Carrier 50SZ Series Operation manual

1
50SZ
Single ---Packaged 13 SEER Heat Pump System
1 and 3 Phase --- 2 to 5 Nominal Tons (024---060)
Product Data
C99001
Unit 50SZ
Single--Package Heat Pump for Residential and Light Commercial
Applications
SLow Sound Levels
S13 SEER
FEATURES/BENEFITS
One--piece heat pump with optional electric heater, low installation
cost, dependable performance and easy maintenance.
Efficient operation
High--efficiency design with SEERs (Seasonal Energy Efficiency
Ratios) of 13.0 and HSPFs (Heating Seasonal PerformanceFactors)
of up to 7.7.
Easy Installation
Factory--assembled package is a compact, fully self--contained,
heat pump unit that is pre--wired, pre--piped, and pre--charged for
minimum installation expense. 50SZ units are available in a variety
of standard capacity ranges with voltage options to meet residential
and light commercial requirements. Units install easily on a rooftop
or at ground level.
Durable, dependable components
Scroll compressors are designed for high efficiency. Each com-
pressor is hermetically sealed against contamination to help pro-
mote longer life and dependable operation. Vibration isolation pro-
vides quiet operation. Compressors have internal high--pressure and
overcurrent protection.
Direct--drive multi--speed, PSC (permanent split capacitor)
blower motor is standard on all 50SZ models.
Direct--drive, PSC condenser--fan motors are designed to help re-
duce energy consumption and provide for cooling operation down
to 40_F(4.4_C) outdoor temperature. MotormasterRII low ambi-
ent kit is available as a field--installed accessory and does not require
a special motor.
Corporate thermostats work with Carrier’s small packaged prod-
ucts as a system to promote year round comfort.
Refrigerant system is designed to provide dependability. Liquid
refrigerant strainers are used to promote clean, unrestricted opera-
tion. Each unit leaves the factory with a full refrigerant charge. Re-
frigerant service connections make checking operating pressures
easier.
Low--Pressure/Loss--of--Charge Switch assures added safety and
reliability for the compressor.
Indoor and outdoor coils are computer--designed for optimum
heat transfer and cooling efficiency. The indoor coil is fabricated
from copper tube and aluminum fins and is located inside the unit
for protection against damage. The outdoor coil is internally
mounted on the top tier of the unit. A FIOP (Factory--Installed Op-
tion) metal louvered grille is available on all models. Copper fin
coils and pre--coated fin coils are available from the factory by spe-
cial order. These coils are recommended in applications where alu-
minum fins are likely to be damaged due to corrosion. They are ideal
for seacoast applications.
Low sound ratings ensure aquiet indoor and outdoorenvironment
with sound ratings as low as 72 dBA. (See page 3.)
Easy to service cabinets provide easy single--panel accessibility to
serviceable components during maintenance and installation. The
unit base, with integrated drain, provides easy ground level installa-
tion with or withouta mounting pad.Convenient handholds are pro-
vided to manipulatetheuniton thejob site. A nesting featureensures
a positive unit base to roof curb seal when the unit is roof mounted.
A convenient 3/4--in. wide perimeter flange makes frame mounting
on a rooftop easy.
Downflow operation is easily provided in the field to allow vertical
ductwork connections. The unit base utilizes knockout style seals
on the bottom openings to ensure a positive seal in the horizontal air-
flow mode.
Standard metal duct covers with insulation come with the unit and
cover the duct openings. These can be left in place if the units are
converted to downshot.

2
Cabinets are constructed of heavy duty, phosphated, zinc--coated
prepainted steel capable of withstanding 500 hrs of salt spray. Interi-
or surfaces are insulated with cleanable semi--rigid insulation board,
which keeps the conditioned air from being affected by the outdoor
ambient temperature and provides improved indoor air quality.
(Conforms to American Society of Heating, Refrigeration
and Air Conditioning Engineers No. 62P.) The sloped drain mini-
mizes standing water in the drain, which is provided with an external
drain fitting.
