/880 0- 31/880 0- 31/880 0- 31/8
AQ 880 2-105/81070 3- 61/81455 4- 91/41645 5- 43/4
AR 41 0- 15/841 0- 15/841 0- 15/841 0- 15/8
AS 533 1- 9 605 1-117/8807 2- 73/4920 3- 01/4
AT 347 1- 15/8355 1- 2 375 1- 23/4395 1- 31/2
AV 50 0- 2 50 0- 2 50 0- 2 50 0- 2
AW 231 0- 91/8231 0- 91/8169 0- 61/2169 0- 61/2
CORNER WEIGHTS
50BY 006 008 012 014
CORNER kg lbkglbkglbkglb
A65.3 144 84 185 107 236 108 238 B68.5 151 81 179 107 236 113 248 C69.4 153 89 136 108 239 127 280 D65.8 145 92 203 108 239 119 263
NOTES: 1. Dimensions in [ ] are in millimeters. 2. Center of gravity. 3. Direction of airflow. 4. One side of unit must have minimum of 3′[914] clearance for filter
removal.

4
Fig. 2 — Base Unit Dimensions — 50BYN016
DIMENSIONAL CHART
DIM UNIT 50BY016
mm ft-in.
A1980 6- 6 B1905 6- 3 C745 2- 53/8
D825 2- 81/2
E543 1- 93/8
F257 0-101/8
G356 1- 2
H353 1- 17/8
J665 2- 21/4
K635 2- 1
L597 1-111/2
M19 0- 03/4
N17 0- 05/8
P17 0- 05/8
Q43 0- 13/4
R607 1-117/8
S84 0- 33/8
T402 1- 37/8
V22 0- 07/8
W765 2- 61/8
X603 1-113/4 Y190 0- 71/2
Z124 0- 47/8
AA 432 1- 5 AB 83 0- 31/4
AC 60 0- 23/8
AD 21 0- 07/8
AE 217 0- 81/2
AF 141 0- 51/2
AG 190 0- 71/2 AH 86 0- 33/8
AJ 1737 5- 83/8
AK 318 1- 01/2
AL 483 1- 7
AM 311 1- 01/4
AN 483 1- 7
AP 70 0- 23/4
AQ 1765 5- 91/2 AR 41 0- 15/8
AS 979 3- 21/2
AT 385 1- 31/8
AV 276 0-107/8
AW 169 0- 61/2
AX 50 0- 2
CORNER WEIGHTS
UNIT 50BY016
kg lb
A119 263 B142 312 C152 334 D128 281
NOTES: 1. Dimensions in [ ] are in millimeters. 2. Center of gravity. 3. Direction of airflow. 4. One side of unit must have minimum of 3′[914] clearance for filter
removal.

5
Fig. 3 — Base Unit Dimensions — 50BYN024
CORNER WEIGHTS
CORNER 50BYN024
kg lb
A183 403 B194 428 C192 424 D181 400
DIMENSIONAL CHART
DIM 50BYN024
mm ft-in.
A2341 7- 81/4
B2108 6-11 C794 2- 71/4 D872 2-103/8
E581 1-107/8
F184 0- 71/4
G406 1- 4
H379 1- 3
J830 2- 85/8
K796 2- 71/4
L584 1-11
M28 0- 11/8
N40 0- 15/8
P51 0- 2
Q43 0- 13/4
R805 2- 73/4
S65 0- 21/2
T457 1- 6
V16 0- 05/8
W921 3- 01/4
X610 2- 0 Y202 0- 8
Z86 0- 33/8
AA 422 1- 45/8 AB 140 0- 51/2
AC 60 0- 23/8
AD 21 0- 07/8
AE 226 0- 87/8
AF 184 0- 71/4
AG 220 0- 83/4 AH 62 0- 21/2
AJ 1984 6- 61/8
AK 345 1- 15/8
AL 530 1- 87/8
AM 356 1- 2
AN 530 1- 87/8
AP 76 0- 3
AQ 1956 6- 5 AR 41 0- 15/8
AS 1085 3- 63/4
AT 399 1- 33/4
AV 314 1- 03/8
AW 236 0- 91/4
AX 50 0- 2
AY 1471 4-10
NOTES: 1. Dimensions in [ ] are in millimeters. 2. Center of gravity. 3. Direction of airflow. 4. One side of unit must have minimum of 3′[914] clearance for filter
removal.

