Carrier 38GP User Manual

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Page 1

Carrier International

Corporation

Installation, Operation,

and Maintenance Instructions

Important—Read Before Installing

Check the power supply: Voltage, frequency, and phase must correspond to that specified on the unit rating plate. The power supply must be able to handle the additional elec trical load imposed by this equipment.

The Model 38GP Condensing Unit does not have a trans former; therefore, the fan-coil or blower package trans former (or another source) must be used as a low-voltage supply. The low-voltage supply must have an additional capacity of 15VA to handle the load imposed by this equipment.

The compressor motor is equipped with em internal protec tor. Excessive current or temperature wiU cause the protec tor to open, giving the indication of an open circuit in the motor winding. Sufi&cient time should be allowed for the overload to reset before assuming the compressor has an open winding.

The compressor motor is designed to start under low-load

conditions only (high- and low-side pressures equalized) and within the specified operating voltage range. Make sure that system pressures have equahzed before attempting to start the unit. Equahzation takes approximately 3 minutes. The owner should be informed not to short-cycle the unit with the thermostat as this wiU cause the compressor to tripout on overload.

Each condensing unit is shipped with a refrigerant charge that is adequate for most systems using matching coils and refrigerant tubing kits. This charge is adequate for up to 25 feet of interconnecting tubing. For tube lengths greater or less than 25 feet, the refrigerant charge must be adjusted. See Table II for charge quantity and refer to refrigeranttube sizing. Tables IV through VII, for the adjustment re quirements.

NOTE: If additional refrigerant is needed, a crankcase heater

wül probably be required. (Refer to the appropriate refriger ant-tube sizing table.) When a crankcase heater is used, inform the homeowner that power must be turned on to the air conditioning unit at least 12 hours before the thermostat is turned to the COOLING position for spring startup.

A filter-drier is not normally required in the system when a complete system is used (condensing unit, refrigerant tub ing, and evaporator coil). For exceptions to this rule, see Section II, “Installing Refrigerant Tubing,” of the Stand ard Installation Practices booklet packaged with the unit.

To obtain optimum performance and efficiency with match ing or mix-matched evaporator coils, it may be necessary to change the metering device. See Table IX for necessary changes.

^Carrier International Corporation 1984

38GP

(50-HZ)

Figure 1—Model 38GP

GENERAL

The condensing unit, as shipped from the factory, includes: a compressor, a condenser fan and motor, hquid and suction service valves, an air-cooled condenser coil, and all neces sary electriceil controls.

The condensing unit is designed for use with matching evaporator coils. An expansion valve is not required. How ever, the unit can be used with a suitable evaporator coil that uses an expansion valve with a pressure equalization feature during the off cycle. Expansion valves with this fea ture.are available from your Distributor.

Installation comprises the following steps (sections):

I. Locating the Unit

II. InstaUing Refrigerant Tubing

III. Leak Testing

IV. Purging (if required)

V. Evacuation (if required)

VI. Electrical Connections

VII. Checking Charge

VIII. Adjusting Charge

38GP-C12SI-CIC

Page 2

AIR IN

NOTE: Fan position on motor shaft should be as close to motor as possible without touching.

Figure 2—Dimensional Drawing

TABLE I—DIMENSIONS (In Inches)

Size

025

040, 047 & 054

----------X---------27-3/8 24-9/16 6-3/8 1-7/8 3/8 27-3/8 30-9/16 6-3/8 1-7/8 3/8

----------C----------

----------1----------

F G

11-9/16 11-9/16

H 11-3/4 11 -3/4

11/32 3/4 11/32

3/4

TABLE II—SPECIFICATIONS

Refrigerant Type R-22

Size 025

Factory Refrigerant Charge Lbs-oz 4-8

040

R-22 R-22

6-8 7-2 Refrigerant Tube^ Liquid 3/8 3/8 Connection Size (Compatible) Vapor 3/4 3/4 Approx Shipping Weight Lbs 155 200

♦Refer to appropriate refrigerant tube sizing table to determine correct liquid- and suction-tube diameters.

047

3/8 3/4

230

054 R-22 6-11

3/8 3/4

232

TABLE III—ELECTRIC CONNECTIONS

Nameplate

Size 025 040

Volts—Phase (60-Hertz) 230—1—50 Operating Voltage Range

207-253 360-440 360-440 360-440 360-440

400—3—50

Unit Ampacity for Elec trical Conductor Sizing. 18.5 6.7 9.2 14.1 Total Unit Amps 15.1 5.6 7.6 Min Branch Circuit Wire Size Copper Conductor^

AWG No.