Short--Cycling protection for the compressor is incorporated into
our defrost control board ensuring a five minute delay (+/--2 min-
utes) before restarting compressor after shutdown for any reason.
TABLE OF CONTENTS
PAGE
FEATURES/BENEFITS 1.........................................................................................
MODEL NUMBER NOMENCLATURE 2............................................................................
ARI CAPACITY RATINGS 3......................................................................................
PHYSICAL DATA 4.............................................................................................
ACCESSORIES 5...............................................................................................
DIMENSIONAL DRAWINGS 7--8..................................................................................
SELECTION PROCEDURE 10....................................................................................
PERFORMANCE DATA 11--18....................................................................................
APPLICATION DATA 21.........................................................................................
ELECTRICAL DATA 22.........................................................................................
TYPICAL WIRING SCHEMATICS 23--24...........................................................................
CONTROLS 25.................................................................................................
GUIDE SPECIFICATIONS 26--27..................................................................................
MODEL NUMBER NOMENCLATURE
50SZ 024
Type of Unit
50SZ – Single Pa ckaged
Heat Pump Unit
Electrical Supply
3 – 208/230-1-60
Nominal Cooling Capacity
024 – 2.0 Tons
030 – 2.5 Tons
036 – 3.0 Tons
042 – 3.5 Tons
048 – 4.0 Tons
060 – 5.0 Tons
Options
LEGEND
AL — Aluminum
CU — Copper
---
5 – 208/230-3-60
-- - Wire Grille
AD - Louvered Grille
BT - Wire Grille and vinyl-coated outdoor coil fin
XT - Louvered Grille and vinyl-coated outdoor coil fin
CC - Wire Grille, AL indoor and CU/CU outdoor coil
CU - Wire Grille, Cu/CU indoor and outdoor coils
AC - Louvered Grille, AL indoor and CU/CU outdoor coil
AU - Louvered Grille, CU/CU indoor and outdoor coils
Only used if ordering an option
--
3
N/A
0 1
Series
Packaging
6 – 460-3-60
50SZ

3
ARI* CAPACITIES
COOLING CAPACITIES AND EFFICIENCIES
UNIT 50SZ
(SERIES) NOMINAL TONS STANDARD CFM NET COOLING CAPACITIES (Btuh) SEER† SOUND RATINGS (dB) }
024 2.0 800 24,000 13.0 72
030 2.5 1000 30,000 13.0 72
036 3.0 1200 36,000 13.0 72
042 3.5 1400 41,500 13.0 73
048 4.0 1600 47,000 13.0 78
060 5.0 1750 57,000 13.0 78
HEATING CAPACITIES AND EFFICIENCIES
UNIT 50SZ
(SERIES)
HIGH HEAT CAPACITY
(Btuh) @ 47_F(8.3_C)
HIGH HEAT COP @ 47_F
(8.3_C)
LOW HEAT CAPACITY
(Btuh) @ 17_F(---8.3_C)
LOW HEAT
COP @ 17_F
( --- 8 . 3 _C)
HSPF†
024 23,000 3.3 12,800 2.2 7.7
030 29,000 3.3 16,000 2.2 7.7
036 35,000 3.3 19,200 2.2 7.7
042 41,000 3.3 22,600 2.2 7.7
048 46,000 3.2 25,400 2.2 7.7
060 55,000 3.3 27,600 2.0 7.7
* Air Conditioning & Refrigeration Institute.
{Rated in accordance with U.S. Government DOE Department of
Energy) test procedures and/or ARI Standard 210/240--03.
}Tested in accordance with ARI Standard 270--95 (not listed in ARI).
NOTES:
1. Ratings are net values, reflecting the effects of circulating fan heat.
Ratings are based on:
Cooling Standard: 80_F (26.6_C)db, 67_F (19.4_C)wb indoor
entering--air temperature and 95_F(35_C) db outdoor entering--air
temperature.
2. Before purchasing this appliance, read important energy cost and
efficiency information available from your retailer.
