Carrier 48PG Series Dimensions and installation guide

48PG03-07
Single Package Rooftop Units
Electric Cooling/Gas Heating
with PURON® (R-410A) Refrigerant
and Electromechanical Controls
Installation, Start-Up, and
Service Instructions
CONTENTS
Page
SAFETY CONSIDERATIONS ....................... 1,2
INSTALLATION ................................... 2-19
Step 1-- Plan for Unit Location ..................... 2
Step 2 -- Provide Unit Support ...................... 2
• ROOF CURB
• ALTERNATE UNIT SUPPORT
Step 3 -- Rig and Place Unit ......................... 2
• INSTALLATION ONTO CURB
• SLAB MOUNT (Horizontal Units Only)
Step 4 -- Field Fabricate Ductwork .................. 4
Step 5 -- Make Unit Duct Connections .............. 4
Step 6 -- Install Flue Hood and Inlet Hood ........... 7
Step 7 -- Install External Trap
for Condensate Drain .............................. 8
Step 8 -- Install Gas Piping .......................... 9
Step 9 -- Make Electrical Connections .............. 9
•FIELD POWER SUPPLY
• FIELD CONTROL WIRING
Step 10 -- Optional EconoMi$er IV ................. 13
Step 11 -- Install All Accessories ................... 19
PR E-START-U P..................................... 20
START-UP ....................................... 20-36
SERVICE ........................................ 37-45
Cleaning ............................................ 37
Lubrication ......................................... 38
Evaporator Fan Service and Replacement .......... 39
Evaporator Fan Performance Adjustment ........... 39
Evaporator Fan Belt Tension Adjustment ........... 39
Condenser-Fan Adjustment ........................ 39
Verify Sensor Performance ......................... 40
Economizer Operation During Power Failure ....... 40
Evacuation ......................................... 40
Refrigerant Charge ................................. 40
Gas Valve Adjustment .............................. 42
High Altitude ....................................... 42
LP (Liquid Propane) Gas Use ....................... 42
Main Burners ....................................... 42
Filter Drier .......................................... 43
Protective Devices .................................. 43
Relief Devices ...................................... 43
Control Circuit 24-V ................................ 43
Replacement Parts ................................. 43
Diagnostic LEDs .................................... 43
TROU BLESHOOTING ............................ 46-49
Unit Troubleshooting ............................... 46
EconoMi$er IV Troubleshooting .................... 48
Phase Loss Protection ............................. 49
UNIT START-UP CHECKLIST ..................... CL-I
SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning equipment can
be hazardous due to system pressure and electtic_d components.
Only trained and qu_dified service personnel should inst_dl,
repair, or service air-conditioning equipment.
Untrained personnel can perform the basic maintenance
functions of cleaning coils and filters and replacing filters. All
other operations should be performed by trained service per-
sonnel. When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached to the unit,
and other safety precautions that may apply.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for unbrazing operations. Have
fire extinguishers available for _dl brazing operations.
Before performing service or maintenance operations on
unit, turn off main power switch to unit. Electrical shock
could cause personal injury.
Puron (R-410A) refrigerant systems operate at higher pres-
sures than stan&trd R-22 systems. Do not use R-22 service
equipment or components on Puron refrigerant equipment.
If service equipment is not rated for Puron refrigerant,
equipment dmnage or personal injury may result.
1. [mproper inst_dlation, adjustment, alteration, service,
or maintenance can cause property &Lmage, personal
injury, or loss of life. Refer to the User's Information
Manual provided with this unit for mote details.
2. Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any other
appliance.
What to do if you smell gas:
1. DO NOT try to light any appliance.
2. DO NOT touch any electrical switch, or use any
phone in your building.
3. IMMEDIATELY call your gas supplier from a neigh-
bor's phone. Follow the gas supplier's instructions.
4. If you cannot reach your gas supplier, c_dl the fire
department.
Disconnect gas piping flom unit when pressure testing at
pressure greater than 0.5 psig. Pressures greater than
0.5 psig will cause gas valve damage resulting in haztudous
condition. [f gas valve is subjected to pressure greater than
0.5 psig, it must be replaced before use. When pressure
testing field-supplied gas piping at pressures of 0.5 psig or
less, a unit connected to such piping must be isolated by
closing the manual gas valve(s).
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111 Catalog No. 534-80209 Printed in U.S,A, Form 48PG-8SI Pg 1 8-05 Replaces: New

IMPORTANT: Units have high ambient operating limits. If [
limits are exceeded, the units will automatically lock the I
compressor out of operation. Manual reset will be required
to restart the compressor:
INSTALLATION
Step 1 -- Plan for Unit Location -- Select a loca-
tion for the unit and its support system (curb or other) that
provides minimum clearances required for safety, unit perfor-
mance and service access below, around and above unit as
specified in unit drawings. Consider also the effect of adjacent
units.
Do not install unit in an indoor location. Do not locate ;dr
inlets near exhaust vents or other sources of contaminated air.
For proper unit operation, adequate combustion and ventilation
air must be provided in accordance with Section 5.3 (Air for
Combustion and Ventilation) of the National Fuel Gas Code,
ANSI Z223A (American Natiomd Stan&u_ds Institute). Al-
though unit is weatherproof, guard against water from higher
level runoff and overhangs.
I_cate mechanical &_afl system flue assembly at least 4 ft
fi_om any opening through which combustion products could
enter the building, and at least 4 fl fi_)m any adjacent building
(or per local code). Locate the flue assembly at least 10 fl (or
per local code) from an adjacent unit's fi_eshair intake hood if
within 3 ft of stone elevation. When unit is located adjacent to
public w;dkways, flue assembly must be at least 7 fl above
grade.
Select a unit mounting system that provides adequate height
to allow installation of condensate trap per requirements. Refer
to Step 7 -- Install External Trap for Condensate Drain for re-
quired trap dimensions.
ROOF MOUNT -- Check building codes for weight distribu-
tion requirements. Unit operating weight is shown in Table 1.
Step 2 -- Provide Unit Support
ROOF CURB -- Asselnble or install accessory roof curb in
accordance with instructions shipped with this accessory. See
Fig. 1. Install insulation, cant strips, roofing, and counter flash-
ing as shown. DuctwoN can be inst_dled to roof curb before unit
is set in place. DuctwoN must be attached to curb and not to the
unit. Curb must be level. This is necessary to permit unit drain to
limction properly. Unit leveling tolerance is _+J/l_ in. per linem
1l in any direction. Refer to Accessory Roof Curb Installation
Instructions for additional information as required. When acces-
sory roof curb is used, unit may be installed on class A, B, or C
roof covering material. C_urier roof curb accessories are for flat
roofs or slab mounting.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a watertight seal. Install gasket with the roof
curb as shown in Fig. 1. Improperly applied gasket can also
result in air leaks and poor unit performance. Do not slide
unit to position on roof curb.
ALTERNATE UNIT SUPPORT- When a curb cannot be
used, inst_dl unit on a noncombustible surface. Support unit
with sleepers, using unit curb support area. If sleepers cannot
be used, support long sides of unit with a minimum of 3 equal-
ly spaced 4-in. x 4-in. pads on each side.
Step 3 -- Rig and Place Unit -- Inspectunit for trans-
portationdmnage. See Table 1 for physical &_ta. File any claim
with transportation agency.
All panels must be in place when rigging. Damage to unit
may result.
Do not di'op unit; keep upright. Use spreader baLs over unit
to prevent sling or cable damage. Rollers may be used to move
unit across a roof. Level by using unit rail as a refelence; level-
ing tolerance is _+ 1/16 in. per linear ft in any direction. See
Fig. 2 for additional information. Unit rigging weight is shown
in Fig. 2.
Rigging holes are provided in the unit base rails as shown in
Fig. 2. Refer to rigging instructions on unit.
INSTALLATION ONTO CURB -- The 48PG units gue de-
signed to fit on the accessory full perimeter curb. Correct
placement of the unit onto the curb is critical to operating per-
formance. To aid in correct positioning, place unit on roof curb
to maintain l/4-in, gap between the inside of rail and roof curb
on long sides and a l/2-in, gap between the inside of rail grad
roof curb on both duct and condenser ends. Refer to Fig. 1 and
3, to assure proper duct opening alignment.
NOTE: Before positioning unit onto curb, refer to Step 7 --
Install External Trap for Condensate Drain on page 8 for
cle_uances.
Do not slide unit to position it when it is sitting on the curb.
Curb gasketing material may be &imaged and leaks may
result.
SLAB MOUNT (Horizontal Units Only) -- Provide a level
concrete slab that extends a minimum of 6-in. beyond unit cab-
inet. Install a grovel apron in front of condenser-coil air inlet to
prevent gross and foliage from obstructing airflow.
NOTE: Horizont_d units may be inst_flled on a roof curb if
required.