6
Table 1 — Physical Data
LEGEND
*The 20 ton unit is factory wired for 2 stages of capacity control. With the addition of a
3-stage thermostat or outdoor-air thermostat, the unit is capable of 3 stages of capacity
control.
†Shaft center distances shown are for vertical discharge arrangement.
**Shaft center distances shown are for horizontal discharge arrangement.
UNIT 50BYN 006 008 012 014 016 024
NOMINAL CAPACITY (tons) 57
1/210 12 15 20
UNIT OPERATING WEIGHT (lb) 594 765 948 1036 1190 1654
COMPRESSOR Carrier Scroll
Model SR58 SR75 SR58 SR58/SR75 SR75 SR75
Quantity 1121/12 3
Rpm 3500
Oil Charge (oz) 44 50 44/44 50/44 50/50 50/50/50
Steps of Control 1122 2 2*
OPERATING CHARGE R-22 (lb) 8.6 10.1 8.0/8.8 8.8/10.6 9.9/9.9 9.9/9.9/9.9
EVAPORATOR FAN Adjustable, Belt-Driven, Centrifugal
Nominal Cfm 2000 3000 4000 4800 6000 8000
Cfm Range 1,500-2,500 2,250-3,750 3,000-5,000 3,750-6,250 4,500-7,500 6,000-10,000
Available Static 1.2 1.25 2.25 2.25 2.0 2.0
Fan Size 101/2x 71/211 x 8 121/2x 91/214 x 12 121/2x 91/2121/2x 91/2
Number of Fans 1111 2 2
Standard Speed Range (Rpm) 1058-1449 950-1300 860-1120 849-1117 1045-1308 930-1160
Max Allowable Rpm 1900 1700 1500 1360 1900 1600
Motor Rpm 1725
Vertical Belt Quantity...Type 1...A33 1...A34 1...B41 1...B45 2...A42 2...B52
Horizontal Belt Quantity — Type 1...A24 1...A24 1...B39 None 2...A32 2...B40
Fan Pulley (in.) 41/443/485/885/865/871/2
Motor Pulley (in.) 21/2-31/221/2-31/241/8-51/241/8-51/24-5 4-5
Nominal Hp...Frame Size 11/2...145T 2...145T 3...182T 5...184T 5...184T 71/2...184T
Fan Shaft Size (mm) 20 20 20 20 25 25
Motor Shaft Size (in.) 7/87/811/811/811/811/8
Center Distance (in.) min/max† 13.6-13.8 13.2-13.4 10.4-11.9 9.6-10.6 12.2-13.7 17.6-18.7
Center Distance (in.) min/max.** 6.6-7.7 6.4-7.4 N/A N/A 7-8 10.6-11.4
EVAPORATOR COIL 3/8-in. OD, Enhanced Copper Tube, Aluminum Fins
Quantity Rows...Fin/in. 3...14 4...14 4...14 4...14 4...14 4...15
Face Area (sq ft) 5.7 7.0 9.5 10.8 12.2 17.6
RETURN AIR FILTERS 1 or 2 in. Disposable Type
Quantity...Size 1...16 x 25 1...25 x 25 3...20 x 25 3...16 x 25 2...25 x 25 8...16 x 20
1...20 x 25 1...20 x 25 1...20 x 25 1...20 x 25
CONDENSER FAN Adjustable, Belt-Driven, Centrifugal
Nominal Cfm 3000 4500 6000 7200 9000 12,000
Cfm Range 2,250-3,750 3,375-5,625 4,500-7,500 5,400-9,000 6,750-11,250 9,000-15,000
Available Static 1.0 1.0 1.0 1.0 1.0 1.0
Fan Size 11 x 11 121/2x 121/211 x 11 11 x 11 121/2x 121/214 x 14
Number of Fans 1122 2 2
Standard Speed Range (Rpm) 952-1304 849-1117 1038-1305 1038-1305 903-1136 930-1150
Max Allowable Rpm 1700 1500 1700 1700 1500 1360
Motor Rpm 1725
Belt Quantity...Type 1...A65 1...B68 2...A67 2...A67 2...A78 2...B85
Fan Pulley (in.) 58
1/263/463/473/473/4
Motor Pulley (in.) 21/2-31/241/2-51/24-5 4-5 4-5 4-5
Nominal Hp...Frame Size 2...145T 3...182T 5...184T 5...184T 5...184T 71/2...184T
Fan Shaft Size (mm) 20 20 25 25 25 25
Motor Shaft Size (in.) 7/811/811/811/811/811/8
Center Distance (in.) min/max 26.7-27.4 23.1-24.2 24.7-26.2 25.0-26.2 28.9-30.5 34.5-35.9
CONDENSER COIL 3/8-in. OD, Enhanced Copper Tube, Aluminum Fins
Quantity Rows...Fins/in. 4...14 4...14 5...14 5...14 5...14 5...15
Face Area (sq ft) 6.4 7.7 10.5 11.8 14.2 19.4
CONTROLS 24 Volts Provided in Unit
High Pressure Cutout (psig) 395
Cut-in (psig) 300
Low Pressure Cutout (psig) 27
Cut-in (psig) 67
Fusible Plug 203 F
Time Guard® II Devices 5 Minutes on Each Circuit
CONDENSATE DRAIN LINE 2 @ 3/4BPS
NPT — National Pipe Thread
BPS — British Pipe Standard
(NPT pipe will work with the type of fitting)

7
Step 4 — Install Ductwork — The 50BYN unit is de-
signed for use either with or without ductwork or rain louvers.
If either is used, care must be taken to eliminate air recircula-
tion. Recirculation can be minimized by discharging through
an extension elbow. When properly designed, single deflection
discharge louvers can be applied to ductwork and to the unit air
discharge. Fixed rain louvers over discharge outlets can cause
excessive recirculation and nuisance high-pressure switch cut-
outs. Obstructions closer than 10 ft to the discharge air pattern
can also cause significant recirculation.
NOTE: See Fig. 9 for recommended duct sizing
The 50BYN016 and 024 units are shipped with the con-
denser flanges stored inside the condenser section. Before
attaching ductwork, mount the flanges to the condenser as
shown in Fig. 10.
CONDENSER AIR DUCT — The condenser supply and dis-
charge air duct should be as short and straight as possible. The
cross section area of the duct should never be less than the face
area of the unit openings. Ductwork should be insulated to pre-
vent moisture condensation on the unit panels during cold
weather. (See Fig. 11.)
Insulate as follows:
1. If metal ductwork is used, insulation may be applied
on the inside of the duct. This installation should be ex-
tended to cover the inside of the duct flanges. It is neces-
sary to insulate the inside of the ducts at the duct flanges
to reduce heat loss from the metal cabinet by conduction
through the duct flanges and into the cold duct. Interior
insulation allows the metal duct to approach room tem-
perature. It also prevents condensation from forming and
collecting under the insulation which will occur with
exterior duct insulation.
NOTE: Fiberglass duct board may also be used if permitted
by local codes.
2. If insulation is applied to the outside of the metal duct, the
inside must be insulated for a length of 10 in. from the
unit (including the duct flanges) or up to the flexible duct
vapor barrier on the outside, which must be tightly sealed
to prevent condensation under the insulation.
SPREADER BAR
SUPPORTS
UNDER SKID
Fig. 4 — 50BYN Unit Rigging
SERVICE
VALVE
Fig. 5 — 50BYN024 Unit (Service Panels Removed)