LEGEND
dBA — Sound Levels (decibels)
COP — Coefficient of Performance
HSPF — Heating Season Performance Factor
db —DryBulb
SEER — Seasonal Energy Efficiency Ratio
wb —WetBulb
OUTDOOR SOUND: OCTAVE BAND DATA---DECIBELS (dBA)
UNIT 50SZ
Frequency (Hz) 024 030 036 042 048 060
125 55.9 54.7 57.8 58.4 67.8 64.8
250 57.0 60.0 62.4 63.1 68.9 66.5
500 63.9 66.6 69.5 66.2 71.7 70.4
1000 66.8 67.0 72.3 66.8 72.7 73.2
2000 63.3 63.7 69.0 63.6 69.2 69.6
4000 59.0 59.5 65.4 59.9 65.7 67.1
8000 52.9 52.1 57.4 54.1 58.5 60.6
50SZ

4
PHYSICAL DATA
UNIT SIZE 50SZ 024 030 036 042 048 060
NOMINAL CAPACITY (ton) 22--1/2 33--1/2 4 5
OPERATING WEIGHT (lb.)
(kg)
343
156
366
166
433
196
460
209
480
218
492
223
Compressor Scroll
Refrigerant (R--22) Quantity (lb.) 7.8 8.2 10.7 10.8 12.1 11.8
REFRIGERANT METERING DEVICE AccuRaterr
Orifice ID (in.) 0.065 0.070 0.080 0.088 0.088 0.101
Orifice OD (in.) .032(1).038(1) .035(1).038(1) .038 (2) .046 (2) .052 (2) .057 (2)
CONDENSER COIL
Rows…Fins/in. 2…21 2…21 2…21 2…21 2…21 2…21
Face Area (sq. ft.) 11.9 13.6 15.5 19.4 19.4 19.4
CONDENSER FAN
Nominal Cfm 2700 2700 2800 2800 3300 3300
Diameter 22 22 22 22 22 22
Motor HP (RPM) 1/8 (825) 1/8 (825) 1/8 (825) 1/8 (825) 1/4 (1100) 1/4 (1100)
EVAPORATOR COIL
Rows…Fins/in. 3…17 3…17 3…17 3…17 3…17 4…17
Face Area (sq. ft.) 3.7 3.7 4.7 4.7 5.6 5.6
EVAPORATOR BLOWER
Nominal Airflow (Cfm) 800 1000 1200 1400 1600 1750
Size (in.)
(mm)
10x10
254x254
10x10
254x254
11x10
279x254
11x10
279x254
11x10
279x254
11x10
279x254
Motor HP (RPM) 1/3 (1050) 1/3 (1050) 1/2 (1000) 1/2 (1075) 1/2 (1075) 1 (1040)
Return--Air Filters (in.)* Throwaway 20x24x1 20x24x1 24x36x1 24x36x1 24x36x1 24x36x1
Return--Air Filters (mm)* Throwaway 208x610x25 208x610x25 610x914x25 610x914x25 610x914x25 610x914x25
REGISTERED
ISO 9001:2000
ELECTRIC HEAT PRESSURE DROP TABLES (w.c)
Small Cabinet: 024--030
STATIC CFM
500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600
5kW 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.06 0.07
10 kW 0.00 0.00 0.00 0.00 0.00 0.02 0.04 0.06 0.07 0.09 0.10 0.11
15 kW 0.00 0.00 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18
20 kW 0.00 0.00 0.02 0.04 0.06 0.08 0.09 0.11 0.13 0.15 0.17 0.19
Large Cabinet: 036--060
STATIC CFM
1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 2400 2500
5kW 0.00 0.00 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12
10 kW 0.00 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13
15 kW 0.00 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15
20 kW 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 0.16
50SZ

5
OPTIONS AND ACCESSORIES
Factory--installed options
Louvered grille provides hail and vandalism protection. A wire
grille is standard on all models. See model number nomenclature for
louvered grille options.
Coil options include copper/copper and vinyl--coated construction
for refrigerant coils. Units are shipped standard with copper tube/
aluminum fin construction. See model number nomenclature for
coil options.