Max Length

In Ftt

12 14 14 14

94 321 236 156 228

Largest Wire Size Terminal Will

, Accommodate

Type Conn

AWG No. 6

Screw Screw

6 6 6 6

Screw

Max Branch. Circuit Fuse Sizet

Amps 25

NOTE: Use copper wire only between disconnect switch and unit.

♦If other than 75° C copper conductor is used, determine size from unit-ampacity and the National Electric Code. Voltage drop of wire must be less

than 2% of unit rated voltage. fLength shown is as measured one way along the wire path between the unit and service panel-for minimum 2% voltage drop. $Sing)e-phase units may use fuses or HACFI-type circuit breakers of same size as noted.

047 054

400—3—50 400—3—50

15.4

11.5 12.5

Screw Lug

20 20

Page 3

All of the above steps are covered in general by the likenumbered sections of the Standard Installation Practices in the back of this manual; therefore, this Installation Instruc tion will contain only supplementary information applicable to installing the condensing unit. It should be noted that evacuation and purging are not normally required when a

complete matching system is installed. However, if any of the component parts are subject to contamination, or if tub ing kits and matching coUs are not used, the system must be purged or evacuated.

NOTE; Be sure to adjust system airflow per requirements of

the fan-coil, evaporator coil, and condensing unit combination.

In addition, the following sections should be reviewed by the equipment owner;

IX. Sequence of Operation

X. Care and Maintenance

I. LOCATING THE UNIT

(Supplementary Instructions)

Select a location for the unit where water, ice, emd snow will not fall from an overhang and damage the unit top or fan blade. Care must be exercised to maintain the clearance requirements listed on page 2 to assure proper access for servicing and to avoid recirculation of condenser air.

II. INSTALLING REFRIGERANT TUBES (Supplementary Instructions)

A. Determining Liquid-Tube Diameter

The correct liquid-tube diameter cem be determined by using the appropriate table as described in steps 1 through 7 which follow. Be certain to use only the hquid-tube table that matches the size unit being installed. (See Tables IV thru VII.)

1. Measure total one-way horizontal distance for intended tubing path.

2. Measure total one-way vertical distance for intended tubing path.

3. At left-hand end of table, select value that matches measured vertical length. Be sure to note that upper section of table is used if coohng coü is above unit, whereas lower section is used if cooUng coil is below

unit.

4. Move across this Une towards right-hand side until cor

rect vertical column is reached for measured horizontal length.

5. Correct diameter will be indicated at intersection of

these lines.

6. If point of intersection falls within shaded area, crank case heater must be added.

7. For apphcations where coohng coil is to be placed more than 50 feet below unit, see your Distributor for spe cific recommendations.

Here is an example; Unit is size 025. Coohng coil is located 43 feet above unit. Horizontal distance is 72 feet.

First, in the section marked “Coü Above Unit,” find the hne showing measurement of 41-50 feet. Follow this line towards the right until it intersects the vertical colunrn marked 71-80 feet. The correct tube size is 5/16-inch OD, and the fact that the 5/16-inch size falls in the shaded area

means that the unit wih require a crankcase heater.

B. Instructions for Total System Charge

The total system refrigerant charge includes the condensing unit, the evaporator coü, and the interconnecting tubing. The factory charge is sufficient for a system using 25 feet of

interconnecting tubing and a matching evaporator coil. For systems using tubing lengths other than 25 feet, adjust the charge in accordance with the notes under the proper table (IV through VII).

TABLE IV—UNIT SIZE 025

Vertical

Distance to to to

(Ft) 10 20 30 40

Coil

Above 21 to 30 1/4 1/4

Unit

Coil

Below

Unit

41 to 50

31 to 40, 1/4

11 to 20 1/4 1

Oto 10 Oto 10

11 to 20 21 to 30 31 to 40 1/4 41 to 50 1/4 1/4 51«; /3«,

D 11 21 31

5/16 5/16 5/46 5/16

Horizontal Distance- -Feet

to to to

5/16 5/-16 5/16

4,/4,<

41 51

50 60 70 80 90 100

61 to to

5/16

71 81 91

to to

5/16 3/8

5/16

1/4

5/16

5/J6

5/16

TABLE V—UNIT SIZE 040

Horizontal Distance— Feet

Vertical a

Distance to to to to to to to to to to

(Ft)