SU?PL7 AIR
OPENING
o_'
[151 0]
_op N NG FOR
ELECiR[CAL
SERV_C
'1
1.
SEE DETAIL D \ SEE OEiAII E_\
\ \
REAR
GASKET
o 7M0: [111_
RIGID INSULAI[ON <
(F[ELD SUPPLEEb)
NAIL
COUNTER FLASHING
(FIELD SUPPLIED)
ROOFING FELT
(FIELD SUPPLIED)
CA_r STRIP
I_IELD SUPPI[{D)
ROO_]NG MAi_iAL
(_[ELD SUPPLIEDI
TYPICAL 4 S]OES
3131132 ':
[964 3]_
i O2 3/8 ¸=
Fig. 1 -- Roof Curb Details
UNH SIZE CONNECTOR
i 48PG i "C= ACCESSO_
, , PACKAGE
i.... i......L.......
[6 4] --) --
[>E]A[L D
SCA_E 11:37
112
DETAIL
SCALE I]:32
NOTES:
ROOFCUR_ ACCESSORYIS S_IPPEO UNASSEM_LED
INS_LAT[_ PANELS¸
_I_ENSIONS IN I ]_RE iN _[LLi_ETERS
ROOFC_R_ _ALVANIZE_ 81_EL
ATTACH _UCi_OR_ TO ¢UR_ _EL_G_S ON _UCT
SE_ViCE CLEARANC_ 4 H O_ E_C_ SIDE
GAS SERV;CE ?LAIE IS _ARi OF A SEPARATELY
SHIPP_ ACCESSORYPACKAGE
GAS SERVICE ?LAI_ CAN _E USED WiT_ EIiHER
ACCESSOR7ROOFCURB
_OL7 HEA_S I0 BE ON INSIDE OP ELANGE
CIEARA_CE ]S II_] 0 0-_I_" TY? ALl CORNERS
i DIRECT[ON OF A]RFLO_
__P[_ING FOR
SEE NOTE 9_
SERVICE
TE
NOTE 7 &8
SEE NOTE 2

Hook rigging shackles through holes in base rail, as shown in
Detail A. Holes in base rails are centered around the unit
center of gravity. Use wooden top skid, when rigging, to
_revent rigging straps from damaging unit.
Fig. 2 -- 48PG Rigging Label
Step 4 -- Field Fabricate Ductwork-- On vel_ical
units, secure all ducts to roof crab and building structure. Do not
connect dm_'ork to unit. For horizontal applications, field-
supplied flanges should be attached to horizontal dischtuge
openings and all ductwork secmed to the flanges. Insulate and
weatherproof all external ductwork, joints, and roof openings
with counter flashing and mastic in accor&mce with applicable
codes.
Ducts passing through an unconditioned space must be
insulated and covered with a vapor bturiel:
If a plenum return is used on a vertical unit, the return
should be ducted through the roof deck to comply with applica-
ble fire codes.
A minimum clearance is not required around ductwork.
Cabinet return-air static pressure (a negative condition) shall
not exceed 0.35 in. wg with economizer or 0.45 in. wg without
economizel:
These units are designed for a minimum continuous return-
air temperature in heating of 50 F (dry bulb), or an intermittent
operation down to 45 F (diy bulb), such as when used with a
night set-back thermostat.
To operate at lower return-air temperatures, a field-supplied
outdoor-air temperature control must be used to initiate both
stages of heat when the temperature is below 45 E Indoor com-
fort may be compromised when these lower air temperatures
are used with insufficient heating temperature rise.
Step 5 -- Make Unit Duct Connections
VERTICAL SUPPLY/RETURN CONFIGURATION -- Unit
is shipped in vertical supply/return configuration. Ductwork
openings are shown in Fig. 1and 3. Attach the ductwork to the
roof curb. Do not attach duct directly to the unit.
For venic_d supply and return units, tools or pans could
&op into ductwork and cause an injmy. Install a 90-degree
turn in the return ductwork between the unit and the condi-
tioned space. If a 90-degree elbow cannot be installed, then
a grille of sufficient strength and density should be installed
to prevent objects from falling into the conditioned space.
HORIZONTAL SUPPLY/RETURN APPLICATIONS -- Unit
can be field-converted from vertical supply/return to horizontal
supply/return. Remove all screws securing horizontal duct
covers to duct panel. Save panels. Install duct covers in the
vertical duct openings in the basepan with the insulation side
up. Covel.s will drop into openings and can be secured using
field-supplied self-tapping screws. Ductwork can be attached
to duct flanges provided on unit. When securing ductwork to
unit, do not drill in area below bead or above top edge of duct
opening.

BASE UNIT 48PC
NOMINAL CAPACITY (Tons)
OPERATING WEIGHT (]b)
Unit*
Economizer
Vertical
Horizontal
Roof Curb
14-in.
24-in.
COMPRESSOR
Quantity
Oil Type
Number of Refrigerant Circuits
Oil (oz)
REFRIGERANT TYPE
Expansion Device
Operating Charge (Ib)
CONDENSER COIL
Condenser A (Outer)
Rows-.Fins/in.
Face Area (sq ft)
Condenser B (inner)
Rows-.Fins/in.
Face Area (sq ft)
CONDENSER FAN
Quantity.- Diameter (in.)
Nominal Cfm (Total, all fans)
Motor Np
Nominal Rpm -- High Speed
Nominal Rpm -- Low Speed
EVAPORATOR COIL
Rows...Finslin.
Face Area (sq ft)
EVAPORATOR FAN
Quantity._ Size (in.)
Type Drive
Nominal Cfm
Maximum Continuous Bhp
Motor Nominal Rpm
Motor Frame Size
Fan Rpm Range
Motor Bearing Type
Maximum Fan Rpm
Motor Pulley Pitch Diameter Range (in.)
Fan Pulley Pitch Diameter (in.)
Nominal Motor Shaft Diameter (in.)
Belt...Pitch Length (in.)
BelL.Type
Pulley Center Line Distance Min. (in.)
Pulley Center Line Distance Max. (in.)
Speed Change per Full Turn of
Movable Pulley Flange (rpm)
Movable Pulley Maximum Full
Turns from Closed Position
Factory Pulley Betting (rpm)
Fan Shaft Diameter at Pulley (in.)
GAS HEAT SECTION
Rollout Switch
Open Temperature (F)
Closed Temperature (F)
Standard Units
Gas Input (Btuh) Stage l/Stage 2
Low NOx Units
Burner Orifice Diameter (in....drill size)**
Natural Gas
Liquid Propane
Thermostat Heat Anticipator Setting (amps)
First Stage
Second Stage
Manifold Pressure (in. wg)
Natural Gas
Liquid Propane
Gas Valve Quantity
Gas Supply Pressure Range (in. wg)
Field Gas Connection Size (in.)
HIGH-PRESSURE SWITCH (psig)
Cutout
Reset (Auto.)
LOW-PRESSURE SWITCH (psig)
Cutout
Reset IAuto.)
FREEZE PROTECTION THERMOSTAT (F)
Cutout
Reset (Auto.)
RETURN-AIR FILTERS
Quantit_L..Size lin.l
LEGEND
TXV -- Thermostatic Expansion Valve
_Aiuminum evaporator coil/aluminum condenser coil
tSingle phase/three phase.
_For applications less than 2000 ft elevation.
Low
High
Low
High
Low
High
Low
High
Low
High
Low
High
Low
High
Low
High
Low
High
Low
High
LOW
High
Low
High
Low
High
Low
High
Low
High
Low
Med
High
Low
Med
High
PGDtL
PGEtM
PGF/N
PGDtL
PGEtM
PGF/N
Table 1 -- Physical Data
03 04 07
2 3 6
774 786 961
40 40 40
50 50 50
122 122 122
164 184 164
1I I 1
1 I I 138 56
T×V I I TXV7.3 19.0
1...17 I2...17
12.6 12.6
-- 2...17
-- 12.6
1...24 I 1...24
3500 [ 4500
1/8 1/4
825 1100
300 300
2...1598I I 4...159.8
1...12x 9
1...12x 9
Belt
Belt
8OO
0.85
0.85
1620
48Y
48Y
482-736
656-1001
Ball
2000
1.9-2.9
1.9-2.9
6.8
5.0
1/2
49.3
49.3
AX
AX
16.2
16.2
20.2
20.2
48
65
5
5
736
794
3/4
N/A
N/A
195
N/A
N/A
115
56,000
56,000
0.0820...45
0.0650...52
0.3
0.4
3.5
3.5
1
5.0-13.0
1/2
111112x 9
111112x 9
Belt
Belt
2400
2.40
3.10
1725
56Y
56Y
796-1128
1150-1438
Ball
2000
2.4-3.4
4.0-5.0
5.2
6.0
5/8
7/8
49.3
52.3
AX
AX
16.2
16.2
20.2
20.2
66
58
5
5
1128
1323
3/4
195
225
195
115
175
115
05 06
4 5
901 921
40 40
50 50
122 122
184 184
Fully Hermetic Scroll
1I1I1
Copeland 3MA
1I1I142 42 66
R-410A (Puron® Refrigerant)
T×V I TXV I TXV9.0 15.7 16.6
Enhanced Copper Tubes, Aluminum Lanced Pins
1...17 [ 2...17 [ 2...17
12.6 12.6 12.6
1...17 2...17 2...17
12.6 12.6 12.6
P_peller
1...24 [ 1...24 [ 1...24
3500 3500 4500
1/8 1/8 1/4
825 825 1100
300 300 300
Enhanced Copper Tubes, Aluminum Double-Wavy Fins, Face Split
2...1598I 2...159.8 I 8...159.8
Centrifugal Type, Belt Drive
1...12x 9 1...12x 9 1...12x 9
1...12x 9 1...12x 9 1...12x 9
Belt Belt Belt
Belt Belt Belt
1200 1600 2000
0.85 0.85 0.85_.40t
0.85 1.60_.40t 1.60_.40t
1620 1620 1725
48Y 48Y 56Y
48Y 56Y 56Y
482-736 596-910 690-978
796-1128 828-1173 929-1261
Ball Ball Ball
2000 2000 2000
1.9-2.9 1.9-2.9 2.4-3.4
2.4-3.4 2.4-3.4 2.8-3.8
6.8 5.5 6.0
5.2 5.0 5.2
l& 1/2 s/8
1/2 5/8 s/8
49.3 49.3 49.3
49.3 49.3 49.3
AX AX AX
AX AX AX
16.2 16.2 16.2
16.2 16.2 16.2
20.2 20.2 20.2
20.2 20.2 20.2
48 59 58
62 69 66
555
555
736 910 978
929 1035 1128
s/4 s/4 s/4
195 195 195
195 195 225
225 225 195
115 115 115
115 115 175
175 175 115
39,200/ 56,000 39,200/ 56,000 52,500/ 75,000
52,500/ 75,000 52,500/ 75,000 79,100/113,000
79,100/113,000 79,100/113,000 105,700/151,000
56,000 56,000 75,000
75,000 75,000 113,000
113,000 113,000 151,000
0.0820...45 0.0820...45 0.0820...45
0.0650...52 0.0650...52 0.065...52
0.3 0.3 0.3
0.4 0.4 0.4
3.5 3.5 3.5
3.5 3.5 3.5
111
5.0-13.0 5.0-13.0 5.0-13.0
1/2 1/2 1/2
660 ± 10 660 ± 10 660 ± 10
505 ± 20 505 ± 20 505 ± 20
40±7 40±7 40±7
80±7 80±7 80±7
30±5 30±5 30±5
45±5 45±5 45±5
Th_waway Type
4...15 x 20 x 2 [ 4...15 x 20 x 2 [ 4...15 x 20 x 2
52,500/ 75,000
79,100/113,000
105,700/151,000
0.0820...45
0.065...52
0.3
0.4
3.5
3.5
1
5.0-13.0
1/2
4...16 x 20 x 2 [ [ 4...16 x 20 x 2
660± 10 660± 10
505 ± 20 505 ± 20
40±7 40±7
80±7 80±7
30±5 30±5
45±5 45±5