Field--installed accessories
Economizer with Solid--State Controls and Barometric
Relief Dampers
Manual Air Damper (25% open)
Electric Heaters
Filter Rack
Flat Roof Curbs (8--in. and 14--in.)
Square--to--Round Duct Transition Kit
Thermostats
Controls Upgrade Kit
Crankcase Heater
Rigging Kit
Low Ambient Kit (Motormaster®II Control)
Solid--State Time Guard®II Device
Compressor Hard Start Kit
Economizer with solid--state controls and barometric relief
dampers includes filter racks and provides outdoor air during cool-
ing and reduces compressor operation.
Manual outside air damper includes hood and filter rack with ad-
justable damper blade for up to 25% outdoor air.
Electric heaters provide additional heat in the unit when required.
Each package has a heater module that slides into the controls
compartment. Heater sizes range from 5.0 to 20.0 kW. The electric
heater design allows the use of a single--point power supply for the
entire unit, resulting in lower installed costs.
Flat roof curbs in both 8 in. and 14 in. sizes are available for roof
mounted applications.
Square--to--round duct transition kit enables 024--048 size units
to be fitted to 14 in. round ductwork.
Thermostats provide control for the system heating and cooling
functions. Thermostat models are available in both programmable
and non--programmable versions.
Controls upgrade kit supplies high and low pressure safety protec-
tion and protects the unit from operating in unsuitable conditions.
Crankcase heater provides anti--floodback protection for low--
load cooling applications.
Rigging kit includeslifting bracketswhich are inserted into theunit
base rigging holds to lift unit for rooftop applications.
Low--ambient kit (Motormaster II control) allows the use of me-
chanical cooling down to outdoor temperatures as low as 0_F
(--17.7_C).
Filter rack features easy installation, serviceability, and high--fil-
tering performance for vertical and horizontal applications.
Compressor hard start kit gives a boost to the compressor motor
at each start--up.
ELECTRIC HEATERS
ODS CATALOG
ORDERING NO.
NOMINAL
CAPACITY (kW) FUSES USED WITH SIZES
024 030 036 042 048 060
ELECTRIC HEATERS (208/230 — SINGLE PHASE — 60 Hz)
CPHEATER052A00 5.0 0 X X X X X
CPHEATER064A00 5.0 4 X
CPHEATER070A00 7.2 4 X X X X
CPHEATER050A00 10.0 4 X X X X X X
CPHEATER066A00 15.0 6 X X X X X
CPHEATER054A00 20.0 6 X X X
ELECTRIC HEATERS (208/230 — THREE PHASE — 60 Hz)
CPHEATER055A00 5.0 0 X X X X X
CPHEATER056A00 10.0 0 X X X X
CPHEATER068A00 10.0 6 X
CPHEATER057A00 15.0 0 X
CPHEATER058A00 15.0 6 X X X X
CPHEATER059A00 20.0 6 X X X
ELECTRIC HEATERS (460 — THREE PHASE — 60 Hz)
CPHEATER060A00 5.0 0 X X X X
CPHEATER061A00 10.0 0 X X X X
CPHEATER062A00 15.0 0 X X X X
CPHEATER063A00 20.0 0 X X X
NOTE: Electric heaters are rated at 240v and 480v. Refer to Multiplication Factors table for other voltages.
LEGEND
ODS⎯Order Distribution System
Minimum Airflow for Reliable Electric Heater Operation (cfm)
UNIT--50SZ 024 030 036 042 048 060
AIRFLOW 800 1000 1200 1400 1600 2000
50SZ

6
ECONOMIZER
COIL
FILTER
SIDE VIEW
CAULK BOTTOM CORNER
OF ECONOMIZER
ON EACH SIDE
BASE
COIL
FLANGE
ON BASE
DETAIL
ECONOMIZER
FI LTER
FILTER ACCESS DOOR
(HORIZONTAL
APPLICATION ONLY.)
DO NOT REMOVE
FROM DOWNFLOW
DISCHARGE.