8
THREADED LIQUID LINE
FITTING ON TXV
(3 CIRCUITS)
THREADED
SUCTION CONNECTION
(3 CIRCUITS)
LIQUID LINE
THREADED
CONNECTIONS
AND SERVICE
VALVES
(3 CIRCUITS) SUCTION LINE
SERVICE PORT
DISCHARGE LINE
SERVICE VALVE
DISCHARGE LINE
SERVICE PORT
UNITS SPLIT
AT THIS POINT
Fig. 6 — 50BYN024 Front View
Fig. 7 — Splitting the 50BYN024 Unit

9
FILTER DRIER
SERVICE
VALVE
LIQUID LINE
THREADED
CONNECTION
COMP
SERVICE
VALVE
THREADED
CONNECTION
SERVICE
PORT
DISCHARGE LINE
SERVICE
PORT
THREADED
CONNECTION
TXV
SUCTION LINE
COND
EVAP
Fig. 8 — Typical System Setup

10
*
INLET
LOUVER
F
B
D
C
4 3/4" 1"
50BYN
A
DISCHARGE
LOUVER
50BYN
G
45°
5 5/8"
4"
4"
14 GAGE ALUMINUM OR
18 GAGE GALVANIZED STEEL
FLANGE
NOT PERMISSIBLE
BLADE STIFFENER
FOR LOUVER WIDTHS
OVER 30"
5"
3" 1/2"
4"
1"
30°
EXHAUST
VANE DEFLECTOR
CONDENSER INTAKE
Fig. 9 — Typical Recommended Condenser Duct Dimensions
*Access panel for condenser coil cleaning.
INLET LOUVER DETAIL DISCHARGE LOUVER DETAIL
DEFLECTOR DETAIL
DIMENSIONS (in.)
UNIT
50BYN A BCD F G
006 24 141/8620
1/826 345/8
008 24 153/4621
3/426 411/8
012 24 14 6 20 26 571/4
014 24 14 6 20 26 643/4
016 30 157/8621
7/8301/8691/2
024 30 18 6 24 361/478

11
CONDENSER AIRFLOW LOUVERS — The proximity of
the condenser air inlet and discharge airstreams makes the pos-
sibility of air recirculation quite high. It is possible to use one
louver to route inlet and discharge airstreams but it is not
recommended.
Separate inlet and discharge louvers are recommended (see
Fig. 9) to avoid air leakage from discharge to inlet. A baffle
may also be used on the outside of the building to direct dis-
charge away from the air inlet.
Louvers should be selected with sufficiently strong blades
for the application. Louver blades should be at least 30-in. wide
and constructed of a minimum of 18-gage metal.
EVAPORATOR DUCTWORK — Supply duct should be
properly supported and the aspect ratio as close to square as
possible. Duct should be sized for a maximum of 2000 feet per
minute velocity in areas outside the equipment room. The duct
should be lined with acoustical insulation for a minimum of
10 ft beyond the equipment room. A flexible duct connection
should be used on the connection to the unit to prevent trans-
mission of any unit vibrations into the duct.
Return duct may be attached to the unit, but is not necessary.
The return to the unit should prevent line of sight visibility to
the space. Insulated return duct is also recommended for acous-
tically sensitive spaces. Maximum velocity should not exceed
1000 ft per minute over occupied spaces. Adequate return area
is essential for proper operation.
Step 5 — Install Rain/Condensate Drain Line
The 50BYN unit has a drain connection for evaporator
condensate and a connection on the unit base to drain any rain
water that may accumulate. Rain drain connection can be made
on either side of the unit. Block whichever drain is not being
used, but DO NOT BLOCK BOTH drain locations.When con-
necting rain drains and condensate drains from the unit to floor
drains, sinks, or hoppers, connect drains downstream of trap to
ensure that condensate does not drain back into the unit.
A drain kit is provided (shipped in the fan section). This
kit consists of PVC drain fittings to adapt to field-supplied
threaded pipe. Make connections through the unit side panel.
Some applications may require connection to either galvanized
steel or copper drain pipe; consult local code requirements for
details.
Pitch drain pipe downward at a slope of at least 1/4-in. per ft
for proper drainage. Provide tees plugged on one side for
cleanouts. Leave clearance for servicing, and observe all local
sanitary codes.
The condensate trap should have a depth adequate to allow
3-in. of water in the trap (see Fig. 12) with the unit running.
IMPORTANT: A rain drain connection MUST BE
USED if any possibility exists of rain water entering
the unit.
IMPORTANT: NEVER use pipe smaller than 3/4inches
in the drain run.
DUCT FLANGE
Fig. 10 — Placement of Duct Flanges (50BY016,024)

