Unitary products group HF-25 - 25 Ton, HL-30 - 30 Ton, HL-50 - 50 Ton, HL-40 - 40 Ton Installation Manual

INSTALLATION MANUAL
CONTENTS
GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . 5
AGENCY APPROVALS . . . . . . . . . . . . . . . . . . . . . . . . . 5
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
OPERATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
SPLIT-SYSTEM
CONDENSING UNITS
(AIR COOLED)
MODELS: HF-25 - 25 Ton
HL-30 - 30 Ton HL-40 - 40 Ton HL-50 - 50 Ton
NOTES, CAUTIONS AND WARNINGS
Installer should pay particular attention to the words: NOTE, CAUTION, and WARNING. Notes clarify or make the installation easier. Cautions to prevent equipment damage. Warnings alert installer that personal injury and/or equipment dam­age may result if installation procedure is not handled properly.
CAUTION: READ ALL SAFETY GUIDES BEFORE
YOU BEGIN TO INSTALL UNIT.
SAVE THIS MANUAL
are intended to
are given
are given to
278806-BIM-A-1106
TABLE OF CONTENTS
278806-BIM-A-1106
NOMENCLATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . .5
REFERENCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
AGENCY APPROVALS . . . . . . . . . . . . . . . . . . . . . . . . . . .5
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
ROOFTOP LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
GROUND LEVEL LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . .7
CLEARANCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
RIGGING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
POWER WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
PHASING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
CONTROL WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
COMPRESSOR CRANKCASE HEATERS . . . . . . . . . . . .9
REFRIGERANT MAINS . . . . . . . . . . . . . . . . . . . . . . . . .10
LINE SIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
SERVICE VALVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
EVACUATION AND CHARGING . . . . . . . . . . . . . . . . . .12
PIPING AND ELECTRICAL CONNECTIONS . . . . . . . . .18
PIPING AND ELECTRICAL CONNECTION SIZES . . . .20
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
CRANKCASE HEATER . . . . . . . . . . . . . . . . . . . . . . . . .22
PRE-START CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . .22
INITIAL START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
SEQUENCE OF OPERATION . . . . . . . . . . . . . . . . . . . .22
OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
SAFETY CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
PUMP OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
CONTINUOUS BLOWER . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
INTERMITTENT BLOWER . . . . . . . . . . . . . . . . . . . . . . . . . . .23
COOLING SEQUENCE OF OPERATION . . . . . . . . . . . . . . . .24
FLASH CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
UNIT CONTROL BOARD OPTION SETUP . . . . . . . . . .26
OPTION BYTE SETUP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
CONDENSER FAN OPERATION . . . . . . . . . . . . . . . . . .26
OPERATION WITH A TWO-STAGE THERMOSTAT . . .26 OPERATION WITH A FOUR-STAGE THERMOSTAT . .26
SECURE OWNER'S APPROVAL . . . . . . . . . . . . . . . . . .26
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
CLEANING CONDENSER SURFACE . . . . . . . . . . . . . .27
LUBRICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
COMPRESSOR REPLACEMENT . . . . . . . . . . . . . . . . .27
LIST OF FIGURES
Fig. # Pg. #
1 CORNER WEIGHTS & CENTER OF GRAVITY . . . . . 7
2 TYPICAL RIGGING . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 TYPICAL FIELD WIRING DIAGRAM - HF-25 UNIT . 15 4 TYPICAL FIELD WIRING DIAGRAM - HL-30, 40, 50
UNITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5 TYPICAL LIQUID LINE SOLENOID WIRING . . . . . . 17
6 HF/HL UNIT DIMENSIONS . . . . . . . . . . . . . . . . . . . . 18
7 25, 30 & 40 TON POWER AND CONTROL WIRING
CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8 50 TON POWER AND CONTROL WIRING
CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
9 25 TON PIPING CONNECTIONS . . . . . . . . . . . . . . . 20
10 30 & 40 TON PIPING CONNECTIONS . . . . . . . . . . . 21
11 50 TON PIPING CONNECTIONS . . . . . . . . . . . . . . . 21
12 UNIT CONTROL BOARD . . . . . . . . . . . . . . . . . . . . . . 25
13 FAN ORIENTATION CONTROL BOX END . . . . . . . . 26
14 25 TON CHARGING CHART . . . . . . . . . . . . . . . . . . . 27
15 30 TON CHARGING CHART . . . . . . . . . . . . . . . . . . . 28
16 40 TON CHARGING CHART . . . . . . . . . . . . . . . . . . . 28
17 50 TON CHARGING CHART . . . . . . . . . . . . . . . . . . . 29
18 TYPICAL 25 TON CONDENSER UNIT WIRING
DIAGRAM - 208/230-3-60 . . . . . . . . . . . . . . . . . . . . . 30
19 TYPICAL 25 TON CONDENSER UNIT WIRING
DIAGRAM - 460-3-60, 575-3-60 . . . . . . . . . . . . . . . . . 31
20 TYPICAL 30 OR 40 TON CONDENSING UNIT WIRING
DIAGRAM - 208/230-3-60 . . . . . . . . . . . . . . . . . . . . . 32
21 TYPICAL 30 OR 40 TON CONDENSING UNIT WIRING
DIAGRAM - 460-3-60, 575-3-60 . . . . . . . . . . . . . . . . . 33
22 TYPICAL 50 TON CONDENSER UNIT WIRING
DIAGRAM - 208/230-3-60 . . . . . . . . . . . . . . . . . . . . . 34
23 TYPICAL 50 TON CONDENSER UNIT WIRING
DIAGRAM - 460-3-60, 575-3-60 . . . . . . . . . . . . . . . . . 35
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TABLE OF CONTENTS - Con’t.