REPLACEMENT
PANEL
HOLE FOR
ECONOMIZER
WIRING HARDNESS
DOOR
LATCH ANGLE
HINGED FILTER
ACCESS DOOR INSTALL
FILTER ACCESS
DOOR STICKER
ALUMINUM
FILTER
RAINHOOD
11 13/32”
17 13/32
16 1/4”
EV APORATOR
COIL
TOP FILTER RACK
BEND FLANGE AT 90˚-SCREW TO
DIVIDER WITH 1-IN. SCREW
BOTTOM FILTER
RACK
DAMPER
BLADE
MANUAL OUTSIDE
AIR HOOD
REPLACEMENT
PANEL
ECONOMIZER
FILTER RACK MANUAL OUTSIDE AIR DAMPER
A05239
50SZ

7
BASE UNIT DIMENSIONS⎯50SZ024--030
REQUIRED CLEARANCE FOR OPERATION AND SERVICING
INCHES [mm]
EVAP. COIL ACCESS SIDE............................................................36.00 [914.0]
POWER ENTRY SIDE....................................................................42.00 [1066.8]
(EXCEPT FOR NEC REQUIREMENTS)
UNIT TOP .......................................................................................48.00 [1219.2]
SIDE OPPOSITE DUCTS ..............................................................36.00 [914.0]
DUCT PANEL .................................................................................12.00 [304.8] *
*MINIMUM DISTANCES: IF UNIT IS PLACED LESS THAN 304.8 [12.00] FROM
WALL SYSTEM, THEN SYSTEM PERFORMANCE MAYBE COMPROMISE.
R
EQUIRED CLEARANCE TO COMBUSTIBLE MATL.
INCHES [mm]
TOP OF UNIT...................................................................................14.00 [355.6]
DUCT SIDE OF UNIT.........................................................................2.00 [50.8]
SIDE OPPOSITE DUCTS ................................................................14.00 [355.6]
BOTTOM OF UNIT .............................................................................0.50 [12.7]
N
EC. REQUIRED CLEARANCES.
INCHES [mm]
BETWEEN UNITS, POWER ENTRY SIDE ....................................42.00 [1066.8]
UNIT AND UNGROUNDED SURFACES, POWER ENTRY SIDE .36.00 [914.0]
UNIT AND BLOCK OR CONCRETE WALLS AND OTHER
GROUNDED SURFACES, POWER ENTRY SIDE.........................42.00 [1066.8]
(
Refer to Maximum Operating Clearances)
A05162
UNIT ELECTRICAL
CHARACTERISTICS
UNIT WEIGHT UNIT HEIGHT
IN. [MM]
“A”
CENTER OF GRAVITY
IN. [MM]
lb kg X Y Z
50SZ024 208/230--1--60 343 156 39.02 [991] 20.0 [508] 19.3 [490] 17.6 [447]
50SZ030 208/230--1--60, 208/230--3--60 366 166 41.02 [1042] 20.0 [508] 14.0 [356] 13.0 [330]
50SZ

8
BASE UNIT DIMENSIONS⎯50SZ036--060
REQUIRED CLEARANCE FOR OPERATION AND SERVICING
INCHES [mm]
EVAP. COIL ACCESS SIDE............................................................36.00 [914.0]
POWER ENTRY SIDE....................................................................42.00 [1066.8]
(EXCEPT FOR NEC REQUIREMENTS)
UNIT TOP .......................................................................................48.00 [1219.2]
SIDE OPPOSITE DUCTS ..............................................................36.00 [914.0]
DUCT PANEL .................................................................................12.00 [304.8] *
*MINIMUM DISTANCES: IF UNIT IS PLACED LESS THAN 304.8 [12.00] FROM
WALL SYSTEM, THEN SYSTEM PERFORMANCE MAYBE COMPROMISE.
R
EQUIRED CLEARANCE TO COMBUSTIBLE MATL.