NOTES:
1. Do not locate adjacent units with flue discharge
facing economizer inlet.
Minimum clearances to be:
• Front 48 in. to combustible surfaces (18 in. to
combustible surfaces when using accessory flue
discharge deflector). When not using roof curb
(1 in.) bottom of base pan to combustible sur-
faces• When not using roof curb (0 in.) bottom of
base rail to combustible surfaces.
• Right side, front and back sides (36 in.) for
proper condenser airflow•
• Overhead (60 in.) to assure proper condenser
airflow between unit and control box (42 in. per
NEC [National Electrical Code[)•
• Between units and ungrounded surface control
box side (36 in. per NEC).
• Between unit and block or concrete wall and
other grounded surfaces control box side 42 in.).
• Horizontal supply and return, (0 in.).
2. Downshot ducts designed to be attached to acces-
sory roof curb only. If unit is mounted side supply,
it is recommended the ducts must be supported by
cross braces as done on accessory roof curb.
3. With the exception of clearance for the condenser
coil, combustible surfaces, and the damper/power
exhaust as stated in Note 1, a removable fence or
barricade requires no clearance.
4. Dimensions are from outside of base rail. Allow
0-5/16[8] on each side for top cover drip edge.
5. Units may be installed on combustible floors made
from Class A, B, C roof covering material if set on
base rails.
LEGEND
Center of Gravity
IP Direction of Airflow
9/4" D[A
STD UNIT
UNIT WEIGHT
48PG Ib kg
03 774 351
04 786 357
05 901 409
06 921 418
07 961 436
(A) (B) (C)
CORNER WEIGHT CORNER WEIGHT CORNER WEIGHT
Ib kg Ib kg Ib kg
170.1 77.1 142.3 64.5 210.3 95.4
172.7 78.3 144.5 65.5 213.5 96.8
198.0 89.8 165.7 75.2 244.8 111.0
202.4 91.8 169,4 76.8 250.2 113.5
211.2 95.8 176.7 80.2 261.1 118.4
5-5/15"
134 6
POWER SUPPLY
KNOCKOUT
(THRU CURB)
4-15/16 _
1252
] "-s 3/4"
450 S
11 I I
tURN AIR illllh " OPENINGSUPPLYAIR I'-9-914"
_NING 553 o
tTICAL II II ih VERTICAL
SnSnR.iiII ih I I 1
7070 [------
_,_rONOENSER ACCESS
CLEANOUT PANEL
RiO NOT DRILL
REAR 1' 8 578"
1524 OI
SCALE 9:32
5"114"
t13D 9] _1
S-S/16"
[84 21
4-15/16"
[125 51
1"-2-3/8'
13_521
4"-5-15/i6"
CON[TENSER COIL
1'"R'1/4"
136211
'\ 16::[3
1/2" 14 GAS
CONNECTION
-RIGHT
SIDE
(D)
CORNER WEIGHT
Ib kg
251.3 114.0
255.2 115.8
292.5 132.7
299.0 135.6
312.0 141.5
ACCESS
ROVER
5-1/R"
0'-i-1/8"
289
t
3"-r
in
Fig. 3 -- Base Unit Dimensions

Step 6 -- Install Flue Hood and Inlet Hood --
Flue hood (smaller hood), inlet hood (Ireget hood), and screens
are shipped inside the unit in the gas section. To install, open
the heat section dool: The flue hood is attached to the heat
section panel from the outside using file screws provided. See
Fig. 4 and 5.
The inlet hood is installed by inserting the hood through the
back of the heat panel. Attach the hood by inserting file screws
provided through the clearance holes in the heat panel and into
the intake hood.
NOTE: When properly installed, the flue hood will line up
with the combustion fan housing. See Fig. 6.
"_'INLET
HOOD
GAS SECTION FLUE
ACCESS DOOR HOOD
Fig. 4 -- Flue and Inlet Hood Locations
II =_IM
J_
• " i
l/_ _ _
/
HEAT EXCHANGER
SECTION MAIN BURNER SECTION
INDUCED
J DRAFT
MOTOR
-COMBUSTION
FAN HOUSING
"MAIN GAS
VALVE
Fig. 6 -- Typical Gas Heating Section
CONTROLBOX
AND COMPRESSOR
ACCESS DOOR
ELECTRICAL
OPTIONS PANEL INDOOR MOTOR
ACCESS DOOR
OUTDOOR
AIR
SCREEN
(HIDDEN)
CONDENSERCOIL
ACCESS PANEL
ECONOMIZER
HOOD
BAROMETRIC
RELIEF DAMPER
HOOD FILTER ACCESS DOOR
BABEPAN CONNECTIONS
ACCESS PANEL
Fig. 5 -- Panel and Filter Locations
GAS SECTION
ACCESS DOOR

Step 7 -- Install External Trap for Condensate
Drain -- The unit's 3h-in. condensate drain connections am
located on the bottom and side of file unit. Unit discharge
connections do not determine the use of drain connections;
either &ain connection can be used with vertic;d or horizontal
applications. See Fig. 3 for locations.
When using the standmd side drain connection, make sure
the plug (red) in the ;alternate bottom connection is tight before
installing the unit. See Fig. 7.
To use the bottom &'ain connection for a roof curb installa-
tion, relocate the factory-installed plug (red) fiom the bottom
connection to the side connection. A q2-in, socket extension
can be used to remove the plug. See Fig. 7. The piping for the
condensate &ain and extern;fl trap can be completed after the
unit is in place.
All units must have an external trap for condensate drain-
age. Install a trap at least 4-in. deep and protect against freeze-
up. If drain line is installed downstremn from the external trap,
pitch the line away fi_m the unit at 1-in. per 10 ft of run. Do not
use a pipe size smaller than the unit connection (3/4-in.). See
Fig. 8 and 9.
The 48PG units are provided with a removable condensate
pan for ease of cleaning. Refer to Cleaning section on page 37
for more information. It is recommended that a union be placed
between the unit and condensate drainage to ease the removal
of file pan during servicing. Adequate cle;uance should be
allowed if removal of condensate pan is required. Allow 54-in.
between condensate pan access panel and any obstruction for
complete removal.
ONEJN.PER BASE I I I IL_
lOFT OFUNE X RAIL --l--]_...J/t
\OPEN 2" MINI [ III
\VENT I I I III
TDOFIRINO_F" "_--I
1===4 DRAIN PLUG
_F-
SEE
NOTE
t
,w_ROOF
CURB
NOTE: Trapshould be deep enough to offset maximum unit static
difference.A 4-in.trap is recommended.
Fig. 9- Condensate Drain Piping Details
SIDE DRAIN
PLUG
Fig. 7 -- Condensate Drain Pan
BOTTOM DRAIN
PLUG
CONDENSATE
PANACCESS
PANEL
OPTIONAL UNIONS
TO ALLOW FOR CONDENSATE
PAN REMOVAL
Fig. 8 -- External Trap for Condensate Drain