12
*Provide access for cleaning condenser coil.
Fig. 11 — 50BYN Applications

13
Step 6 — Complete Electrical Connections
GENERAL — Verify that nameplate electrical requirements
match available power supply. Voltage at condenser must be
within the minimum and maximum shown in Table 2 and phas-
es must be balanced within 2%. Contact local power company
for line voltage corrections. Never operate a motor where a
phase imbalance in supply voltage is greater than 2%.
Use the following formula to determine the percentage of
voltage imbalance:
UNBALANCED 3-PHASE SUPPLY VOLTAGE — Use
the following formula to determine the percent of voltage
imbalance.
Percent Voltage Imbalance
Example: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
Determine maximum deviation from average voltage:
(AB) 457 – 452 = 5 v
(BC) 464 – 457 = 7 v
(AC) 457 – 455 = 2 v
Maximum deviation is 7 v.
Determine percent of voltage imbalance:
% Voltage Imbalance = 100 x
= 1.53%
This amount of phase imbalance is satisfactory as it is be-
low the maximum allowable 2%.
Unit operation on improper line voltage or excessive phase
imbalance may be considered abuse and any resulting damage
may not be covered by Carrier warranty.
All wiring must be in accordance with local or NEC
(National Electrical Code) regulations.
POWER WIRING — The units must have adequate overcur-
rent protection, fuses, or HACR (Heating, Air Conditioning
and Refrigeration) breakers, according to the national and ap-
plicable local codes.
For field power connections, all main power wiring enters
the unit through a factory-punched access hole under the con-
trol box. Attach power wires to the power connections on the
main power terminal block in the unit control box. Be sure to
install a ground wire.
CONTROL WIRING — All units require an accessory ther-
mostat package to complete the unit control system. Any of the
following controls systems can be used:
1. Room-mounted thermostat. Thermostat may be mounted
in an appropriate location in the conditioned space. Route
the wires from the thermostat to the low voltage connec-
tion of the control box. Connect wires to the low voltage
terminal block. The fan switch on the thermostat will con-
trol fan operations.
2. Carrier TEMP thermostat. Mount relay pack for the
Carrier TEMP thermostat in the low voltage section of the
control box. Wire from the relay pack to the low voltage
terminal strip and from the relay pack to the thermostat.
FREEZE PROTECTION THERMOSTAT — An accessory
freeze protection thermostat is required when a liquid line loss-
of-charge switch is installed or when the unit is equipped with
an airside economizer for intermediate or cold weather opera-
tion. Refer to Fig. 13 and 14 and the installation instructions
included with the thermostat. Field installation of an evaporator
freeze-up thermostat (50BB900001) is required.
WINTER START MODIFICATIONS — When starting air-
cooled units under low-ambient temperature conditions, the
compressor may pull suction pressure down below the low-
pressure cutout switch setting causing the compressor to shut off.
At extremely low temperatures, the low-pressure switch may
open during the off cycle, preventing the compressor from start-
ing. In these cases, winter start control is required as follows:
If 50BZ unit has a low-pressure switch, the use of the winter-
start kit (part no. CRWINSTR01A00) is recommended. This kit
bypasses the low-pressure switch on start-up.
START-UP
General — Complete the start up checklist on page CL-1
before attempting system start-up.
1. Set indoor thermostat system switch to OFF position
and fan switch to AUTO position.
2. Check all electrical connections, fuses, starter and pres-
sure control resets.
3. Check operation of evaporator fan motor and ensure fan
rotation is correct. If rotation needs to be reversed, dis-
connect main power and switch any 2 leads on the load
side of the disconnect switch.
4. Adjust fan speed. Units are belt-driven condenser units
and allow for a wide range of inlet static and condenser
airflow requirements. It may be necessary to adjust the
condenser airflow to account for these inlet conditions.
Inadequate airflow will result in poor unit performance
and possible nuisance tripping of high-pressure switches.
If an airflow is not specified, use the nominal airflow
from Tables 3 and 4 and adjust the fan speed to compen-
sate for actual job conditions. Use Table 1 to determine
proper fan speed. If the unit trips on high pressure due to
high condensing temperature it may be necessary to in-
crease the fan speed and condenser airflow.
5. The outdoor-air fans cycle with the compressor Be sure
fans are running during compressor rotation.
= 100 x max voltage deviation from average voltage
average voltage
Average Voltage = 452 + 464 + 455
3
= 1371
3
= 457
IMPORTANT: If supply voltage phase imbalance is
more than 2%, contact your local electric utility com-
pany immediately.
7
457
To prevent injury, ensure that ducting or wire fan guards
are installed on the condenser fan before starting the unit.
TO UNIT
DRAIN
PLUG
MINIMUM PITCH
ONE IN. PER
10 FT. OF LINE OPEN
VENT
SEE
NOTE
Fig. 12 — External Trap Condensate Drain
NOTE: Trap should be deep enough to offset maximum unit static
difference. A 4-in. trap is recommended.

14
Table 2 — Electrical Data
LEGEND
*Minimum Ckt Amps and MOCP Amps values per NEC (see Note 1).
†The overcurrent protective device for the unit shall be fuse or HACR circuit breaker (see Note 1).
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equipment
(NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuse
or HACR circuit breaker. Canadian units may be fuse or circuit breaker.
2. Wire sizing amps are a sum of 125% of the compressor RLA plus 100% of indoor fan
motor FLA.
3. Motors are protected against primary single phasing condition.
4. Indoor-fan motors are 3-phase motors of same voltage as unit.
UNIT
50BYN V-P H-H z
VOLTAGE
RANGE
COMPRESSOR
NO. 1
COMPRESSOR
NO. 2
COMPRESSOR
NO. 3
CONDENSER
FAN
INDOOR-FAN
MOTOR
POWER
SUPPLY*
Min Max RLA LRA RLA LRA RLA FLA Hp FLA Hp FLA MCA MOCP†
006
208/230-3-60 187 253 18.3 125 ————2.0 7.5 1.5 6.6 37.0 50
460-3-60 414 506 9.2 67 ————2.0 3.4 1.5 3.0 17.8 25
575-3-60 518 632 7.3 27 ————2.0 2.7 1.5 2.4 14.3 20
008
208/230-3-60 187 253 20.4 146 ————3.0 10.6 2.0 7.5 43.6 60
460-3-60 414 506 10.2 73 ————3.0 4.8 2.0 3.4 21.0 30
575-3-60 518 632 8.2 50 ————3.0 3.9 2.0 2.7 16.8 20
012
208/230-3-60 187 253 17.7 125 17.7 125 ——5.0 16.7 3.0 10.6 67.1 80
460-3-60 414 506 8.9 67 8.9 67 ——5.0 7.6 3.0 4.8 32.3 40
575-3-60 518 632 7.1 27 7.1 27 ——5.0 6.1 3.0 3.9 25.9 30
014
208/230-3-60 187 253 17.7 125 20.9 146 ——5.0 16.7 5.0 16.7 76.4 90
460-3-60 414 506 8.9 67 10.5 73 ——5.0 7.6 5.0 7.6 36.7 45
575-3-60 518 632 7.1 27 8.4 50 ——5.0 6.1 5.0 6.1 29.4 35
016
208/230-3-60 187 253 20.9 146 20.9 146 ——5.0 16.7 5.0 16.7 80.4 100
460-3-60 414 506 10.5 73 10.5 73 ——5.0 7.6 5.0 7.6 38.7 45
575-3-60 518 632 8.4 50 8.4 50 ——5.0 6.1 5.0 6.1 31.0 35
024
208/230-3-60 187 253 20.9 146 20.9 146 20.1 146 7.5 24.2 7.5 24.2 116.8 125
460-3-60 414 506 10.5 73 9.9 73 9.5 73 7.5 11.0 7.5 11.0 56.0 60
575-3-60 518 632 8.4 50 8.4 50 8.4 50 7.5 9.0 7.5 9.0 45.2 50
FLA — Full Load Amps
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
MOCP — Maximum Overcurrent Protective
Device (see Note 1)
NEC — National Electrical Code
RLA — Rated Load Amps