LIST OF TABLES
Tbl. # Pg. #
1 PHYSICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 UNIT APPLICATION DATA . . . . . . . . . . . . . . . . . . . . . 6
3 CORNER WEIGHTS & CENTER OF GRAVITY
(INCHES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 MINIMUM CLEARANCES . . . . . . . . . . . . . . . . . . . . . . 8
5 ELECTRICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 SUCTION LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
7 LIQUID LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8 R-22 LINE CHARGE . . . . . . . . . . . . . . . . . . . . . . . . . 14
Tbl. #
9 UNIT DIMENSIONS (INCHES) . . . . . . . . . . . . . . . . . 18
10 PIPING AND ELECTRICAL CONNECTION SIZES
(25T) (INCHES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
11 PIPING AND ELECTRICAL CONNECTION SIZES
(30/40/50T) (INCHES) . . . . . . . . . . . . . . . . . . . . . . . . 20
12 ELECTRICAL POWER KNOCKOUT
SIZES (INCHES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
13 UNIT CONTROL BOARD FLASH CODES . . . . . . . . 25
Pg. #
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NOMENCLATURE
PRODUCT NOMENCLATURE
OUTDOOR SPLIT CONDENSING UNITS
H
F -30 C 00 A T A AA 2
278806-BIM-A-1106
Model #
Model Number Description
Options
H Product Category H = Air Conditioner Split System
L Product Identifier
Nominal Cooling
-30
Capacity MBH
F = R-22 Stan dard Efficiency 2-Pipe L = R-22 Standard Efficiency 4-Pipe
-25 = 25 Ton
-30 = 30 Ton
-40 = 40 Ton
-50 = 50 Ton
CHeat Type C = Cooling Only
Nominal Heating
00
Capacity
00 = No Heat Installed
A Airflow Options A = St andard Motor
TVoltage
A Installation Options
AA Additional Options
T = 208/230-3-60 W = 460-3-60
A = None B = Disconnect
AA = None AC = Technicoated Coil
X = 575-3-60
C = Service Valves D = Service Valves + Disconnect
2 Product Generation 1 = 1st Generation 2 = 2nd Generation
NOTE: HL models are designed for 4-Pipe (dual)
applications only . 4- Pipe condensing unit s can­not be matched with one single 2-Pipe air han­dler.
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GENERAL
These condensing units are designed for outdoor installation on a roof or at ground level. Every unit is completely piped and wired at the factory and is shipped ready for immediate installation. Only the liq­uid and suction lines to the evaporator coil, the filter drier, the control wiring and the main power wiring are required to complete the installation. Each unit is dehy­drated, evacuated, leak tested and pressure tested at 450 psig before being pressurized with a holding charge of refrigerant-22 for shipment and/or storage.
All controls are located in the front of the unit and are readily accessible for maintenance, adjustment and service. All wiring (power and control) can be made through the front of the unit.
SAFETY CONSIDERATIONS
Installer should pay particular attention to the words: NOTE, CAUTION, and WARNING. Notes to clarify or make the installation easier. Cautions given to prevent equipment damage. Warnings given to alert installer that personal injury and/or equip­ment damage may result if installation procedure is not handled properly.
are intended
are
are
This product must be installed in strict compli­ance with the enclosed installation instructions and any applicable local, state, and national codes including but not limited to, building, electrical and mechanical codes.