Coil 31 to 40

Above 21 to 30 1./4

Unit 11 to 20 1/4

Coil 11 to 20

Below

Unit

41 to 50 1/4 5/16 5/16 5/16 5/16 5/16 5,'16 5/16 5/16 5/16

Oto 10 1/4 Oto 10 1/4

21 to 30 1/4 31 to 40 41 to 50 1/4 1/4 1/4 1/4 1/4 1,-4

11 21 31 41 51 61 71 81

10 20 30 40 50 60 70 80 90 100

1/4

5/16

5./16

5/16

TABLE VI—UNIT SIZE 047

Horizontal Distance— Feet

Vertical 11 21 31

Distance to to to to to to to to to to

(Ft)

41 to 50 5/16 5/16 3/8 3/8

Coil 31 to 40 5/16 5/16

Above 21 to 30 5/16

Unit 11 to 20 5/16 5/16

Oto 10 Oto 10

Coil 11 to 20

Below 21 to 30

Unit 31 to 40

41 to 50 5/16 5/16 5/16 5/16 5/16 5/16 5/16 5/16 5/16

10 20 30 40 50 60 70 80 90 100

51 61 71 81 91

3/8 3/8 3/8

3/8

m/§

5/16

5/16 5/16

5/16

TABLE VII—UNIT SIZE 054

Vertical 11 21 31 41 51 61 71 81 91

Distance to to to to to to to to to to

(Ft)

Coil 31 to 40

Above 21 to 30

Unit 11 to 20 5/ 5.'16

Coil

Below

Unit

(1) Unit charge adequate for 3/8-in. OD tube lengths up to 25 ft. For lengths

(2) Unit charge adequate for 1/4-in. OD tube lengths up to 75 ft. For lengths

(3) Unit charge adequate for 5/16-in. OD tube lengths up to 40 ft. For lengths

(4) If tube size falls within shaded area, add crankcase heater.

41 to 50

Oto 10 Oto 10

11 to 20 21 to 30 31 to 40 41 to 50 5/16

below or above 25 ft, adjust charge at rate of 0.6 oz/ft. This may be done by using superheat charging label.

above 75 ft, adjust charge at rate of 0.2 oz/ft.

above 40 ft, adjust charge at rate of 0.4 oz/ft.

3/8 3/8 3/8 3/8

5/ 16

' ’

Horizontal Distance— Feet

30 40 50

5.'16] 5/ 1 6

5/16|5/16|5/16|5/16|5/16 3/8 3/8 3/8 3/8

3 5

i J

70 80 90

3./8 3/8 3/8 3,'8 3/8

5/16

5 1 6

...

100

—3—

Page 4

TABLE Vili—RECOMMENDED

SUCTION-TUBE DIAMETERS

Suction-Tube

Size

025 0 to 120 5/8

040 Oto 60

047

054 0 to 65 1-1/8

NOTE: The above table is based on a tube loss of 2°F. Longer lengths

can be used in each diameter listed, or smaller diameters may be used, but the result will be larger tube losses with a lower unit capacity and efficiency rating. Refer to your Distributor for specific details.

Length (Feet)

120 to 150 7/8

60 to 135 7/8

Oto 85 7/8

85 to 150 1-1/8

65 to 150 1-3/8

Recommended

Diameter (inches)

3/4

TABLE IX—REQUIRED PISTON SIZE FOR

INDOOR COIL

Condensing

Unit Size

025 040 76 047 054 88

NOTE: The piston sizes listed in this table are for systems where the

vertical separations between indoor and outdoor units do not exceed 10 feet. For vertical separations exceeding 10 feet, consult the factory for the proper piston sizes.

Piston

identification No.

If other than matching interconnecting tubing or evapora tor coU is being used, use an accurate scale or volumetric charging cylinder (such as a Dial-A-Charge) and weigh in the refrigerant until the desired superheat temperature is obtained. See the superheat charging label attached to each condensing unit.

When system charging has been completed, stamp the total

amount of refrigerant in the block provided on the condens ing unit rating plate. The total system charge is the same as the field charge.

C. Determining Suction-Tube Diameter

The correct suction-tube diameter can be determined by using Table VIII as follows:

1. Measure total length (vertical and horizontal) of intended tubing path.

2. Find correct unit size at left of table. The tube lengths are shown in the center of the table

with the appropriate diameters on the right.

iX. SEQUENCE OF OPERATiON

When the thermostat “calls for cooling,” the thermostat contacts close, energizing contactor holding coil 2D or 2M from a 24-volt external power source. The contactor closes, energizing compressor motor 3F or 3J and condenser fan motor 3C or 3D with supply voltage.

When the thermostat is satisfied, the contacts open, deenergizing contactor holding coil 2D or 2M and, in turn, breaking the supply voltage circuit. AH motors should stop.