INCHES [mm]
TOP OF UNIT...................................................................................14.00 [355.6]
DUCT SIDE OF UNIT.........................................................................2.00 [50.8]
SIDE OPPOSITE DUCTS ................................................................14.00 [355.6]
BOTTOM OF UNIT .............................................................................0.50 [12.7]
N
EC. REQUIRED CLEARANCES.
INCHES [mm]
BETWEEN UNITS, POWER ENTRY SIDE ....................................42.00 [1066.8]
UNIT AND UNGROUNDED SURFACES, POWER ENTRY SIDE .36.00 [914.0]
UNIT AND BLOCK OR CONCRETE WALLS AND OTHER
GROUNDED SURFACES, POWER ENTRY SIDE.........................42.00 [1066.8]
(
Refer to Maximum Operating Clearances)
A05126
UNIT ELECTRICAL
CHARACTERISTICS
UNIT WEIGHT UNIT HEIGHT
IN. [MM]
“A”
CENTER OF GRAVITY
IN. [MM]
lb kg X Y Z
50SZ036 208/230--1--60, 208/230--3--60, 460--3--60 433 196 42.98 [1092] 21.0 [533] 20.5 [520] 16.6 [422]
50SZ042 208/230--1--60, 208/230--3--60, 460--3--60 460 209 46.98 [1193] 21.0 [533] 20.5 [520] 17.1 [434]
50SZ048 208/230--1--60, 208/230--3--60, 460--3--60 480 218 46.98 [1193] 21.0 [533] 20.0 [508] 17.4 [442]
50SZ060 208/230--1--60, 208/230--3--60, 460--3--60 492 223 46.98 [1193] 21.0 [533] 20.0 [508] 17.6 [447]
50SZ

9
ACCESSORY DIMENSIONS
Gasket around
outer edge
Insulated
deck pan
Gasket around
duct
S/A
R/A
HVACunit
base
*Gasketing
outer flange
Flashing field
supplied
Roofing material
field supplied
Cant strip
field supplied
*Provided with roof curb
Roof
Ductwork
field supplied
Insulation(field
supplied)
Roof curb*
Wood nailer*
Gasketing
inner flange*
Screw
(NOTE A)
Roof Curb for Small Cabinet
Note A: When unit mounting screw is used,
retainer bracket must also be used.
HVAC unit
base
*Gasketing
outer flange
Flashing field
supplied
Roofing material
field supplied
Cant strip
field supplied
*Provided with roof curb
Roof
Ductwork
field supplied
Insulation(field
supplied)
Roof curb*
Wood nailer*
Gask eting
inner flange*
Screw
(NOTE A)
Roof Curb for Large Cabinet
Note A: When unit mounting screw is used,
retainer bracket must also be used.
A
BTyp.
Supply opening
(B x C)
Long
Support
D
F
Return opening
(B X C)
Insulated
deck pan
Short
Support
CTyp.
G
E
F
G
D
E
A05308
UNIT SIZE ODS CATALOG
NUMBER
A
IN. (MM)
B
IN. (MM)
C
IN. (MM)
D
IN. (MM)
E
IN. (MM)
F
IN. (MM)
G
IN. (MM)
50SZ024--030 CPRFCURB006A00 8 (203) 11 (279) 16--1/2 (419) 28--3/4 (730) 30--3/8 (771) 44--5/16 (1126) 45--15/16 (1167)
CPRFCURB007A00 14 (356) 11 (279) 16--1/2 (419) 28--3/4 (730) 30--3/8 (771) 44--5/16 (1126) 45--15/16 (1167)
50SZ036--060 CPRFCURB008A00 8 (203) 16--3/16 (411) 17--3/8 (441) 40--1/4 (1022) 41--15/16 (1065) 44--7/16 (1129) 46--1/16 (1169)
CPRFCURB009A00 14 (356) 16--3/16 (411) 17--3/8 (441) 40--1/4 (1022) 41--15/16 (1065) 44--7/16 (1129) 46--1/16 (1169)
NOTES:
1. Roof curb must be set up for unit being installed.
2. Seal strip must be applied, as required, to unit being installed.
3. Dimensions are in inches.
4. Dimension in ( ) are in millimeters.
5. Roof curb is made of 16--gauge steel.
6. Attach ductwork to curb (flanges of duct rest on curb).
7. Insulated panels: 1--in. thick fiberglass 1 lb. density.
8. When unit mounting screw is used (see Note A), a retainer bracket must be used as well. This bracket must also be used when required by code for hurricaneorseismic
conditions. This bracket is available through Micrometl.