REFERENCE
This instruction covers the installation and operation of the basic condensing unit. For information on the installation and operation of the evaporator blower units, refer to instruction Form No. 035-18496-000.
All accessories come with a separate Installation Man­ual.
Refer to Parts Manual for complete listing of replace­ment parts on this equipment.
AGENCY APPROVALS
Design certified by ETL as follows:
Improper installation may create a condition
where the operation of the product could cause
personal injury or property damage.
Improper installation, adjustment, alteration,
service or maintenance can cause injury or
property damage. Refer to this manual for
assistance or additional information, consult a
qualified installer or service agency.
1. For use as a cooling unit.
2. For outdoor installation only.
INSPECTION
As soon as a unit is received, it should be inspected for possible damage during transit. If damage is evident, the extent of the damage should be noted on the car­rier’s freight bill. A separate request for inspection by the carrier’s agent should be made in writing.
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TABLE 1: PHYSICAL DATA
278806-BIM-A-1106
Compressor
Model
HF/HL
System 1 15 2 2 24 36 12690 1.25 25 60 1730 1790 30.08 1.0
System 2 15 2 2 24 36 12690 1.25 25 60 30.08
System 1 20 2 2 30 22 15414 1.50 32.5 78 1961 2037 37.83 1.0
System 2 20 2 2 30 22 15414 1.50 32.5 78 37.83
System 1 25 2 2 30 26 19386 1.50 52 78 2470 2563 46.59 1.0
System 2 25 2 2 30 26 19386 1.50 52 78 46.59
Nominal
Capacity
(tons)
-25 25 2 4 24 34 23244
-30
-40
-50
1.
All compressors are Copeland Scrolls.
2.
One of the fan motors is controlled by a pressure switch and will not operate until system pressure reaches 280 psig and drops below 180 psig.
3.
The total operating charge of the condensing unit, matching indoor unit and 25 feet of interconnecting piping.
1
Capacity
Stages
Fan (Propeller) Fan Motor Coil (Copper Tube-Aluminum Fin)
Pitch
Qty. Dia.
Deg.
Nom.
CFM
Condenser
RPM HP
1.25 50
1140
Face Area
(Ft.
Rows Deep
2
)
2
Width
(In.)
60
OD
inch
(In.)
3/8 16
Fins
Tube
Coil
Unit Weight
(Lbs.)
Ship-
per
Opera-
ping
1608 1658 49.65 1.0
tion
Operation
(Lbs.-Oz.)
Charge, R-22
3
Holding
(Lbs.)
TABLE 2: UNIT APPLICATION DATA
208/230-3-60 187/252
Voltage Variation
Min. / Max.
Ambient Air on Condenser Coil
Suction Pressure at Compressor and
Corresponding Temp. at Saturation
1.
Utilization range “A” in accordance with ARI Standard
110.
2.
These units can operate in an ambient temperature of 125°F providing the wet bulb temperature of the air entering the evaporator coil does not exceed 67°F . Unit can operate to 0°F if equipped with a low ambient kit.
1
Min. /Max.
Min. / Max.
460-3-60 432/504 575-3-60 540/630
57.5 psig / 92.6 psig
40°F/125°F
2
32.0 ºF / 55.0 ºF
INSTALLATION
LIMITATIONS
These units must be installed in accordance with all national and local safety codes. If no local codes apply, installation must conform to the appropriate national codes. Units are designed to meet National Safety Code Standards. If components are to be added to a unit to meet local codes, they are to be installed at the dealer's and/or the customer's expense.
LOCATION
Use the following guidelines to select a suitable loca­tion for both the condensing unit and the evaporator.
1. The condensing unit is designed for outdoor instal­lation only.
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2. The condenser fans are the propeller type and are not suitable for use with ductwork in the condenser air stream.
3. The condensing unit and the evaporator should be positioned to minimize the number of bends in the refrigerant piping.
4. The condensing unit should be as close to the evaporator as practical.
5. The condensing unit should not be installed where normal operating sounds may be objectionable.
6. The evaporator should be located within the build­ing, either outside or inside the conditioned space.
ROOFTOP LOCATIONS
Be careful not to damage the roof. Consult the building contractor or architect if the roof is bonded. Choose a location with adequate structural strength to support the unit.
The condensing unit must be mounted on level sup­ports. The supports can be channel iron beams or wooden beams treated to reduce deterioration.