Optional Start Assist (When Used)

Start thermistor 4K is wired in parallel to run capacitor 4G on single-phase units. Its purpose is to provide additional start assist. When compressor 3J starts, start thermistor 4K builds its internal resistance to a level where it effec

tively removes itself electrically from circuit. When contac tor 2D or 2M is deenergized, start thermistor 4K will auto matically reset itself in approximately 3 to 5 minutes.

Start Kit 2K and 4D

The start kit consists of start relay 2K and start capacitor 4D. Start capacitor 4D helps compressor 3J start. When the compressor starts, start relay 2K disconnects start capaci tor 4D from the circuit, allowing compressor 3J to run on run capacitor 4A or 4G. When contactor 2D or 2M deener gizes, start relay 2K reconnects the start capacitor in the circuit, making it ready for the next compressor start.

X. CARE AND MAINTENANCE

For continuing high performance, and to rnmirnize possible equipment failure, it is essential that periodic maintenance be performed on this equipment. Consult your local Dealer for the proper frequency or maintenance and the availability of a maintenance contract.

The air for the condenser coil is drawn into the unit on four sides and discharged out the top. Keep the air inlet and out let grilles unplugged and clear of any obstructions at all times. Never cover the unit or lean anything against it which might restrict airflow or cause hot air from the top grille to recirculate into the sides. Keep trash and debris away from the uiut at all times. Never stand on the unit or use it as a support for ladders, etc.

The refrigerant tubing connecting this unit with the coohng coil is easily crushed or crimped. Therefore, do not hang or stand anything on it. Do not move the unit after it has been installed, as this may crimp the tubing and cause the unit to malfunction.

The ability to properly perform maintenance on this equip ment requires certain mechanical skills and tools. If you do not possess these, contact your Distributor for maintenance.

The minimum maintenance that should be performed on this equipment is as follows:

1. Check condenser coü for cleanliness each month during cooling season. Clean as necessary, but at least once at the beginning of each cooling season. To insure reliable performance in sea coast or contaminated atmosphere installations, the unit must be kept free of debris and the condenser coil flushed with fresh water at least once a month. See Section X, item A, for proper procedures.

—4—

Page 5

TERMINAL

BLOCK

Figure 3—Typical Single-Phase Wiring

--------

FIELD LOW VOLTAGE ooo

---------

FIELD HIGH VOLTAGE

----------

FACTORY LINE VOLTAGE XXX

----------

FACTORY LOW VOLTAGE

2A-Contactor SPST 2D-Contactor DPST 2K-Start Relay (When Used) 2M-Contactor TPST (N.O.) 3C-Condenser Fan Motor 3D-Condenser Fan Motor 3J-Compressor (Single-Phase) 3F-Compressor (3-Phase)

FIELD WIRING DIAGRAMS

Figure 4—Typical Three-Phase Wiring

STARTING CIRCUIT LINE VOLTAGE (WHEN USED) ALTERNATE STARTING CIRCUIT LINE VOLTAGE (WHEN USED)

LEGEND

4A1 -Run Capacitors 4D-Start Capacitor (When Used) 4G-Run Capacitor (Dual)

4K-Start Thermistor (When Used)

11 A-Crankcase Heater (When Used)

3-0 DNIT

! ! 1 ! ^

WIRE NUT ] 1

\ Ml

MLJL J

R # 1

Figure 6—With Fan-Coil Unit

(For cooling-only, delete W.)

LL J r-

Figure 5—Typical Field Low-Voltage Wiring

--------

FIELD LOW-VOLTAGE WIRING

--------

FIELD HIGH-VOLTAGE WIRING

--------

FACTORY LOW-VOLTAGE WIRING

FIELD-SUPPLIED FUSED DISCONNECT

•

—-[TD*Ti--

• >

. »

•HI-»-

----

-HI

•HP»-

—-^T~n^-

-----

I SINGLE

fPHASE

—5—

©--■

(¡>------------

------

FIELD LOW-VOLTAGE WIRING

------

FIELD HIGH-VOLTAGE WIRING

------

FACTORY LOW-VOLTAGE WIRING

•Hh-»--

• •-

•HP»-

--OZZEkf»

•HI-»-

/^GND

Figure 7—With Blower Package (For

cooling-only, delete W.)

—

Page 6

Check fan motor and blade for cleanliness and lubrica tion each cooling season. Clean and lubricate as necessary.

Check electrical connections for tightness and controls for proper operation each cooling season. Service as

necessary.

A. Condenser Coil

Remember to disconnect electrical power before removing any panels.

Since the air is drawn into the sides of the unit and dis charged out the top, most of the dirt will collect on the out side surface of the coil. However, some dirt will penetrate the coil. This condition is very difficult to see without removing the top cover.