Step 8 -- Install Gas Piping -- Unit is equipped for
use with natural gas. Refer to local building codes, or in the
absence of local codes, to ANSI Z223.1-1atest year and
addendum Z223.1A-latest year entitled HFGC. In Canada, in-
stallation must be in accordance with the CANI.BI49.1 and
CAN 1.B 149.2 installation codes for gas burning appliances.
Support gas piping as shown in the table in Fig. 10. For
example, a JV4-in. gas piping must have one field-fabricated
support beam every 8 11. Therefore, an 18-1l long gas pipe
would have a minimum of 3 support beams. See Fig. 10 for
typical pipe guide and locations of external manual gas shutoff
valve.
Install field-supplied manu_fl gas shutoff valve with a l/8-in.
NPT pressure tap for test gage connection at unit. The pressure
tap is located on the gas manifold, adjacent to the gas v_flve.
Field gas piping must include sediment trap and union. See
Fig. 11. Inst_dl a field-supplied gas regulatol:
Do not pressure test gas supply while connected to unit.
Always disconnect union before servicing. Damage to
equipment or personal injury may result.
,m X _'1
GAS I
{' I'MANUALaASREGU TOR*I
/ BASEUNI T _J_TOFF VALVE* ,_
.......................................I}1
T-q T OR,P E PERNFGC*
B sE+L ]i '-"OO CUR /
FIELD-FABRICATED
SUPPORT*
FROM GAS METER
LEGEND
NFGC -- National Fuel Gas Code
*Field supplied.
NOTE: Follow all local codes.
STEEL PIPE NOMINAL I SPACING OF SUPPORTS
DIAMETER (in.) I X DIMENSION (ft)
1/2 6
3/4 or 1 8
11/4 or larger 10
Fig. 10 -- Gas Piping Guide (With Accessory
Thru-the-Curb Service Connections)
MANUAL SHUTOFF
(FIELD SUPPLIED) rq-i
fSUPPLY
PRESSURE TAP
(1/8" NPT PLUG)
UNIT UN]OL_'_N _ "+--'-- SEDIMENT TRAP
Fig. 11 -- Field Gas Piping
I IMPORTANT: Natural gas pressure at unit gas connection I
must not be less than 5.0 in. wg or greater than 13.0 in. wg I
for all heat sizes.
Size gas-supply piping for 0.5-in. wg maximum pressure
diop. Do not use supply pipe smaller than unit gas connection.
Step 9 -- Make Electrical Connections
FIELD POWER SUPPLY -- All 208/230-v units _u'e factory
wired for 230-v power supply. If the 208/230-v unit is to be
connected to a 208-v power supply, the transformer must be re-
wired by moving the black wire with the l/4-in, female quick
connector flom the 230-volt connection and moving to
the 200-volt l/4-in, male termimd on the primary side of the
transformel:
Refer to unit label diagram for additional information. All
field wiring must comply with NEC (National Electrical Code)
tuld local codes. Size wire based on MCA (Minimum Circuit
Amps) on the unit informative plate. Leads are provided for
field wire connections. Use UL (Underwriters' Laboratories)
approved copper/aluminum connectol:
When installing units, provide safety disconnect per NEC
Article 440 or local codes. For non-fused disconnects, size the
disconnect according to the sizing &_ta provided in the electri-
cal data tables. Ifa lilsed disconnect is used, determine the min-
imum size for the switch based on the disconnect sizing data
provided in the electric:d data tables and then coordinate the
disconnect housing size to accommodate the Maximum Over-
current Protection (MOCP) device size as maned on the unit
infonnative plate. See Tables 2A and 2B.
See Fig. 12 for power wiring connection to unit leads and
equipment ground.
Route power and ground lines through control box end
panel or unit basepan (see Fig. 3) to connections as shown on
unit wiring diagram and Fig. 12. Factory leads may be wired
directly to the disconnect.
The correct power phasing is cdtic:d to the operation of the
scroll compressors. An incorrect phasing will result in
compressor shutdown on thermal overload and possible
&_mage to compressol: Should this occm; power phase cor-
rection must be made to the incoming powec
Unit cabinet must have an uninterrupted, unbroken electri-
cal ground to minimize the possibility of pel_onal injury if
an electrical fault should occm: This ground may consist of
electric_d wire connected to unit ground lug in control com-
partment, or conduit approved for electrical ground when
installed in accor&mce with NEC; ANSI/NFPA (National
Fire Protection Association), latest edition, and local elec-
triced codes. Do not use gas piping as an electrical ground
Failure to follow this warning could result in the installer
being liable for personal injury of others.
Field winng must conform to temperature limitations for
type "T" wire. All field wiring must comply with NEC and
local requirements.
Operating voltage to compressor must be within voltage
range indicated on unit nameplate. On 3-phase units, voltages
between phases must be balanced within 2%.
Unit failure as a result of operation on improper line voltage
or excessive phase imbalance constitutes abuse and may cause
&image to electrical components.

----I I
I
ow
coo-
E_
I
r
I
I
I--
I
I
FIELD FACTORY
POWER _ POWER
WIRING _ WIRING
C.A1
EQUIP GND
LEGEND
C.A1 -- Compressor Contactor (A1)
EQUIP -- Equipment
GND -- Ground
NEC -- National Electrical Code
NOTE: The maximum wire size for C.A1 is 2/0.
Fig. 12- Field Power Wiring Connections
FIELD CONTROL WIRING -- Unit can be controlled with
a Carrier-approved accessory themlostat. Install thermostat ac-
cording to the installation instructions included with accessory.
[x_cate thermostat assembly on a solid interior wall in the con-
ditioned space to sense average temperature.
Route thermostat cable or equiv_dent single leads of colored
wire from subbase temlinals through conduit into unit to low-
voltage connections as shown on unit label wiring diagram and
in Fig. 13.
NOTE: For wire runs up to 50 ft, use no. 18 AWG (American
Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft,
use no. 16 AWG insulated wire (35 C minimum). For over
75 ft, use no. 14 AWG insulated wire (35 C minimum). All
wire larger than no. 18 AWG cannot be directly connected at
the thermostat and will require a junction box and splice at the
thermostat.
Set heat anticipator settings as follows:
STAGE 1 STAGE 1 AND 2
VOLTAGE (W1) ON (Wl AND W2) ON
All 0.3 0.4
Settings may be changed slightly to provide a greater degree
of comfort for a particular installation.
TB1
THERMOSTAT ASSEMBLY
REMOVABLE JUMPER
j_ IIIIIII
Fig. 13- Field Control Thermostat Wiring
10

Table 2A -- Electrical Data -- Units Without Optional Convenience Outlet
UNIT
48PG
03
04
05
06
07
NOMINAL POWER VOLTAGE
SUPPLY RANGE
Volts-Ph-Hz MIn Max RLA
208/230-1-60 187 253 12.8
208/230-1-60 187 253 15.4
208/230-3-60 187 253 11.5
460-3-60 414 506 5.1
575-3-60 518 633 4.3
208/230-1-60 187 253 20.5
208/230-3-60 187 253 14.6
460-3-60 414 506 7.1
575-3-60 518 633 5.1
208/230-1-60 187 253 26.9
208/230-3-60 187 253 17.6
460-3-60 414 506 7.7
575-3-60 518 633 6.1
208/230-3-60 187 253 20.5
460-3-60 414 506 9.6
575-3-60 518 633 7.6
COMPRESSOR OFM PWR
EXH IFM IFM FAN MOTOR
LRA Oty FLA(ea) FLA (ea) TYPE FLA FLA
STD 4.9
ALT 4.9
60 1 1.0 0.52
STD 4.9
1.4 ALT 4.9
STD 4.9
ALT 4.9
83 1 1.8 0.52
STD 4.9
1.4 ALT 4.9
STD 4.9
ALT 4.9
77 1 1.0 0.52
STD 4.9
1.4 ALT 4.9
STD 2.1
ALT 2.1
35 1 0.5 0.30
STD 2.1
0.6 ALT 2.1
STD 2.1
ALT 2.1
31 1 0.5 0.24
STD 2.1
1.4 ALT 2.1
STD 4.9
ALT 7.0
109 1 1.0 0.52
STD 4.9
1.4 ALT 7.0
STD 4.9
ALT 5.2
91 1 1.0 0.52
STD 4.9
1.4 ALT 5.2
STD 2.1
ALT 2.8
46 1 0.5 0.30
STD 2.1
0.8 ALT 2.8
STD 2.1
ALT 2.0
34 1 0.5 0.24
STD 2.1
1.4 ALT 2.0
STD 4.9
ALT 7.0
145 1 1.5 0.52
STD 4.9
1.4 ALT 7.0
STD 5.2
ALT 5.2
123 1 1.5 0.52
STD 5.2
1.4 ALT 5.2
STD 2.8
ALT 2.8
50 1 0.8 0.30
STD 2.8
0.8 ALT 2.8
STD 2.0
ALT 2.0
40 1 0.8 0.24
STD 2.0
1.4 ALT 2.0
STD 5.2
ALT 7.5
149 1 1.5 0.52
STD 5.2
1.4 ALT 7.5
STD 2.8
ALT 3.4
75 1 0.8 0.30
STD 2.8
0.8 ALT 3.4
STD 2.0
ALT 2.8
54 1 0.8 0.24
STD 2.0
1.4 ALT 2.8
COMBUSTION POWER SUPPLY DISCONNECT SIZE
MCA MOCP FLA LRA
21.9/21.9 25/25 22/22 74/74
21.9/21.9 25/25 22/22 74/74
23.3/23.3 25/25 23/23 76/76
23.3/23.3 25/25 23/23 76/76
25.2/25.2 30/30 24/24 97/97
25.2/25.2 30/30 24/24 97/97
26.6/26.6 30/30 26/26 99/99
26.6/26.6 30/30 26/26 99/99
20.3/20.3 25/25 20/20 91/91
20.3/20.3 25/25 20/20 91/91
21.7/21.7 25/25 22/22 93/93
21.7/21.7 25/25 22/22 93/93
9 15 9 42
9 15 9 42
9.6 15 10 43
9.6 15 10 43
8 15 8 37
8 15 8 37
9.4 15 10 39
9.4 15 10 39
31.5/31.5 35/35 30/30 123/123
33.6/33.6 35/35 33/33 148/148
32.9/32.9 35/35 32/32 125/125
35.0/35.5 40/40 34/34 150/150
24.2/24.2 25/25 24/24 105/105
24.5/24.5 25/25 24/24 123/123
25.6/25.6 30/30 25/25 107/107
25.9/25.9 30/30 26/26 125/125
11.5 15 11 53
12 15 12 62
12.1 15 12 54
12.6 15 12 63
9 15 9 40
8.9 15 9 46
10.4 15 10 42
10.3 15 10 48
40.0/40.0 45/45 38/38 168/160
42.1/42.1 45/45 41/41 185/185
41.4/41.4 45/45 40/40 162/162
43.5/43.5 50/50 42/42 187/187
28.7/28.7 30/30 28/28 156/156
28.7/28.7 30/30 28/28 156/156
30.1/30.1 35/35 30/30 158/158
30.1/30.1 35/35 30/30 158/158
13 15 13 67
13 15 13 67
13.6 15 13 68
13.6 15 13 68
10.4 15 10 53
10.4 15 10 53
11.8 15 12 55
11.8 15 12 55
32.3/32.3 35/35 31/31 182/182
34.6/34.6 35/35 34/34 208/208
33.7/33.7 35/35 33/33 184/184
36.0/36.0 40/40 36/36 210/210
15.4 20 15 92
16.2 20 16 105
16 20 16 93
16.8 20 17 106
12.3 15 12 67
13.1 15 13 78
13.7 15 14 69
14.5 15 14 88
LEGEND
FLA -- Full Load Amps
HACR -- Heating, Air Conditioning and Refrigeration
IFM -- Indoor (Evaporator) Fan Motor
LRA -- Locked Rotor Amps
MCA -- Minimum Circuit Amps
MOCP -- Maximum Overcurrent Protection
NEC -- National Electrical Code
OFM -- Outdoor (Condenser) Fall Motor
RLA -- Rated Load Amps
Example: Supply voltage is 230-3-60.
C,, ° c AB=224v
BC = 231 v
AC = 226 v
Average Voltage = 224 + 231 + 226
3
681
="W-
=227
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equipment
(refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall
be fuse or HACR breaker. Canadian units may be fuse or circuit breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply w_ltage is greater than 2%.
Use the following formula to determine the percent of voltage imbalance.
% Voltage Imbalance
= 100 x max voltage deviation from average voltage
average voltage
Determine maximum deviation from average voltage.
(AB) 227 - 224 = 3 v
(BC) 231 - 227 = 4 v
(AC) 227 - 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
4
% Voltage Imbalance = 100 x 227
= 1.76%
This amount of phase imbalance is satisfactory as it is below the maximum allowable
2%.
IoMcPiOelRecTArNT:ul[li_eo_Ul[_)_yyWlt_alg_Pthelye imbal ..... i....... than 2°/o, contact the I
1!