15
W1
Y1
G
W3
CK1
CK2
R
C
W2
Y2
RS2
RS+5
RS1
RS GND
UNIT
GROUND
33CS250-01
R
G
T1
Y1
X
C
Y2
TB2
T2
50BYN
(012 SIZE UNIT AND LARGER)
WIRE NUT
SHIELD (CUT AND
TAPE BACK)
REMOTE
ROOM
SENSOR
(P/N ZONECCORRS01)
O/W2
Y1
R
G
Y/Y2
W/W1
C
B
L
DO NOT USE
S1
S2
33CSPTN-01
R
G
T1
Y1
X
C
Y2
TB2
T2
50BYN
(012 SIZE UNIT AND LARGER)
WIRE NUT
SHIELD (CUT AND
TAPE BACK)
REMOTE
ROOM
SENSOR
(P/N ZONECCORRS01)
UNIT
GROUND
NOTE: Remote sensor is field-installed option.
Fig. 13 — Thermostat Connection Diagram with 33CS250-01 Thermostat
NOTE: Remote sensor is field-installed option.
Fig. 14 — Thermostat Connection Diagram with 33CSPTN-01 Thermostat

16
Table 3 — Condenser Fan Performance
LEGEND
Shaded areas require field-supplied drive.
50BYN
STATIC PRESSURE (in. wg)
Cfm 0.0 0.2 0.4 0.6 0.8 1.0
Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp Rpm Bhp
006
2,000 566 0.18 710 0.30 846 0.40 972 0.46 1070 0.61 1130 0.72
2,500 753 0.40 880 0.59 927 0.63 1020 0.79 1105 1.10 1184 1.35
3,000 940 0.83 985 0.90 1080 1.00 1122 1.10 1200 1.29 1320 1.46
3,500 1047 1.20 1140 1.47 1173 1.50 1250 1.70 1292 1.40 1360 1.59
4,000 1250 1.94 1257 2.00 1333 2.10 1390 2.41 1410 2.60 1470 2.76
008
3,000 547 0.30 670 0.54 751 0.60 840 0.80 920 1.10 995 1.50
3,750 760 0.89 824 1.10 920 1.25 964 1.30 1040 1.53 1110 2.10
4,500 910 1.53 940 1.70 1020 1.90 1090 2.08 1173 2.40 1240 2.59
5,250 1020 2.00 1095 2.40 1170 2.90 1180 3.00 1240 3.10 1300 3.53
6,000 1180 3.10 1195 3.20 1260 3.70 1320 4.16 1380 4.80 1440 5.60
012
4,000 665 0.40 803 0.65 920 0.97 989 1.20 1080 1.48 1163 1.90
5,000 830 0.82 912 1.20 1010 1.55 1088 1.70 1170 2.00 1246 2.50
6,000 976 1.70 1070 2.16 1131 2.30 1210 2.66 1318 2.90 1390 3.36
7,000 1120 2.85 1198 3.00 1273 3.20 1343 3.70 1410 4.21 1474 4.90
8,000 1282 3.90 1353 4.50 1420 5.06 1517 5.30 1580 5.93 1640 6.70
014
4,800 703 0.62 840 1.05 860 1.10 950 1.29 1090 1.62 1172 2.02
6,000 853 1.12 902 1.60 1060 2.10 1130 2.30 1210 2.66 1290 3.20
7,200 1045 2.40 1140 3.00 1191 3.20 1270 3.62 1290 3.79 1357 4.60
8,400 1190 3.60 1270 4.20 1340 4.89 1421 5.10 1490 5.85 1560 6.70
9,600 1380 5.70 1452 6.50 1520 7.13 1550 7.20 1611 7.50 1670 8.23
016
6,000 600 0.60 720 1.02 820 1.51 910 2.10 950 2.20 1025 2.80
7,500 736 1.50 833 1.86 920 2.50 1015 2.80 1040 3.08 1106 3.80
9,000 942 3.20 1030 3.60 1040 4.20 1110 4.50 1141 4.80 1230 5.03
10,500 1075 5.10 1150 6.25 1220 6.80 1280 6.72 1340 7.50 1400 8.50
12,000 1230 7.10 1310 8.20 1350 8.96 1410 9.20 1465 9.80 1470 10.10
024
8,000 560 1.68 640 2.04 705 2.40 770 3.00 850 3.60 920 3.98
10,000 710 3.36 760 3.72 820 4.20 870 4.80 930 5.40 975 6.00
12,000 845 5.28 890 5.70 945 6.20 975 6.71 1025 7.26 1090 7.70
14,000 960 8.14 1020 8.80 1076 9.24 1090 9.90 1125 10.50 1150 11.00
16,000 1090 11.60 1150 12.50 1190 12.80 1200 13.20 1230 13.70 1250 14.00
Bhp — Brake Horsepower