Minimums of two (2) beams are required to support each unit. The beams should: (1) be positioned per­pendicular to the roof joists. (2) Extend beyond the dimensions of the section to distribute the load on the roof. (3) Be capable of adequately supporting the con­centrated loads at the corners. See Figure 1.
These beams can usually be set directly on the roof. Flashing is not required.
NOTE: On bonded roofs, check for special installation
requirements.
GROUND LEVEL LOCATIONS
It is important that the units be installed on a substan­tial base that will not settle, causing strain on the refrig­erant lines and possible leaks. A one-piece concrete slab with footers that extend below the frost line is rec­ommended. The slab should not be tied to the building foundation, as noise will telegraph.
TABLE 3: CORNER WEIGHTS & CENTER OF GRAVITY (INCHES)
Unit Model
HF-25 1608 1658 110.46 88.46 337 412 472 386 49.7 47.7 723.5 884.5 HL-30 1730 1790 110.46 88.46 363 531 497 339 44.8 42.8 701.6 1028.4 HL-40 1961 2037 128.46 88.46 393 598 585 385 51.0 43.8 778.5 1182.5 HL-50 2470 2563 128.46 88.46 470 757 767 476 49.2 44.5 946.0 1524.0
Unit Weight (Lbs.)
Shipping Operation Length Width
Unit Dimensions
(Inches)
A B C D Dim X Dim Y
Weight
A to D
Weight
B to C
FIGURE 1 - CORNER WEIGHTS & CENTER OF GRAVITY
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Concrete piers can also support ground level units. These piers should (1) extend below the frost line, (2) be located under each of the section's four corners, and (3) be sized to carry the load of the corner it sup­ports.
On either rooftop or ground level installations, rubber padding can be applied under the unit to lessen any transmission of vibration.
Holes are provided in the bas e rails for bolting the unit to its foundation.
For ground level installations, precautions should be taken to protect the unit from tampering and unautho­rized persons from injury. Screws on access panels will prevent casual tampering. Further safety precautions such as a fenced enclosure or locking devices on the panels may be advisable. Check local authorities for safety regulations.
Do not permit overhanging structures or shrubs to obstruct condenser air discharge.
RIGGING
Exercise care when moving the unit. Do not remove any crating until the unit is near the place of installation.
Spreaders, longer than the largest dimension across the unit must be used across the top of the unit.
Before lifting a unit, make sure that its weight is distributed equally on the cables so that it will lift evenly.
When preparing to move the unit, always determine the center of gravity (see Table 3 and Figure 1) of the unit in order to equally distribute the weight. Slings con­nected to the compressor end of a unit will usually have to be made shorter, so the unit will lift evenly (see Figure 2).
CLEARANCES
The units must be installed with sufficient clearance for air to enter the condenser coil, for air discharge and for servicing access. See Table 4 for clearances.
NOTE: Additional clearance is required to remove the
compressors out the side of the unit, unless a means is available to lift the compressor out through the top of the unit.
TABLE 4: MINIMUM CLEARANCES
Clearance Description Distance in Inches
Overhead (Top) 120
Front (Access Cover) 36
Rear (piping connections) 36
Left Side 30
Right Side 30
1
Bottom
1.
In all installations where snow accumula tes and winter operation is expected, additi onal height must be provided to insure normal condenser airflow.
0
FIGURE 2 - TYPICAL RIGGING
Rig units by attaching chain or cable hooks to the holes provided on the base rail. See Figure 7 for details on rigging holes.
The length of the spreader bars must exceed the width of the unit. Refer to Table 3 for unit weights.
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NOTE: If planning to handle the 25-50 ton split with a
fork truck, 1WS0407 skid for HF-25/ HL-30 a nd 1WS0408 skid for HL-40/-50 units will be required.
If handling a unit equipped with a 1WS skid, length of forks must be a minimum of 96”. Fork lengths less than 96” will not span the required width of the skid and can cause damage to the unit’s base rails or condenser coils.
POWER WIRING
Check the available power and the unit n ameplate for like voltage. Run the necessary number of properly sized wires to the unit. Provide a disconnect switch (if not included with the unit) and fusing as required. Route the conduit through the large knockout located on the front of the electrical box. See Table 5 for Elec­trical Data.
The disconnect switch may be bolted to the side of the unit but not to any of the removable panels; this would interfere with access to the unit. Make sure that no refrigerant lines will be punctured when mounting the disconnect switch, and note th at it must be suitable for outdoor installation.
rotate in the wrong direction at start- up, the electrical connection to the unit is misphased. Change the incoming line connection phasing to obtain proper rota­tion. (Scroll compressors operate in only one direction. If the scroll is drawing low amperage, has similar suc­tion and discharge pressures, or producing a high noise level, the scroll is misphased.)