Table 2B -- Electrical Data -- Units With Optional Convenience Outlet
UNIT
48PG
NOMINAL POWER
SUPPLY
Volts-Ph-Hz
208/230-1-60
208/230-1-60
208/230-3-60
460-3-60
575-3-60
208/230-1-60
208/230-3-60
460-3-60
575-3-60
208/230-1-60
208/230-3-60
460-3-60
575-3-60
208/230-3-60
460-3-60
575-3-60
VOLTAGE COMPRESSOR OFM PWR COMBUSTION POWER SUPPLY
RANGE EXH IFM IFM FAN MOTOR
MIn Max RLA LRA Qty FLA FLA (ea) TYPE FLA
(ea) FLA MCA MOCP
STD 4.9 26.7/26.7 30/30
ALT 4.9 26.7/26.7 30/30
187 253 12.8 60 1 1.0 0.52
STD 4.9 28.1/28.1 30/30
1.4 ALT 4.9 28.1/28.1 30/30
STD 4.9 30.0/30.0 30/30
ALT 4.9 30.0/30.0 30/30
187 253 15.4 83 1 1.0 0.52
STD 4.9 31.4/31.4 35/35
1.4 ALT 4.9 31.4/31.4 35/35
STD 4.9 25.1/25.1 30/30
ALT 4.9 25.1/25.1 30/30
187 253 11.5 77 1 1.0 0.52
STD 4.9 26.5/26.5 30/30
1.4 ALT 4.9 26.5/26.5 30/30
STD 2.1 11.2 15
ALT 2.1 11.2 15
414 506 5.1 35 1 0.5 0.30
STD 2.1 11.8 15
0.6 ALT 2.1 11.8 15
STD 2.1 9.7 15
ALT 2.1 9.7 15
518 633 4.3 31 1 0.5 0.24
STD 2.1 11.1 15
1.4 ALT 2.1 11.1 15
STD 4.9 36.3/36.3 40/40
ALT 7.0 38.4/38.4 40/40
187 253 20.5 109 1 1.0 0.52
STD 4.9 37.7/37.7 40/40
1.4 ALT 7.0 39.8/39.8 40/40
STD 4.9 29.0/29.0 30/30
ALT 5.2 29.3/29.3 30/30
187 253 14.6 91 1 1.0 0.52
STD 4.9 30.4/30.4 35/35
1.4 ALT 5.2 30.7/30.7 35/35
STD 2.1 13.7 15
ALT 2.6 14.2 15
414 506 7.1 46 1 0.5 0.30
STD 2.1 14.3 15
0.6 ALT 2.6 14.8 15
STD 2.1 10.7 15
ALT 2.0 10.6 15
518 633 5.1 34 1 0.5 0.24
STD 2.1 12.1 15
1.4 ALT 2.0 12 15
STD 4.9 44.8/44.8 50/50
ALT 7.0 46.9/46.9 50/50
187 253 26.9 145 1 1.5 0.52
STD 4.9 46.2/46.2 50/50
1.4 ALT 7.0 48.3/48.3 50/50
STD 5.2 33.5/33.5 35/35
ALT 5.2 33.5/33.5 35/35
187 253 17.6 123 1 1.5 0.52
STD 5.2 34.9/34.9 35/35
1.4 ALT 5.2 34.9/34.9 35/35
STD 2.6 15.2 20
ALT 2.6 15.2 20
414 506 7.7 50 1 0.8 0.30
STD 2.6 15.8 20
0.6 ALT 2.6 15.8 20
STD 2.0 12.1 15
ALT 2.0 12.1 15
518 633 6.1 40 1 0.8 0.24
STD 2.0 13.5 15
1.4 ALT 2.0 13.5 15
STD 5.2 37.1/37.1 40/40
ALT 7.5 39.4/39.4 40/40
187 253 20.5 149 1 1.5 0.52
STD 5.2 38.5/38.5 40/40
1.4 ALT 7.5 40.8/40.8 45/45
STD 2.6 17.6 20
ALT 3.4 18.4 20
414 506 9.6 75 1 0.8 0.30
STD 2.6 18.2 20
0.6 ALT 3.4 19 20
STD 2.0 14 15
ALT 2.8 14.8 15
518 633 7.6 54 1 0.8 0.24
STD 2.0 15.4 20
1.4 ALT 2.8 16.2 20
DISCONNECT SIZE
FLA LRA
27/27 79/79
27/27 79/79
29/29 81/81
29/29 81/81
30/30 102/102
30/30 102/102
32/32 104/104
32/32 104/104
26/26 96/96
26/26 96/96
27/27 98/98
27/27 98/98
11 44
11 44
12 45
12 45
10 39
10 39
12 41
12 41
36/36 128/128
38/38 153/153
37/37 130/130
40/40 155/155
29/29 110/110
29/29 128/128
31/31 112/112
31/31 130/130
14 55
14 64
14 56
15 65
11 42
11 48
12 44
12 50
44/44 165/165
46/46 190/190
45/45 167/167
48/48 192/192
33/33 161/161
33/33 161/161
35/35 163/163
35/35 163/163
15 69
15 69
16 70
16 70
12 55
12 55
14 57
14 57
37/37 187/187
39/39 213/213
38/38 189/189
41/41 215/215
17 94
18 107
18 95
19 108
14 69
15 80
16 71
16 82
LEGEND
FLA -- Full Load Amps
HACR -- Heating, Air Conditioning and Refrigeration
IFM -- Indoor (Evaporator) Fan Motor
LRA -- Locked Rotor Amps
MCA -- Minimum Circuit Amps
MOCP -- Maximum Overcurrent Protection
NEC -- National Electrical Code
OFM -- Outdoor (Condenser) Fan Motor
RLA -- Rated Load Amps
Example: Supply voltage is 230-3-60.
AB C AB = 224v
(_ BC = 231 v
AC = 226 v
C _JS Average Vo,tage =
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equipment
(refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall
be fuse or HACR breaker. Canadian units may be fuse or circuit breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply voltage is greater than 2%.
Use the following formula to determine the percent of voltage imbalance.
% Voltage Imbalance
= 100 x max voltage deviation fron average voltage
average voltage
224 + 231 + 226
3
681
3
= 227
Determine maximum deviation from average voltage.
(AB) 227 -224 = 3 v
(BC) 231 -227 = 4 v
(AC) 227 =226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
4
% Voltage Imbalance = 100 x 22"_"
= 1.76%
This amount of phase imbalance is satisfactory as it is below the maxinum allowable
2%.
I ° ]
IMPORTANT: If the supply voltage phase imbalance is more than 2Yo, contact the
local electric utility company immediately.
12