To properly check the condenser coil for cleanliness, or to

clean the coil; proceed as follows:

1. Remove top cover. Enough motor wire is provided so that the top cover can be lend on edge without discon necting the motor leads. (CHp wire tie to release wire.)

2. Clean coil by spraying from inside outward with highvelocity stream of water. (Garden hose is sufficient.)

Be careful not to damage the coil fins. Be sure to wash the dirt from the coil. Space has been provided under the coil to flush away the dirt. Drain holes are also provided in the base pan. Be sure they are open. If the coil is coated with oil or grease, it can be cleaned with a mUd detergent or an ap proved coil cleaning agent, then rinsed with clear water. Be careful not to get water in the compressor and unit control boxes.

B. Condenser Fan Motor and Blade

Remember to disconnect electrical power before removing any panels.

1. Remove screws holding top cover.

2. Lift top with motor and fan blade out of hole. Do not cut or stretch motor electrical leads. Be careful not to bend fan blade.

3. Clean motor and blade with soft brush or rag. Be care ful not to disturb balance weights on fan blade.

4. Check fan blade setscrew for tightness.

5. Lubricate fan motor. a. Remove dust caps or plugs from oil holes located at

each end of motor.

b. Use teaspoon, 5cc, 3/16 oz, or 16 to 25 drops of good

grade SAE 20 nondetergent motor oil in each hole. AUow time for total quantity to be absorbed by each bearing.

c. Wipe excess oil from motor housing.

d. Replace dust caps or plugs in oil holes.

SYMPTOM CAUSE

Compressor and condenser

fan will not start

Compressor will not start,

but condenser fan runs.

Compressor cycle (other than

normally satisfying thermostat).

Compressor operates

continuously.

Excessive head pressure

Head pressure too low

Excessive suction pressure

Suction pressure too low

Power failure Call power company. Fuse blown or circuit breaker tripped

Defective thermostat, contactor, or control relay Low line voltage Incorrect or faulty wiring Thermostat setting too high Faulty wiring or loose connections in compressor circuit Compressor motor burned out, seized, or internal overload open Defective run capacitor Determine cause and replace. Refrigerant over or under charged Defective compressor Replace and determine cause. Low line voltage Determine cause and correct. Blocked condenser Determine cause and correct. Defective run capacitor Defective thermostat Faulty condenser fan motor or capacitor Replace. Restriction in refrigerant system Unit undersized for load

Thermostat set too low ♦Reset thermostat. Low refrigerant change Leaking valves in compressor Replace compressor. Air in system Blow refrigerant, evacuate system, and recharge. Condenser coil dirty or restricted Dirty condenser coil Refrigerant overcharged Purge excess refrigerant. Air in system Blow refrigerant, evacuate system, and recharge. Condenser air restricted or air short-cycling Eliminate cause. Low refrigerant charge Compressor valves leaking Replace compressor. Restriction in liquid tube Remove restriction. High heat load Check for source and eliminate. Compressor valves leaking Refrigerant overcharged Purge excess refrigerant. Low refrigerant charge Metering device or low side restricted Low evaporator air Increase air. Temperature too low in conditioned area ♦Reset thermostat.

♦Thermostat should be set between 72° and78°F.

TABLE X—TROUBLE ANALYSIS CHART

REMEDY

Replace fuse or reset circuit breaker. Replace component.

Determine cause and correct. Check wiring diagram and rewire correctly. ♦Lower thermostat setting below room temperature. Check wiring and repair or replace.

Replace compressor and determine cause.

Blow refrigerant, evacuate system, and recharge.

Determine cause and replace.

Replace thermostat.

Locate restriction and remove. Decrease load or increase unit size.

Locate leak; repair and recharge.

Clean coil or remove restriction. Clean coil.

Check for leaks; repair and recharge.

Replace compressor.

Check for leaks: repair and recharge. Remove source of restriction.

—6—

Page 7

6. To reassemble unit: a. Reinstall top cover with fan motor and blade.

b. Push excess motor leads back into wire retainer and

replace all screws.

c. Reconnect electrical power and check fan for proper

operation.

C. Electrical Controls and Wiring

With power disconnected to unit, check all electrical connec tions for tightness. Tighten aU screws on electrical connec tions. If any smoky or burned connections are noticed, dis assemble the connection, clean aU parts and stripped wire,

Standard Installation Practices

reassemble properly, (Use new connector if old one is burned or corroded.) and secure tightly. Electrical controls are diffi cult to check without proper instrumentation; therefore, reconnect the electrical power to the unit and observe the unit through one complete operating cycle.

If there are any discrepancies in the operating cycle, contact your Distributor and request service.