50SZ

10
50SZ CORNER WEIGHTS AND SUGGESTED RIGGING
x
y
12
3
4
C00071
DETAIL A
A05161
CORNER WEIGHTS (SMALL CABINET) Lbs. CORNER WEIGHTS (LARGE CABINET) Lbs.
Unit 024 030 Unit 036 042 048 060
Total Weight 343 366 Total Weight 433 460 480 492
Corner Weight 1 69 74 Corner Weight 1 87 93 97 99
Corner Weight 2 53 57 Corner Weight 2 68 72 74 76
Corner Weight 3 83 88 Corner Weight 3 104 111 116 119
Corner Weight 4 138 147 Corner Weight 4 174 184 193 198
Rigging Weight 353 376 Rigging Weight 443 470 490 502
Shipping Weight 373 396 Shipping Weight 463 490 510 522
SELECTION PROCEDURE (WITH EXAMPLE)
I. Determine cooling and heating requirements of design condi-
tions:
Given:
Required Cooling Capacity (TC) 28,000 Btuh..............
Sensible Heat Capacity (SHC) 20,500 Btuh................
Required Heating Capacity (SHC) 28,550 Btuh.............
Outdoor Entering Air Temperature 95°F(35°C).............
Outdoor--Air Winter Design Temperature 20°F(--6.6°C).......
Indoor--Air Winter Design Temperature 70°F (21.1°C)........
Indoor Entering--Air Temperature 80°F (26.6°C).............
67°F (19.4°C) ewb
Indoor--Air Quantity 1125 cfm..........................
External Static Pressure 0.20 in. wc.......................
Electrical Characteristics (V--Ph--Hz) 230--1--60.............
edb ⎯entering dry bulb
ewb ⎯entering wet bulb
II. Select unit based on required cooling capacity.
Enter Cooling Extended Performance table at outdoor entering--air
temperature of 95_F(35°C), indoor air entering at 1125 cfm and
67_F (19.4°C) ewb (entering wet bulb). Theunit will provide atotal
cooling capacity of 30,900 Btuh and a sensible heat capacity of
24,800 Btuh.
For indoor--air temperature other than 80_F (26.6°C) edb (entering
dry bulb), calculate sensible heat capacity correction, as required,
using the formula found in Note 3 following the cooling capacities
tables. NOTE: Unit ratings are net capacities.
III. Select electric heat.
Enter the unit Heating Extended Performance table at 1125 cfm. At
70_F (21.1°C) return indoorair and 20_F(--6.6°C) air entering out-
door coil, the integrated heating capacity is 16,200 Btuh. (Select in-
tegrated heating capacity value since deductions for outdoor--coil
frost and defrost have already been made. No correction is required.)
The required heating capacity is 28,550 Btuh. Therefore, 12,350
Btuh (28,550 -- 16,200) additional electric heat is required.
Determine additional electric heat capacity in kW.
12,350 Btuh = 3.6 kW of heat required
3,414 Btuh/kW
Enter the Electric Heater table on page 5 for 208/230 v, single--
phase,unit. The5--kW heater at 240 v most closely satisfies theheat-
ing required. To calculate kW at 230 v, multiply the heater kW by
multiplication factor 0.92 found in the Multiplication Factors table
on page 17.
5 kW x 0.92 = 4.6 kW
4.6 kW x 3414 = 15,704 Btuh
Total unit heating capacity is 31,900 Btuh (16,200 + 15,704).
IV. Determine fan speed and power requirements at design condi-
tions.
Before entering the air delivery tables, calculate the total static pres-
sure required.
50SZ