Step 10- Optional EconoMi$er IV- The option-
al EconoMi$er IV comes from the factory fnlly wiled. Out-
door air hoods must be installed. No field wiring or assembly
is required for standard outdoor c_h'ybulb changeover opera-
tion. Field wiring of accessory sensors is required for diffelent
operational modes.
INSTALL OUTDOOR AIR HOODS -- Perform the follow-
ing procedure to install the outdoor-air hoods:
1. Economizer and barometric relief hoods are located in the
condenser section under the slanted coil for shipping. See
Fig. 14. Barometric relief/power exhaust hood is shipped
inside of economizer hood. Remove screws that secure
the wooden rails of the hood assemblies to the unit. Save
screws. Slide complete assembly from condenser section.
2. Remove the screws that secure the economizer and
barometric relief/power exhaust hoods to the wooden
railing. Discmd or lecycle wooden rails. Save screws.
3. The barometric relief dmnper is secured to the economiz-
er panel for shipping. Remove the screw holding the
barometric relief damper to the panel. Damper should be
fiee to swing open during operation. See Fig. 15.
4. Hang the barometric relieffpower exhaust hood on the
mounting fange on the economizer panel. Secure hood to
panel with sclews saved from Step 2. See Fig. 15 and 16.
5. Align hole in flange of economizer panel with left edge of
hood. Hang economizer hood on the top flange of the
economizer panel by rotating hood until top flange of the
economizer hood engages the bent flange on the econo-
mizer panel. Rotate hood until hood is flush with the
economizer panel. Hood will support itself fiom flange.
Align holes in hood with holes in panel and secure
hood to panel with sclews saved from Step 2. See Fig. 15
and 17.
ECONOMISER IV STANDARD SENSORS
Outdoor Air Temperature (OAT) Sensor -- The outdoor air
temperature sensor is a 10 to 20 mA device used to measure the
outdoor-air temperature. The outdoor-air temperature is used to
determine when the EconoMiSer IV can be used for flee cool-
ing. The sensor is factory-installed on the EconoMi$er IV in
the outdoor airstremn. The operating range of temperature
measurement is 40 to 100 E
MOUNTING /
FLANGE
ECONOMIZER
HOOD
POWER EXHAUST/
BAROMETRIC
RELIEF HOOD
\
ECONOMIZER BAROMETRIC
PANEL RELIEF DAMPER SCREW
Fig. 15- Hood Installation
POWER EXHAUST/
BAROMETRIC
RELIEF HOOD
/
/
/
/POWER EXHAUST/
// BAROMETRIC
/,//' / RELIEF HOOD
Fig. 16- Barometric Relief/Power Exhaust
Hood Flange
WOODEN RAILS _ ECONOMIZER
HOOD
Fig. 14 -- Economizer and Barometric
Relief/Power Exhaust Hoods Shipping Positions
MOUNTING
FLANGE
ECONOMIZER
HOOD
Fig. 17- Economizer Flange
13

Mixed Air Temperature (MAT) Sensor -- The mixed tdr
temperature sensor is a 3 K thermistor located at the discharge
of the indoor fan. The sensor is mounted through the side plate
of the blower. The sensor has blue leads. This sensor is factory
installed. The operating range of temperature measurement is
0°to 158E
Outdoor Air Lockout Sensor -- The EconoMiSer IV is
equipped with a temperature limit switch located in the outdoor
airstream which is used to lock out the compressors below a
50 F mnbient temperature.
ECONOM[$ER [V CONTROLLER WIRING AND OPER-
ATIONAL MODES -- Determine the EconoMiSer IV control
mode before inst',_ling sensol_ and accessories. Different sensors
_ue required for different control modes, and a number of
accessories m'e available. Refer to NiNe 3. The EconoMiSer IV
is supplied from the factory with a mixed air temperature
sensor and an outdoor air temperature sensol: This allows for
operation of the EconoMiSer IV with outdoor air din bulb
changeover control. Additional accessories can be added to
allow for different types of changeover control and operation
of the EconoMiSer IV and unit. See Fig. 18 for wiring.
Outdoor Dry Bulb Changeover -- The standard controller is
shipped from the factory configured for outdoor dry bulb
changeover control. The outdoor air and mixed air temperature
sensors are included as standard. For this control mode, the out-
door temperature is compared to an adjustable set point selected
on the control. If the outdoor-air temperature is above the set
point, the EconoMiSer IV will adjust the outside-air dmnpers to
minimum position. If the outdoor-air temperature is below the
set point, the position of the outside-air &tmpers will be con-
trolled to provided free cooling using outdoor _il: When in this
mode, the LED next to the free cooling set point potentiometer
will be on. The changeover temperature set point is controlled
by the flee cooling set point potentiometer located on the con-
trol. The sc_fle on the potentiometer is A, B, C, and D. See
Fig. 19 for the corresponding temperature changeover values.
Differential Dry Bulb Control -- For differential din bulb
control the standard outdoor din bulb sensor is used in conjunc-
tion with an additional accessoly din bulb sensor (part number
CRTEMPSN002A00). The accessoly sensor must be mounted
in the return airstream. Connect the return air temperature sen-
sor to the SR terminal (aller removing the 620-ohm resistor)
and to file + terminal on file controllel: See Fig. 20.
In this mode of operation, the outdoor air temperature is
compared to the return air temperature and the lower tempera-
ture airstream is used for cooling. When using this mode of
changeover control, turn the enthalpy setpoint potentiometer
fully clockwise to the D setting. See Fig. 21.
Outdoor Enthalpy Changeover -- For enthalpy control, ac-
cessory enthalpy sensor (p_u-t number HH57AC078) is
required. Replace the standard outdoor dry bulb temperature
sensor with the accessory enthalpy sensor in the same mount-
ing location. When the outdoor air enthalpy rises above the
outdoor enthalpy changeover set point, the outdoor-air &tmper
moves to its minimum position. The outdoor enthalpy
changeover set point is set with the outdoor enthalpy set point
potentiometer on the EconoMiSer IV controller The set points
are A, B, C, and D. See Fig. 22. The factory-installed 620-ohm
jumper must be in place across terminals SR and + on the
EconoMiSer IV controllel: See Fig. 20.
Differential Enthalpy Control -- For differential enth_dpy
control, the EconoMiSer IV controller uses two enthalpy sen-
sors (CRENTDIF004A00), one in the outside air and one in the
return air duct. The EconoMiSer IV controller compares the
outdoor air enth_flpy to the return air enthalpy to determine
EconoMiSer IV use. The controller selects the lower enth_flpy
air (return or outdoor) for cooling. For exalnple, when the out-
door air has a lower enthalpy than the return ail: the
EconoMiSer IV opens to bring in outdoor air for free cooling.
Replace the stan&trd outside air dry bulb temperature sensor
with the accessory enthalpy sensor in file salne mounting loca-
tion. Mount the return air enthalpy sensor in the return air duct.
The return tdr enth_flpy sensor is wired to terminals SR and + on
the EconoMiSer IV controllel: See Fig. 20. The outdoor
enthalpy changeover set point is set with the outdoor enthalpy
set point potentiometer on the EconoMiSer IV controllel: When
using this mode of changeover control, turn the enth_dpy set
point potentiometer fully clockwise to the D setting.
Indoor Air Quality (IAQ) Sensor Input -- The IAQ input
can be used for demand control ventilation control based on the
level of CO2 measured in the space or return air duct.
Mount the optional IAQ sensor according to manufacturer
specifications. The IAQ sensor should be wired to the AQ and
AQI terminals of the controllel: Adjust the DCV potentiome-
ters to correspond to the DCV voltage output of the indoor air
qu_flity sensor at the user-determined set point. See Fig. 23.
If a separate field-supplied transformer is used to power the
IAQ sensol; the sensor must not be grounded or the
EconoMiSer IV control board will be &imaged. See Fig. 18.
Power Exhaust -- The factory-installed power exhaust will be
factory wired and installed. If an accessory power exhaust is to
be installed, see the accessory power exhaust installation in-
structions included with the power exhaust for inst_fllation and
wiring. The wiring plug on the power exhaust is connected to
wiring harness plug PLI-3,4.
ECONOMI$ER IV WITH SINGLE
APPLICATION ENTHALPY SENSOR
Accessories Required
Outdoor Air Dry Bulb CRTEMPSN002A00*
Differential Dry Bulb (2) CRTEMPSN002A00*
Single Enthalpy None. The single enthalpy sensor is factory installed.
Differential Enthalpy CRENTDIF004A00*
002 for DCV Control using a
Wall-Mounted CO2 Sensor
CO2 for DCV Control using a
Duct-Mounted CO2 Sensor
Table 3 -- EconoMi$er IV Sensor Usage
ECONOMI$ER IV WITH OUTDOOR AIR
DRY BULB SENSOR
Accessories Required
None.Theoutdoorairdry bulbsensorisfactoryinstalled.
CRTEMPSN002A00*
HH57AC078
HH57AC078
and
CRENTDIF004A00*
33ZCSENCO2
33ZCSENCO21-
and CRCBDIOX005A001-1-
33ZCASPCO2**
*CRENTDIF004A00 and CRTEMPSN002A00 accessories are used on
many different base units. As such, these kits may contain parts that
will not be needed for installation.
1-33ZCSENCO2 is an accessory CO2 sensor.
33ZCSENCO2
33ZCSENCO21-
and CRCBDiOX005A001-1-
33ZCASPCO2**
**33ZCASPCO2 is an accessory aspirator box required for duct-
mounted applications.
1-1-CRCBDIOX005A00 is an accessory that contains both 33ZCSENCO2
and 33ZCASPCO2 accessories.
14