17
Table 4 — Evaporator Fan Performance
LEGEND
1. Shaded areas require field-supplied drive.
2. Italics require field-supplied motor.
CFM EXTERNAL STATIC PRESSURE (in. wg)
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2
50BYN006
1500 Rpm 690 860 978 1100 1210 1310 1400
Bhp 0.20 0.30 0.35 0.47 0.44 0.56 0.69
1750 Rpm 800 950 1080 1140 1240 1340 1430
Bhp 0.22 0.36 0.53 0.60 0.68 0.90 1.10
2000 Rpm 953 1090 1140 1240 1340 1430 1520
Bhp 0.44 0.61 0.65 0.80 0.86 1.04 1.23
2250 Rpm 1040 1160 1270 1340 1430 1480 1550
Bhp 0.58 0.80 0.97 1.10 1.23 1.30 1.33
2500 Rpm 1209 1324 1430 1460 1550 1640 1720
Bhp 0.84 1.10 0.38 1.40 1.56 1.85 2.13
50BYN008
2250 Rpm 683 827 950 980 1100 1130 1180
Bhp 0.24 0.43 0.66 0.73 0.76 0.83 0.94
2625 Rpm 845 980 990 1100 1150 1220 1320
Bhp 0.57 0.83 0.88 1.03 1.18 1.23 1.32
3000 Rpm 930 1046 1150 1210 1270 1340 1500
Bhp 0.71 1.01 1.34 1.37 1.59 1.64 1.94
3375 Rpm 1060 1172 1270 1350 1380 1400 1505
Bhp 1.07 1.42 1.81 1.91 2.04 2.13 2.29
3750 Rpm 1250 1350 1370 1390 1440 1520 1550
Bhp 1.72 2.10 2.27 2.37 2.63 2.70 2.89
50BYN012
3000 Rpm 710 790 870 930 980 1060 1100 1180 1240 1290 1390 1400
Bhp 0.66 0.77 0.91 0.97 1.14 1.23 1.38 1.44 1.67 1.88 2.04 1.99
3500 Rpm 720 820 920 920 1050 1120 1190 1240 1280 1320 1400 1410
Bhp 0.70 0.86 1.21 1.40 1.65 1.69 1.98 1.98 2.17 2.33 2.50 2.45
4000 Rpm 852 960 1050 1090 1180 1200 1240 1320 1330 1440 1410 1420
Bhp 0.95 1.35 1.80 2.02 2.28 2.40 2.30 2.60 2.70 2.80 2.90 2.96
4500 Rpm 946 1042 1130 1210 1220 1320 1330 1340 1420 1430 1500 1550
Bhp 1.32 1.76 2.25 2.76 2.83 3.10 3.20 3.34 3.45 3.53 4.07 4.49
5000 Rpm 1040 1125 1205 1280 1320 1340 1430 1470 1500 1520 1580 1610
Bhp 1.75 2.22 2.73 3.21 3.40 3.75 3.97 4.41 4.68 4.87 4.76 5.03
Bhp — Brake Horsepower

18
Table 4 — Evaporator Fan Performance (cont)
LEGEND
1. Shaded areas require field-supplied drive.
2. Italics require field-supplied motor.
CFM EXTERNAL STATIC PRESSURE (in. wg)
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2
50BYN014
3,600 Rpm 580 640 710 780 845 910 975 1040 1080 1130 1180 1280
Bhp 0.67 0.80 0.94 1.06 1.25 1.49 1.63 1.76 1.97 2.30 2.50 2.70
4,200 Rpm 670 730 760 900 915 935 1040 1050 1100 1150 1215 1285
Bhp 1.03 1.18 1.40 1.63 1.72 1.83 2.13 2.20 2.34 2.70 2.80 3.30
4,800 Rpm 760 840 850 930 940 1035 1060 1090 1130 1205 1280 1330
Bhp 1.50 1.79 1.86 2.12 2.15 2.48 2.67 2.80 2.95 3.30 3.70 3.80
5,400 Rpm 850 880 955 1005 1050 1060 1115 1160 1205 1270 1340 1360
Bhp 2.10 2.40 2.64 2.87 3.05 3.14 3.40 3.70 3.92 4.35 4.56 4.76
6,000 Rpm 955 980 1035 1060 1110 1150 1170 1220 1240 1285 1360 1380
Bhp 2.98 3.22 3.35 3.60 3.80 4.00 4.22 4.40 4.60 4.75 5.60 5.80
50BYN016
4,500 Rpm 676 840 970 940 1037 1092 1170 1251 1320 1370 1432 1462
Bhp 0.60 1.04 1.35 1.50 1.60 1.72 1.80 1.85 1.90 2.54 2.90 3.20
5,250 Rpm 731 865 980 1083 1100 1180 1210 1280 1370 1434 1490 1550
Bhp 0.80 1.20 1.65 2.00 2.20 2.35 2.47 2.70 2.98 3.42 3.50 3.67
6,000 Rpm 891 1020 1134 1140 1217 1240 1313 1327 1400 1450 1514 1580
Bhp 1.44 2.16 2.80 2.90 3.00 3.18 3.40 3.50 3.70 4.25 4.50 4.80
6,750 Rpm 950 1060 1160 1240 1280 1350 1390 1450 1514 1540 1590 1640
Bhp 1.80 2.50 3.18 3.70 3.80 4.10 4.30 4.70 5.10 5.30 5.90 6.30
7,500 Rpm 1060 1160 1290 1330 1350 1420 1488 1540 1600 1650 1707 1760
Bhp 2.50 3.27 4.37 4.50 4.70 5.02 5.40 5.68 6.20 6.50 6.90 7.40
50BYN024
6,000 Rpm 670 786 890 915 990 1090 1120 1180 1270 1310 1360 1470
Bhp 0.85 1.32 1.92 2.10 2.31 2.64 2.86 3.30 3.49 4.00 4.30 4.60
7,000 Rpm 820 930 980 1035 1070 1140 1225 1270 1290 1330 1380 1480
Bhp 1.75 2.46 2.60 3.01 3.40 3.52 4.00 4.30 4.50 4.80 5.30 5.66
8,000 Rpm 980 1033 1080 1150 1170 1250 1290 1310 1365 1410 1460 1522
Bhp 3.30 3.50 3.65 4.13 4.35 5.00 5.20 5.35 5.90 6.30 6.64 7.20
9,000 Rpm 1105 1120 1200 1240 1300 1330 1385 1430 1460 1510 1590 1620
Bhp 4.80 4.90 5.20 5.40 6.20 6.40 7.00 7.20 7.50 8.30 9.26 10.40
10,000 Rpm 1230 1250 1320 1326 1390 1415 1460 1515 1530 1580 1625
Bhp 6.00 6.80 7.03 6.80 7.80 8.20 8.46 9.45 9.70 10.50 10.90
Bhp — Brake Horsepower