Scroll compressors require proper rotation to operate correctly. Units are properly phased at the factory. Do not change the internal wiring to make the blower condenser fans or compres­sor rotate correctly.
CONTROL WIRING
Route the necessary low voltage con tr ol wires from the Simplicity™ control board to the thermostat and also from the low voltage condensing section control box or the terminal block inside the evapor ator unit and to the evaporator fan motor controller. Refer to Figures 3 and 4 for field wiring diagrams. A terminal block is provided in the evaporator control box to accommodate the wir­ing from the evaporator solenoid valves.
COMPRESSOR CRANKCASE HEATERS
All power and control wiring must be in accor­dance with National and Local electrical codes.
START-UP
PHASING
The units are properly phased at the factory. Check for proper compressor rotation. If the fans or compressors
The compressors are equipped with crankcase heaters to prevent the migration of refrigerant to the compres­sors. The heaters are energized only when the unit is not running.
If the main switch is disconnected for long periods of shut down, do not attempt to start the unit for 8 hours after the switch has been re-connected. This will allow sufficient time for all liquid refrigerant to be driven out of the compressor.
Unitary Products Group 9
TABLE 5: ELECTRICAL DATA
Unit Model
Designation
HF-25
HL-30
HL-40
HL-50
Power Supply Qty.
2 208/230-3-60 2 47.1 350.0 208/230-3-60 1.25 4 4.5/4.3 124.6 150 150 4 460-3-60 2 25.0 158.0 460-3-60 1.25 4 2.15 64.9 80 70 5 575-3-60 2 19.9 125.0 575-3-60 1.25 4 1.7 51.9 70 60 2 208/230-3-60 4 32.1 195.0 208/230-3-60 1.25 4 4.5/4.3 154.4 175 175 4 460-3-60 4 16.4 95.0 460-3-60 1.25 4 2.15 78.3 90 90 5 575-3-60 4 12.1 80.0 575-3-60 1.25 4 1.7 58.2 70 70 2 208/230-3-60 4 42.0 239.0 208/230-3-60 1.50 4 5.8 201.7 225 225 4 460-3-60 4 19.2 125.0 460-3-60 1.50 4 2.9 93.2 110 110 5 575-3-60 4 13.8 80.0 575-3-60 1.50 4 2.2 67.5 80 80 2 208/230-3-60 4 47.1 350.0 208/230-3-60 1.50 4 5.8 224.7 250 250 4 460-3-60 4 25.0 158.0 460-3-60 1.50 4 2.9 117.9 125 150 5 575-3-60 4 19.9 125.0 575-3-60 1.50 4 2.2 93.4 110 110
Compressor Fan Motor
RLA
(each)
LRA
(each)
Power Supply HP Qty. FLA (each)
Unit
Ampacity
(Amps)
278806-BIM-A-1106
Max. Fuse
Size
(Amps)
Disconnect
Min.
Size
REFRIGERANT MAINS
Many service problems can be avoided by taking ade­quate precautions to provide an internally clean and dry system and by using procedures and materials that conform to established standards.
Use hard drawn copper tubing where no appreciable amount of bending around pipes or other obstructions is necessary. If soft copper is used, care should be taken to avoid sharp bends that may cause a restric­tion.
Pack fiberglass insulation and a sealing material such as permagum around refriger ant lines whe re they pen­etrate a wall to reduce vibrations and to retain some flexibility.
Support all tubing at minimum intervals with suitable hangers, brackets or clamps.
Braze all copper-to-copper joints with Silfos-5 or equiv­alent brazing material. Do not use soft solder.
Insulate all suction lines with a minimum of 1/2" ARMA­FLEX or equal. Liquid lines exposed to direct sunlight and/or high temperatures must also be insulated.
Never solder suction and liquid lines together. They can be taped together for convenience and support purposes, but they must be completely insulated from each other.
The liquid and suction connections permit leak testing, evacuation, and partial charging of the field piping and
the evaporator without disturbing the condenser coils during initial installation.
Before beginning installation of the mains, be sure that the unit has not developed a leak in transit. If pressure still exists in the system, it can be assumed to be leak free. DO NOT release the holding charge.
A filter-drier MUST be field-installed in the liquid line of every system to prevent dirt and moisture from damag­ing the system. Properly sized filter-driers are shipped with each condensing section.