RED
REMOVE JUMPER WHEN
INSTAIIXNG OCCUPAMCY
SWIICH
NOTE: See page 45 for Legend.
GRA
RED
ECONOMIZER
MOTOR
ECONOMIZER ACCY/FIOP ]
,m i
151 I GRA MINIMUM
I POS[T!ON
I ADJUSTMENI i
b _ ?L2 1
APOWER EXHAUS1
ACCY/FIOP
RED ]460V ONLY
_PLZ
2
F[EL_ INSTALLED
R_MOIE ECONOMIZER
ENABLE SWITCH
DISCONNECT PiNK A_ YELLOW
REMOVE 620G RESISTOR
BETWEEN SR+ AND SR WNEN
IA ENTNALP¥ OR RETURN AIR
SENSO_ IS [NSTAI_E_
PECI
PEC2
EC_
Fig. 18 -- EconoMi$er IV Wiring
19
18
17
16-
15
<
E14
13
12
11
10
94O
I
"_._ LED ON
-- - LED OFF LED ON
--LED ON
45 50 55 60 65 70 75 80
DEGREES FAHRENHEIT
LED ON- --
I
85 90 95 100
Fig. 19 -- Temperature Changeover Set Points
-///
[
xH
Set
N 2 OV
P1 r_ex_ )
PU K-_in
T _l_Jl Open
DCV
V(_IMa_
2 OV
_TAQ U -- DCV
SO+ H 2V_IOV et
sowAJI
SR+ Free
I oo,©
s____1_o
24 24 Vac
Vac COM
HO_ll_ _,
5
3B4
E F [_'_ EF1
Fig. 20 -- EconoMi$er IV Control
m
15

EXHAUST
FAN SET POINT
LED LIGHTS
WHEN EXHAUST
CONTACT IS MADE
MINIMUM DAMPER
POSITION SETTING
MAXIMUM DAMPER
DEMAND CONTROL
VENTILATION SET POINT
LED LIGHTS WHEN_
DEMAND CONTROL
VENTILATION INPUT
IS ABOVE SET POINT
DEMAND CONTROL
VENTILATION SET POINT
LED LIGHTS WHEN
OUTDOOR AIR IS
AQ1 DCV DCV I J% 0 f
SUITABLE FOR
FREE COOLING ENTHALPY
CHANGEOVER SET POINT
Fig. 21 -- EconoMiSer IV Controller Potentiometer
and LED Locations
CONTROL CONTROL POINT
CURVE APPROX. °F (°C)
AT 50% RH
A 73 (23)
B 70 (21)
C 67 (19)
D 63 (17)
85 90 95 100 105 110
(29) (32) (35) (38) (41) (43)
\1 /I \
35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110
(2) (4) (7) (10) (13) (16) (18) (21) (24) (27) (29) (32) (35) (38) (41) (43)
APPROXIMATE DRY BULB TEMPERATURE i °F (°C)
Fig. 22 -- Enthalpy Changeover Set Points
LIMIT
CURVE
16

6000
5000
z
O 4ooo
0c
r_ 3000
I.L,
z
OO 2000
LLI
O
z 1000
<
CO2 SENSOR MAX RANGE SETTING
1000 ppm
_1100 ppm
2345678
DAMPER VOLTAGE FOR MAX VENTILATION RATE
Fig. 23 -- 002 Sensor Maximum Range Setting
Exhaust Set Point Adjustment -- The exhaust set point will
determine when the exhaust fan runs based on damper position
(if accessory power exhaust is installed). The set point is modi-
fied with the Exhaust Fan Set Point (EXH SET) potentiometel:
The set point represents the damper position above which the
exhaust fans will be turned on. When thele is a call for exhaust,
the EconoMiSer IV controller provides a 45 _+15 second delay
before exhaust fan activation to allow the dampers to open.
This delay allows the dalnper to reach the appropriate position
to avoid unnecessary fan overload.
Minimum Position Control -- There is a minimum damper
position potentiometer on the EconoMiSer IV controllel: See
Fig. 21. The minimum dalnper position mainttdns the mini-
mum airflow into the building during the occupied period.
When using demand ventilation, the minimum damper po-
sition replesents the minimum ventilation position for VOC
(volatile organic compounds) ventilation requirements. The
maximum demand ventilation position is used for fully occu-
pied ventilation.
When demand ventilation control is not being used, the
minimum position potentiometer should be used to set the
occupied ventilation position. The maximum demand ventila-
tion position should be turned liflly clockwise.
Adjust the minimum position potentiometer to allow the
minimum amount of outdoor air, as requiled by local codes, to
enter the building. Make minimum position adjustments with
at least 10° F temperature difference between the outdoor and
return-air temperatures.
To determine the minimum position setting, perform the
following procedure:
1. Calculate the appropriate mixed-air temperature using the
following formula:
(To x OA) + (TR x RA) = TM
To = Outdoor-Air Temperatme
OA = Percent of Outdoor Air
TR = Return-Air Temperature
RA = Percent of Return Air
TM = Mixed-Air Temperature
As an exmnple, if local codes require 10% outdoor air
during occupied conditions, outdoor-air temperature is
60 IF.and return-air temperature is 75 IF.
(60 x. 10) + (75 x .90) = 73.5 F
2. Disconnect the mixed-air sensor from terminals T and
TI.
3. Ensure that the factory-installed jumper is in place across
terminals P and PI. If lemote damper positioning is being
used, make sure that the terminals are wired according to
Fig. 18 and that the minimum position potentiometer is
turned fully clockwise.
4. Connect 24 vac across terminals TR and TRI.
5. Carefully adjust the minimum position potentiometer
until the measured mixed air temperature matches the cal-
culated v_due.
6. Reconnect the mixed air sensor to termin_ds T and TI.
Remote control of the EconoMiSer IV damper is desirable
when requiring additional temporary ventilation. If a field-
supplied remote potentiometer (Honeywell p_ut number
$963B1128) is wired to file EconoMiSer IV controller, the
minimum position of the damper can be controlled from a
remote location.
To control the minimum damper position remotely, remove
the factory-installed jumper on the P and PI terminals on the
EconoMiSer IV controllel: Wire file field-supplied potentiome-
ter to the P and PI terminals on the EconoMiSer IV controllel:
See Fig. 20.
Damper Movement -- When the EconoMiSer IV board re-
ceives initial power, it can take the damper up to 21/2 minutes
befole it begins to position itself. After the initial positioning,
subsequent changes to damper position will take up to 30 sec-
onds to initiate. Dmnper movement from lifll open to full
closed (or vice versa) takes 21/2 minutes.
Thermostats -- The EconoMiSer IV control works with con-
ventional thermostats that have a YI (cool stage 1), Y2 (cool
stage 2), WI (heat stage 1), W2 (heat stage 2), and G (fan). The
EconoMiSer IV control does not support space temperature
sensors. Connections me made at the thermostat terminal con-
nection board located in file main control box.
Pressure Drop -- See Fig. 24 and 25 for EconoMiSer IV pres-
sure drop. Evaporator fan may need to be adjusted.
Demand Control Ventilation(DCV) -- When using the
EconoMiSer IV for demand control ventilation, there me some
equipment selection criteria which should be considered. When
selecting the heat capacity and cool capacity of the equipment,
file maximum ventilation rate must be ev_duated for design
conditions. The maximum damper position must be calculated
to provide the desired fresh all:
Typically the maximum ventilation rate will be about 5 to
10% more than the typical cfm lequiled per person, using
normal outside air design criteria.
A proportional anticipatory strategy should be taken with
the following conditions: a zone with a large area, varied
occupancy, and equipment that cannot exceed the required
ventilation rate at design conditions. Exceeding file required
ventilation rate means the equipment can condition air at a
maximum ventilation rate that is greater than file required
ventilation rate for maximum occupancy. A proportional-
anticipatory strategy will cause file fi'esh air supplied to
increase as file room CO2 level increases even though the CO2
set point has not been reached. By the time the CO2 level
reaches the set point, the damper will be at maximum ventila-
tion and should maintain the set point.
In order to have the CO2 sensor control the economizer
damper in this mannel: first determine the damper voltage out-
put for minimum or base ventilation. Base ventilation is the
ventilation required to remove contaminants during unoccu-
pied periods. The following equation may be used to determine
the percent of outside air entering the building for a given
damper position. For best results there should be at least a
10 degree difference in outside and return-air temperatures.
(To x OA) + (TR x RA) = rim
To = Outdoor-Air Temperature
OA = Percent of Outdoor Air
TR = Return-Air Tempemtme
RA = Percent of Return Air
TM = Mixed-Air Temperature
17

0.22
0.20
,m
,e
,e
.£
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00 0
/
/
/
/
/
/
/
/
/
250 500 750 1000 1250 1500 1750 2000 2250 2500 2750 3000 3250
CFM (Cubic Feet Per Minute)
NOTE: Economizer damper pressure drop is with outdoor air damper totally closed and return air damper fully open.
Fig. 24 -- Pressure Drop for Vertical Economizer
0.34
,e
,e
0.32
0.30 /
0.28
0.26
0.24 /
0.22
0.20
0.18 /
0.16
0.14 /
0.12
0.10 /
0.08 /
0.06
0.04 /
0.02 /
0.00
0 280 800 780 1000 1250 1500 1750 2000 2250 2500 2750 3000 3250
CFM (Cubic Feet Per Minute)
NOTE: Economizer damper pressure drop is with outdoor air damper totally closed and return air damper fully open.
Fig. 25 -- Pressure Drop for Horizontal Economizer
18