D. Refrigerant Circuit

The refrigerant circuit is difficult to check for leaks without

proper equipment. Therefore, if low cooling performance is

suspected, contact your local Distributor for service.

This Standard Installation Practices publication is intended for use with all electric air conditioning units ranging from 14,000 thru 60,000 Btuh.

Modern air conditioning systems consist of a remotely located condensing unit, an evaporator coU, and intercon necting refrigerant tubes. The proper installation of each of these components wUl insure that the system wiU provide the comfort for which it is designed. The following pages list the minimum steps to be taken during the installation of an air conditioning unit.

In general, the condensing unit should be located remotely from the evaporator coil and have adequate clearances for airflow and service. The evaporator coil should be located in an air handler that has enough capacity to load the coil and, the refrigerant tubes should be as short as practical. Extreme care should be taken when installing the system to avoid contaminating it with edr and moisture: Either con taminant will cause a system failure.

When the system is placed in operation, it is important that

the homeowner be informed of the maintenance steps required to keep the system in proper operation. Among these are the following:

1. Keep air filter in place when system is in operation; replace or clean it regularly.

2. Keep condenser coü clean, and do not obstruct airflow.

3. If system has crankcase heater, turn on power to unit at least 12 hours before thermostat is turned to cooling for spring startup.

4. It is not recommended that condensing unit be oper ated below 55° F outdoor temperature. If operation

below this temperature is desired, an optional lowambient kit is available from your Distributor.

The following sections, when used in conjunction with the detedled unit instructions, Eire the steps needed to complete the installation of an air conditioning system. If more detailed instructions are required, see your Distributor.

I. LOCATING THE UNIT

This condensing unit is approved for outdoor installations.

1. Consult local codes or ordinances for restrictions regarding location of unit.

2. Consult dimensional drawing for following: a. Location of refrigerant connections and electrical

connections.

b. Recommended clearEmces.

c. Direction of condenser airflow.

d. Mounting base dimensions.

3. Place unit on level base strong enough to support

weight of unit and to resist effects of frost heaving, etc. Concrete lintels can be used if spaced to adequately support unit.

4. AUow air to circulate under unit. Legs or bases are pro vided on most units for this purpose. If legs or bases are not provided, spacers can be obtained from your Distributor—or unit may be set on a bituminous mix ture, such as roofing tar, to prevent base pan from rust ing. Do not plug drain holes.

5. On rooftop applications, locate unit at least 6 inches above roof surface. Where possible, place unit above a load-bearing wall. Arrange supporting members to ade quately support unit and minimize transmission of vibration to building. Either precast concrete lintels, concrete blocks, treated timbers, or steel beams can be

used. Consult local codes governing rooftop appli cations.

6. Avoid locations where flowers, shrubs, etc. are in path

way of condenser discharge air, or where condenser f£m wiU discharge against prevailing wind or building. Select a location for the unit where ice and snow wiE not faE from an overhang and damage the unit top or fan blade.

7. Avoid locations where normal operating sounds may be objectionable, such as beneath windows, between struc tures, or near patios. Should operating sounds be objec-

-7—

Page 8

tionable, consideration should be given to a shielding barrier. Consult your Distributor or the current pubhcation of ARI Standard 270 for assistance in determin ing a suitable location with minimum of operating sounds.

8. Keep distance between evaporator coil and condensing unit as short as possible.

9. Consult your Distributor regarchng roof-mounted con densing units on multilevel buildings.

OPENING AND CLOSING OF VALVES

1. Use correct tool.

2. Remove valve stem cap.

3. Front-seat—turn clockwise until valve stem bottoms. Do not overtighten.

4. Open—turn counterclockwise until stem just contacts snapring in valve body. Do not overtighten.

5. Replace valve stem cap and be sure that it is tight.

II. INSTALLING REFRIGERANT TUBES

IMPORTANT: The condensing unit is charged at the fac tory. Be sure both service valves are front seated (turned clockwise) to avoid loss of the charge. DO NOT REMOVE REFRIGERANT TUBE CONNECTION SEALS FROM THE CONDENSING UNIT, THE MATCHING EVAPO RATOR COIL, OR THE REFRIGERANT TUBING, UNTIL READY TO MAKE THE ACTUAL CONNEC TION AT THE POINT OF SEAL.

If either refrigerant tubing or evaporator coil is exposed to atmospheric conditions for longer than 5 minutes, they must be purged. See Section IV, “Purging,” for the proper method.