NOTE: Installing a filter-drier does not eliminate the
need for the proper evacuation of a system before it is charged.
A field-installed moisture indicating sight-glass should be installed in the liquid line(s) between the filter-drier and the evaporator coil. The moisture indicating sight­glass can be used to check for excess moisture in the system or used as a visual means to verify refrigerant charge.
All lines have a copper disc brazed over the end. Also, if the unit does not have service valves, the holding charge must be reclaimed to allow th e installer to con­nect piping. The temperature required to make or bre ak a brazed joint is sufficiently high to cause oxidation of the copper unless an inert atmosphere is provided.
NOTE: Dry Nitrogen should flow through the system at
all times when heat is being applied and until the joint has cooled.
10 Unitary Products Group
278806-BIM-A-1106
Remove the evaporator holding charge and any caps or discs on the liquid and suction connections that will not permit a free flow of nitrogen.
NOTE: Always drill a small hole in sealing caps and
discs before unbrazing to prevent the pressure in the line from blowing them off.
NOTE: S olenoid and hot gas bypass valves (if used)
should be opened manually or electrically dur­ing brazing or evacuating.
The evaporator coil section is shipped with the side panels suitable for right end piping connections wh en viewed from the return air ends of the section.
Begin the refrigerant mains by installing the liquid line from the condensing unit to the evaporator liquid con­nection, maintaining a flow of nitrogen during all braz­ing operations. The filter-drier and sight glass must be located in this line, close to the evaporator. Make the suction line connection at the evaporator and run the line to the condensing unit.
For Units Without Service Valves - Reclaim the refrigerant holding charge prior to op ening any portion of the system. Connect a low pressure Nitrogen source to the suction and liquid line service ports on the con­densing unit. Drill a small hole in the sealing disk; the flow of Nitrogen will prevent any debris from entering the system. Unbraze the sealing disk and prepare the joint for connections of the main lines. Connect the lines while maintaining a flow of Nitrogen from the liq­uid line service port through the evaporator, back to the condensing unit and out the suction service port.
For Units Equipped With Service Valves - Verify the service valves are fully seated by screwing the stem down into the valve body until it stops. Connect a low­pressure nitrogen source to the service port on the valve body. The flow of Nitrogen will prevent oxidation of the copper lines during installation. Drill a small hole in the sealing disk; the flow of Nitrogen will prevent any debris from entering the system. Wrap the valve body with a wet rag to prevent the valve body from overheat­ing during the brazing process. Overheating the valve will damage the valve seals. Ensure the valve is ade­quately protected prior to any brazing on the valve body. Unbraze the sealing disk and prepare the joint for connections of the main lines. Connect the lines while maintaining a flow of Nitrogen from the liquid line valve service port through the evaporator, back to the condensing unit and out the suction valve service port.
Once the brazing process is complete, leak testing should be done on all interconnecting piping and the evaporator before proper evacuation to 500 microns is performed. Once the line set and evaporator section is properly evacuated the service valves can be opened and the condensing unit is now ready to charge with the appropriate weight of refrigerant.
LINE SIZING
When sizing refrigerant pipe for a split-system air con­ditioner, check the following:
1. Suction line pressure drop due to friction.
2. Liquid line pressure drop due to friction.
3. Suction line velocity for oil return.
4. Liquid line pressure drop due to vertical rise. Tables 6 and 7 list friction losses for both the suc­tion and liquid lines on the condensing section. For certain piping arrangements, different sizes of suc­tion line pipe may have to be used. The velocity of the refrigerant vapor must always be great enough to carry the oil back to the compressor.
Evaporator Below Condensing Section - On a split system where the evaporator blower is located below the condensing section, the suction line must be sized for both pressure drop and for oil return. See Table 6.
Condensing Section Below Evaporator - When the condensing section is located below the evaporator blower, the liquid line must be designed for the pres­sure drop due to both friction loss and vertical rise. See Table 10. If the pressure drop due to vertical rise and friction exceeds 40 psi, some refrigerant will flash before it reaches the thermal expansion valve.
Flash gas
:
1. Increases the liquid line pressure loss due to fric­tion that in turn causes further flashing.
2. Reduces the capacity of the refrigerant control device that starves the evaporator.
3. Erodes the seat of the refrigerant control device.
4. Causes erratic control of the refrigerant entering the evaporator.
SERVICE VALVES
These condensing units may have service valves on the compressor suction line and on the liquid line
Unitary Products Group 11
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