19
Compressor Rotation — To determine whether or not
compressor is rotating in the proper direction:
1. Connect service gages to suction and discharge pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge pres-
sure should rise, as is normal on any start-up.
4. If the suction pressure does not drop and the discharge
pressure does not rise to normal levels.
5. Note that the evaporator fan is probably also rotating in
the wrong direction.
6. Turn off power to the unit and tag disconnect.
7. Reverse any two of the unit power leads.
8. Reapply power to the unit.
9. The suction and discharge pressure levels should now
move to their normal start-up levels.
NOTE: When the compressor is rotating in the wrong direc-
tion, the unit makes an elevated level of noise and does not
provide cooling.
Operating Sequence — All units require the addition
of a thermostat accessory package to complete the control cir-
cuit. The sequence of operation may vary depending on which
package is selected.
ROOM-MOUNTED THERMOSTAT — These units use an
electronic, communicating electronic, or mechanical thermo-
stat mounted in the conditioned space.
FAN CIRCULATION — When the fan selector switch is set
to the ON position, the indoor-fan motor is energized through
G on the thermostat and the indoor-fan contactor is energized.
This starts the indoor fan motor (IFM). The fan will operate to
provide continuous air circulation.
COOLING — The indoor fan will operate continuously or
when the compressor runs, depending on the setting of the ther-
mostat fan selector switch. When the thermostat closes (on a
call for cooling Y1 on the thermostat), the control relay (CR),
outdoor-fan contactor (OFC) and compressor contactor(s) (C1
and C2 on 20 ton) close. The control relay will start the indoor
fan if it is not already running. The outdoor-fan contactor will
start the condenser fan and the compressor contactors will im-
mediately start the first stage compressor(s). The 50BYN024
unit as wired from the factory has two compressors on first
stage and one on second stage. This may be altered (see appli-
cation data section of the product data catalog).
A second stage on 50BYN012-024 units will close if addi-
tional cooling demand is required, and will then start the
second-stage compressor. When the thermostat is satisfied, the
second stage compressor will stop first, and then the first stage
compressors will stop when cooling demand is satisfied. The
outdoor fan will also stop as soon as the first stage cooling is
satisfied.
HEATING — The indoor fan will operate continuously or
when the heater runs, depending on the setting of the thermo-
stat fan selector switch. When the thermostat closes (on a call
for heating), the thermostat activates the water or steam control
valve or electric heater to meet heating requirements.
CARRIER TEMP THERMOSTAT — The Carrier TEMP
System is a control system which includes a relay pack, TEMP
system thermostat, sensors and appropriate wiring. The TEMP
thermostat is the system controller and works much like a room
thermostat, but provides for communicating control. The
TEMP thermostat requires the addition of an accessory
relay pack to interface with the unit. This relay pack may be
mounted in the low-voltage control compartment. The system
operation is the same as stated in the Room-Mounted Thermo-
stat section above.
CARRIER VARIABLE VOLUME AND TEMPERATURE
(VVT)® SYSTEM — The VVT system is a control system
that includes a relay pack (which may be mounted in the low
voltage control compartment); monitor thermostat; zone con-
trollers modulating supply duct dampers; modulating bypass
controller sensors; and appropriate wiring. The VVT thermo-
stat is the system controller. It sends messages to the relay pack
which then sends the appropriate signals to the 50BYN unit for
fan, heating and cooling. The monitor thermostat also gathers
information from the zone controllers, which control the zone
supply dampers. It provides a zoned, all-air system for both
heating and cooling which supplies variable volume, variable
temperature air to the zones conditioned.
ALL UNITS — The control circuit incorporates a current-
sensing lockout relay (Cycle-LOC™ device) that locks off the
compressor(s) when any safety device is activated (low or high
pressure switches, outdoor-fan motor overload, or compressor
internal overload). If any compressor safety device opens, the
compressor(s) will stop and a 24-v signal will be sent to the X
connection of the low-voltage terminal strip. The signal may be
used to light an indicator light on the thermostat to show that
service is required on the unit. Since the unit is protected by the
Cycle-LOC device, the compressor(s) will not restart following
a safety interruption unless the thermostat is satisfied without
cooling operation. To reset the Cycle-LOC control device,
manually turn the control power to the OFF, then back to the
ON position. High- and low-pressure switches and motor over-
load protectors will reset automatically when the condition
which caused the device to trip has dropped below the reset
condition. A 5-minute timer (Time-Delay Relay [TDR]) will
prevent the compressor(s) from restarting for 5 minutes after
any compressor has stopped.
If the condenser-fan motor overheats due to motor over-
load or lack of cooling air, the internal fan protector will open
the circuit internally in the motor, and the fan will stop. If a
safety control in the unit opens, the condenser fan will also
stop.
ACCESSORIES — Low ambient control on 50BYN units is
accomplished with a refrigerant operated damper located on
the condenser fan discharge. Low ambient operation does not
affect operating sequence.
WINTERSTART — Since these units are equipped with a
27 psig low-pressure switch, a 3-minute low-pressure switch
bypass is recommended for operation below 50 F. Order Win-
ter Start Control accessory no. CRWINSTR01A00 and install
according to the instructions supplied with the kit.
DEFROST THERMOSTAT (50BB-900- - -001) — This ther-
mostat is installed on the evaporator coil and is recommended
with Winter Start control. Install thermostat according to in-
structions supplied with the kit.
ECONOMIZER — When the thermostat turns the indoor fan
on, the economizer relay is energized and the actuator is
powered on. The actuator moves the dampers to the minimum
position as determined by the adjustment potentiometer on
the actuator. If the system uses a CO2sensor, the minimum
position is determined by the potentiometer on the required
field-supplied adapter. On a call for heating from the thermo-
stat (W1 and/or W2 energized), the economizer remains at the
minimum position.
NOTE: If a CO2sensor is used, the economizer can modu-
late based on the carbon dioxide level in the space. There is
no low leaving-air temperature limit control. Controls to
accomplish this must be field-supplied and installed.