If other than matched refrigerant tubing is used, select an approved (type-L) refrigerant tubing of the correct size. (DO

NOT USE WATER TUBING.) Flare this tubing, using a stand

ard 45-degree SAE flaring tool. Insulate the suction tube with an insulation having an adequate vapor barrier (e.g. Armaflex or Ensolex). It wiU be necessary to evacuate this tubing and evaporator cod. See Section V, “Evacuation,” for proper method.

NOTE: All refrigerant tube joints erected on the premises

should be exposed to view for visual inspection and leak testing before being covered or enclosed.

When a complete system (condensing unit, refrigerant tub ing, and evaporator cofl.) is used, a filter-drier is not required in the system. However, if other than matched refrigerant tubing or coils are used, or if the refrigerant tubing or coil is exposed to atmospheric conditions for longer than 10 min utes; a filter-drier must be installed in the system at the coil. (An appropriate size of filter-drier is available from your Distributor.)

NOTE; Additional refrigerant must be added to the system

and compensate for the additional volume of the filter-drier, and different tubing lengths.

Install refrigerant tubes as follows:

1. Consult local codes or ordinances before running refrig erant tubes.

2. Install evaporator coil in accordemce with instructions packaged with coil.

3. If evaporator coil requires thermal expansion valve, obtain proper valve from your Distributor and install in accordance with instructions packaged with evapo rator coil.

4. Run refrigerant tubes as directly as possible, avoiding unnecessary turns and bends.

5. Tape liquid tube to top of insulated suction tube for support. See Figure 3.

6. Suspend refrigerant tubes so they do not damage insu lation on suction tube and do not transmit vibration to structure. See Figure 3. Also, when passing refrigerant tubes through wall, seal opening so vibration is not transmitted to structure. Leave some slack in refriger ant tubes between structure and unit to absorb vibration.

7. If refrigerant tubes are too long, they should be rolled into loop and placed in horizontal plane with end leav ing loop going to compressor, coming out of bottom. If

desired, excess may be cut off and tubing braised.

8. Be sure both service valves are front seated (turned clockwise). It is necessary to remove valve stem caps to check.

9. When required, connect filter-drier (available from your Distributor) in hquid tube at evaporator coil.

NOTE: The flow directional arrow, located on the label of the

filter-drier, must point toward the evaporator coil.

10. Connect tubing to condensing unit and evaporator coil, as shown in Figure 2. DO NOT REMOVE SEALS

UNTIL READY TO MAKE THE ACTUAL CON NECTIONS AT POINT WHERE SEAL IS REMOVED.

11. Refrigerant tubing and evaporator coil is now ready for

leak testing.

III. LEAK TESTING

No installation is complete until the entire system has been checked for leaks. This check should include aU field and fac tory joints. To check a system for leaks, proceed as follows:

1. Remove valve stem caps from both service valves and check to be sure valves are front seated (turned clock wise). Remove gauge port caps.

2. Attach gauge manifold to ports on service valves.

Hoses of gauge manifold must have valve core depressors.

3. Pressurize evaporator coil and interconnecting refriger

ant tubing with vapor from an external refrigerant cyl inder of R-22 until system and cyUnder pressures are equalized.

NOTE: NEVER USE A UNIT CHARGE FOR LEAK

TESTING.

4. Leak-test with electronic detector, halide torch, or hquid-soap solution.

5. Release pressure and repair any leaks found. Repeat leak test as necessary.

When system is free of leaks, proceed as follows:

If system is to be purged, leave service valves in

front-seat position. Leave gauge manifold attached to system and proceed to Section IV.

If system is to be evacuated, leave service valves in

front-seat position. Remove refrigerant cylinder from gauge manifold and proceed to Section V.

If system is to be started and the checking charge

procedure is to follow, open (counterclockwise) both service valves. Then proceed to step 3, Section VII.

If system is to be left in the leak-tested condition,

open (Turn counterclockwise.) both service valves

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Page 9

and remove gauge manifold. Replace caps on gauge

ports and valve stems. Be sure they are tight!

IV. PURGING

If either the refrigerant tubing kit or the evaporator coil is

exposed to atmospheric conditions during installation for longer than 5 minutes, the refrigerant tubing and the evapo rator con must be purged.

NOTE: DO NOT USE THE UNIT CHARGE TO PURGE

THE REFRIGERANT TUBING. To purge the refrigerant tubing and the evaporator coil, proceed as follows:

1. Disconnect hose from low side of gauge manifold.

2. Open valves on R-22 refrigerant cylinder and high side of gauge manifold. Allow approximately 1/2 to 1 pound of refrigerant vapor to flow through system and out hose attached to gauge port on suction service valve.