Once base ventilation has been determined, set the mini-
mum damper position potentiometer to the correct position.
The same equation can be used to determine the occupied or
maximum ventilation rote to the building. For example, fin output
of 3.6 volts to the actuator provides a base ventilation rate of 5%
and finoutput of 6.7 volts provides file maximum ventilation rate
of 20% (or base plus 15 cfin per pelion). Use Fig. 23 to deter-
mine file maximum setting of the CO2 sensor. For example, a
1100 ppm set point relates to a 15 cfln per pelion design. Use the
1100 ppm curve on Fig. 23 to find the point when file CO2 sensor
output will be 6.7 volts. Line up the point on file graph with file
left side of the chin1 to detemiine that the range configuration for
the CO2 sensor should be 1800 pprn. The EconoMi$er IV con-
troller will output file 6.7 volts from file CO2 sensor to file actua-
tor when the CO2 concentration in the space is at 1100 ppm. The
DCV set point may be left fit 2 volts since the C(_ sensor voltage
will be ignored by the EconoMi$er IV controller until it rises
above the 3.6 volt setting of the minimum position potentiometel:
Once the fully occupied dmnper position has been deter-
mined, set the maximum damper demand control ventilation
potentiometer to this position. Do not set to the maximum
position as this can result in over-ventilation to the space find
potential high humidity levels.
CO2 Sensor Configuration -- The CO2 sensor has preset
standard voltage settings that can be selected anytime after the
sensor is powered up. See Table 4.
Use setting 1 or 2 for Career equipment.
1. Press Clear and Mode buttons. Hold fit least 5 seconds
until the sensor enters the Edit mode.
2. Press Mode twice. The STDSET Menu will appear
3. Use the Up/Down button to select the preset numbel: See
Table 4.
4. Press Enter to lock in the selection.
5. Pless Mode to exit and resume normfd operation.
The custom settings of the CO2 sensor can be changed any-
time after the sensor is energized. Follow the steps below to
change file non-stan&trd settings:
1. Pless Clear and Mode buttons. Hold fit least 5 seconds
until the sensor enters the Edit mode.
2. Pless Mode twice. The STDSET Menu will appem:
3. Use the Up/Down button to toggle to the NONSTD menu
find press Enter.
4. Use the Up/Down button to toggle through each of the
nine variables, starting with Altitude, until the desired set-
ting is reached.
5. Press Mode to move through the variables.
6. Press Enter to lock in the selection, then press Mode to
continue to the next variable.
Dehumidification of Fresh Air with DCV (Demand Con-
trolled Ventilation)Control -- Infomiation fi_om ASHRAE
(American Society of Heating, Refiigeration, and Air Condi-
tioning Engineel_) indicates that the largest humidity load on
any zone is the fiesh air introduced. For some applications, a
device such as a 62AQ energy recovery unit is added to reduce
the moisture content of the fiesh air being brought into the
building when the enthalpy is high. In most cases, the normal
heating and cooling processes are more than adequate to
remove the humidity loads for most commerckfl applications.
This makes the control of the of the dehumidification device
simple when using the enthalpy or differential enthfflpy sensor.
The enthalpy sensor or differentiffl enthalpy sensor is installed
on the equipment to determine economizer operation. The high
enthalpy signal fiom the enthfflpy sensor or differential en-
thalpy sensor can be used to turn on the outdoor air moisture
removal device any time fiesh air is required for the space.
The energy recovery device should be sized for maximum
latent and sensible conditioning fit maximum ventilation on a
design &ty. A calculation for leaving-air temperature on a low
mnbient, low ventilation &ty should fflso be done to detemiine
the mixed-ffir temperature of the return and pre-conditioned
outside ail_ The design should produce an ffir temperature
somewhat near room conditions to prevent reheat of the air
mixture. The energy recovel_y device should be interlocked
with the heat to turn off the device when in the heat mode.
Step 11 -- Install All Accessories --After all of
the factory-installed options have been adjusted, install all
field-instfdled accessories. Refer to the accessory installation
instructions included with each accessory. Consult the Cmrier
Price Pages or RTU (rooftop unit) Building software for acces-
sory package numbers for particular applications.
SETTING
1
2
3
4
5
6
7
8
9
Table 4 -- 002 Sensor Standard Settings
ANALOG
EQUIPMENT OUTPUT
Interface With Standard
Building Control System
Economizer
Health and Safety
Parking/Air Intakes/
Loading Docks
OUTPUT
Proportional
Proportional
Exponential
Proportional
Proportional
Exponential
Exponential
Proportional
Proportional
VENTILATION
RATE
(efm/Pereon)
Any
Any
Any
15
20
15
20
0-10V
4-20 mA
2-10V
7-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
0-10V
4-20 mA
CO2
CONTROLRANGE
(ppm)
0-2000
0-2000
0-2000
0-1100
0- 900
0-1100
0- 900
0-9999
0-2000
OPTIONAL
RELAY SETPOINT
(ppm)
1000
1000
1100
1100
900
1100
900
5000
700
RELAY
HYSTERESIS
(ppm)
50
50
50
50
50
50
50
50O
50
19

PRE-START-UP
F;filure to observe the following warnings could result in
serious personal injuu:
1. Follow recognized safety practices and wear protec-
tive goggles when checking or servicing refiigerant
system.
2. Do not operate compressor or provide any electric
power to unit unless compressor terminal cover is in
place and secured.
3. Do not remove compressor terminal cover until all
electrical sources are disconnected.
4. Relieve all pressure from system before touching or
disturbing anything inside temrinal box if refrigerant
leak is suspected mound compressor terminals.
5. Never attempt to repair soldered connection while re-
frigerant system is under pressure.
6. Do not use torah to remove any component. System
contains oil and refrigerant under pressure. To remove
a component, wear protective goggles and proceed as
follows:
a. Shut off gas to unit and then electrical powel:
b. Reclaim or recover refrigerant to relieve all
pressure from system using both high-pressure
and low-pressure ports.
c. Cut component connection tubing with tubing
cutter and remove component from unit.
d. Carefully unsweat remaining tubing stubs
when necessary. Oil can ignite when exposed
to torch flame.
Proceed as follows to inspect and prepare the unit for initial
st_ut-up:
1. Remove all access panels.
2. Read and follow instructions on all WARNING. CAU-
TION, and INFORMATION labels attached to, or
shipped with, unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages such as
broken lines, loose parts, or disconnected wires, etc.
b. Inspect for oil at all refrigerant tubing connections
and on unit base. Detecting oil generally indicates
a refrigerant leak. Leak-test all refrigerant tubing
connections using electronic leak detector, halide
torch, or liquid-soap solution.
c. Inspect all field-wiring and factory-wiring con-
nections. Be sure that connections are completed
and tight. Be sure that wires are not in contact with
refrigerant tubing or sharp edges.
d. Inspect coil tins. If damaged during shipping and
handling, carefully straighten fins with a fin comb.
4. Verify the following conditions:
a. Make sure that condenser-fan blades are correctly
positioned in fan orifice. See Condenser-Fan
Adjustment section on page 39 for more details.
b. Make sure that air filter(s) is in place.
c. Make sure that condensate drain trap is filled with
water to ensure proper drainage.
d. Make sure that all tools and miscellaneous loose
parts have been removed.
START-UP
Unit Preparation--Make sure that unit has been
installed in accordance with installation instructions and appli-
cable codes.
Gas Piping -- Check gas piping for leaks.
Disconnect gas piping from unit when leak
testing at pressure greater than 1/2 psig. Pres-
sures greater than 1/2 psig will cause gas
valve damage resulting in hazardous condi-
tion. If gas valve is subjected to pressure
greater than I/2 psig, it must be replaced
before use. When pressure testing field-
supplied gas piping at pressures of 1/2 psig
or less, a unit connected to such piping must
be isolated by manually closing the gas
valve.
Return-Air Filters--Make sure correct filters are
inst;dled in unit (see Table 1). Do not operate unit without
return-air filters.
Outdoor-Air Inlet Screens -- Outdoor-air inlet screen
must be in place before operating unit.
Compressor Mounting -- Compressorsare internally
spring mounted. Do not loosen or remove compressor hold-
down bolts.
Crankcase Heaters -- Crankcase heaters ;ue energized
as long as there is power to the unit, the compressor is not oper-
ating, and ambient temperature is below 75 IF.
Internal Wiring--Check all electric_d connections in
unit control boxes. Tighten as required.
Refrigerant Service Ports--Each unit system has
4 Schmder-type service ports: one on the suction line, two on
the liquid line, and one on the compressor dischmge line. Be
sure that caps on the ports are tight.
High Flow Refrigerant Valves -- Three high flow
valves m'e located on the hot gas tube coining out of the com-
pressol: the suction tube going into the compressor, and the
liquid line leaving the condensel: Lmge black plastic caps iden-
tify these valves. These valves have O-rings inside which screw
the cap onto a brass body to prevent leaks. No field access to
these v;dves is available at this time. Ensure the plastic caps re-
main on the v_dves and are tight or the possibility of refrigerant
leakage could occur
Compressor Rotation -- On 3-phaseunits with scroll
compressors, it is important to be cert;fin compressor is rotating
in the proper direction. To determine whether or not comples-
sor is rotating in the proper dilection:
1. Connect service gages to suction and discharge pressure
fittings.
2. Energize the compressor
3. The suction pressure should diop and the discharge pres-
sure should rise, as is normal on any start-up.
If the suction pressure does not drop and the discharge pies-
sure does not rise to normal levels:
1. Note that the evaporator fan (size 006 and 007 only) is
probably also rotating in the wrong direction.
2. Turn off power to the unit and install lockout tag.
3. Reverse any two of the unit power leads.
4. Reenergize to the compressoc Check plessmes.
2O