20
On a call for cooling from the thermostat (Y1 energized),
the actuator logic module determines if the outdoor air en-
thalpy is acceptable according to the set point on the actuator. If
the outdoor air enthalpy is acceptable, the economizer begins to
modulate open and is controlled to maintain a 56 F leaving air
temperature. If outdoor air enthalpy is unacceptable, the logic
module bypasses the use of outdoor air and energizes Y1 of the
unit. On a call for a second stage of cooling (Y2 energized), the
actuator energizes Y1 on the unit if the outdoor air enthalpy is
acceptable. If the outdoor air is unacceptable, the actuator logic
module energizes Y2 of the unit. When the system is equipped
with a CO2sensor in a modulating configuration, the following
applies: If the system is operating in the Cooling mode and the
demand for fresh air to reduce the carbon dioxide level in the
space is greater than the cooling load demand, the actuator
modulates to reduce the carbon dioxide level and does not
modulate towards closed if the leaving-air temperature is
below 56 F. If, however, the cooling demand is greater than the
demand to reduce the carbon dioxide level, the actuator modu-
lates open and controls to a 56 F leaving-air temperature.
The damper modulates open when the leaving-air tempera-
ture demand is greater than the airflow demand required for the
CO2sensor to reduce carbon dioxide levels. When the CO2
sensor is installed, there is no minimum leaving air temperature
control at the economizer.
USING A CO2SENSOR WITH THE ECONOMIZER —
A separately ordered carbon dioxide sensor can be used to sig-
nal the economizer to open the outdoor-air dampers to admit
fresh air and dilute the indoor CO2level. Sensor descriptions
and part numbers are shown below.
The CO2sensors listed above are all factory set for a range
of 0 to 2000 ppm and a linear voltage output of 2 to 10 vdc.
The relay normally open dry contacts (TB-3 and TB-4) are fac-
tory set to close at 1000 ppm. Refer to the installation instruc-
tions with the CO2sensor for electrical ratings of contacts and
information on connecting to power supply. Switch contacts
can be used to set off an alarm or light to indicate CO2levels
higher than the switch set point. Any changes to the factory
configuration require the purchase of the User Interface
Program (UIP) or Sensor Calibration Service Kit, which also
contains the UIP. For correct modulation of the economizer
actuator motor, a separately ordered adapter (Honeywell
part no. Q769C1007) is required.
SERVICE
Cleaning Evaporator and Condenser Coils — Do
not use high-pressure water or air. Damage to fins may result.
Clean coils with a vacuum cleaner, fresh water, compressed air,
or a bristle brush (not wire). Backflush coil to remove debris.
Commercial coil cleaners may also be used to help remove
grease and dirt. Steam cleaning is NOT recommended.
Units installed in corrosive environments should be cleaned
as part of a planned maintenance schedule. In this type of appli-
cation, all accumulations of dirt should be cleaned off the coil.
Take care not to get water in the system ducts or unit
insulation.
Lubrication — Fan motors have permanently lubricated
bearings.
Condenser Fan Adjustment — To prevent personal
injury, be sure wire fan guards are secured in place over each
fan discharge (or that fans are ducted) before starting the unit.
TO CHANGE FAN SPEED
1. Shut off unit power supply.
2. Loosen fan belt by loosening fan motor from mounting
bracket. Do not loosen fan motor mounting bracket from
unit.
3. Loosen movable pulley flange setscrew (Fig. 15).
4. Screw movable flange toward fixed flange to increase fan
speed and away from fixed flange to decrease speed. In-
creasing fan speed increases load on motor. Do not ex-
ceed maximum allowable fan speed or motor full load
amps indicated on motor nameplate and in Table 2.
5. Set movable flange setscrew at nearest flat of pulley hub
and tighten setscrew.
6. Check pulley alignment and belt tension adjustment as
described below.
7. Check fan operation. Repeat above procedure as required.
Pulley Alignment — Shut off unit power supply. Loosen
fan motor pulley setscrews and slide fan pulley along fan shaft.
Make angular alignment by loosening motor from mounting
bracket (see Fig. 15). Check alignment with a straightedge.
Belt Tension Adjustment — Shut off unit power sup-
ply. Loosen fan motor mounting plate bolts. Do not loosen
motor mounting bracket from unit. Move fan motor mounting
plate until proper belt tension is achieved (approximately 1/2-in.
deflection with 8-lb tension at midpoint of belt span).
Changing Fan Wheel — If a fan wheel should fail, it
may be replaced as follows:
1. Remove belts from fan pulley.
2. Loosen locking collars on the fan bearings and set screws
on the fan wheels.
3. Remove the shaft through the access panel on either side
of the unit.
4. Remove the fan cut-off plate in the fan discharge.
5. Remove the fan wheel through the fan discharge opening.
6. Replace the wheel, and reverse Steps 1-4 above.
Fan Bearing Replacement — If a fan bearing fails,
replace it as follows:
1. Remove belts from the fan pulley.
2. Support fan shaft.
3. Loosen locking collar on fan bearing.
4. Remove bearing from the shaft.
5. Install new bearing onto the shaft, and reverse Steps 1-3
above.
Concentric Alignment — Shaft and wheels must be
concentrically centered with the venturi or air inlet of the fan
housing (see Fig. 16).
Shaft bearings are supports by bearing supports (Fig. 17). If
shaft and wheels are concentrically misaligned from shipping
shock, it is possible to rebend the bearing support arms to the
original positions. Replace the bearing support if it has exten-
sive damage.
CO2SENSOR ACCESSORIES
Part Numbers Description
CGCDXSEN001A00 Wall Mount Sensor
(No Display)
CGCDXSEN002A00 Wall Mount Sensor
With Display
CGCDXSEN003A00 Duct Mount Sensor
(No Display)
CGCDXGAS001A00 Sensor Calibration
Service Kit
CGCDXPRM001A00 User Interface Program
(UIP)