1. Connect evacuation equipment to system through gauge manifold.

2. Evacuate system, following appropriate steps for type of evacuation equipment used.

3. Pressurize system with refrigerant to 10 psig and open (Turn counterclockwise.) both service valves.

4. Remove gauge manifold. Replace valve stem and gauge port caps on both service valves (Be sure they are tight.) if system is to be left in evacuated condition. It wfll not be necessary to remove gauge manifold if checking-charge procedure is to follow.

VI. ELECTRICAL CONNECTIONS

IMPORTANT: Before proceeding with the electrical con nections, make certain that the volts, hertz, and phase cor respond to that specified on the unit rating plate. Also, check to be sure that the service provided by the utility is sufiicient to handle the additional load imposed by this equipment. Refer to the Ratings and Performance table in the detailed unit instruction and unit rating plate for equip ment electrical requirements.

The attached wiring diagrams show the proper field highand low-voltage wiring. Make all electrical connections in accordance with the National Electrical Code and any local codes or ordinances that might apply.

Use a separate branch electrical circuit for this unit. A dis connecting means must be located within sight of, and readily accessible to, the unit.

3. Pressurize system with refrigerant to 10 psig and close valves on refrigerant cylinder and gauge manifold. Reattach hose to low side of gauge manifold.

4. Open (Turn counterclockwise.) both service valves. Remove gauge manifold from gauge ports of service valves and replace valve stem and gauge port caps (Be sure they are tight.) if system is to be left in the purged condition, it wiU not be necessary to remove gauge

manifold if checking charge procedure is to follow.

V. EVACUATION

It is extremely important to have an installation in which aU refrigerant tubes and system components are completely free of air and moisture. If, during the installation, the

refrigerant tubing kit or the evaporator coil becomes con

taminated with moisture or liquid water, or other than matching components are used; the refrigerant tubes and evaporator coü must be evacuated.

If the installer can pull the system down to a reading of

1000 microns or less with his deep vacuum equipment, he can consider the system free of air and moisture when this level is reached.

If, however, the installer has an evacuation pump (one which will only pull a vacuum of approximately 28 inches) rather than a deep vacuum pump, he must triple-evacuate the system with the required number of purges and holding

periods. The initial preparation for evacuation of the refrig

erant tubing and evaporator coil is as follows:

NOTE: We require the use of copper wire between the dis

connect switch and the unit. Whenever aluminum wire is used in the branch circuit wiring with this unit, adhere to the following recommendations: Connections must be made in accordance with the National Electrical Code, using con nectors approved for aluminum wire. The connectors must be UL approved (marked Al/Cu with the UL symbol) for the application and wire size. In preparing the wire, just before

installing the connector, all aluminum wire must be “brushscratched” and coated with a corrosion inhibiter such as Pentrox A. When it is suspected that the connection wfll be exposed to moisture, it is very important to cover the entire connection completely to prevent an electrochemical action that will cause the connection to fail very quickly. Do not reduce the effective size of wire, such as cutting off strands so that the wire wfll fit a connector. Proper size connectors should be used.

If aluminum conductors are to be used, the wire size selected must have a current capacity not less than that of the copper wire specified, and must not create a voltage drop between the service panel and the unit in excess of 2% of the unit rated voltage.

Check all electrical connections (both factory and field) for

tightness. This should also be done after the unit has reached operating temperatures, especially if aluminum con ductors are used.

MR. ELECTRICIAN, PLEASE NOTE: DO NOT ATTEMPT TO OPERATE THIS CONDENSING UNIT

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Page 10

UNTIL ALL REFRIGERANT CONNECTIONS HAVE BEEN MADE AND BOTH SERVICE VALVES HAVE

BEEN CHECKED FOR THE OPEN POSITION.

(TURNED COUNTERCLOCKWISE.) IT IS NECESSARY

TO REMOVE THE VALVE STEM CAPS TO CHECK. The single-phase compressor motor used in this condensing

unit may be a permanent-spht-capacitor-tj^e (PSC) motor, designed to start under low-load conditions only; therefore, make sure that the system pressures have equahzed before attempting to start the unit: this takes approximately 3 minutes. Do not short-cycle the unit with the thermostat or disconnect, as this will cause the compressor to tripout on overload. For starting under most load conditions, an optional starting kit is available from your Distributor.

VII. CHECKING CHARGE

No installation is complete until the operating charge level of the unit is checked. The level of refrigerant operating

charge will determine how efficiently and economically the unit wiU operate. An overcharged or undercharged unit wiU lead to insufficient cooling, high operating costs, and the possibihty of a compressor failure. To check the refrigerant charge level, proceed as follows:

1. Remove valve stem caps from both service valves and check valve stems for open position (counterclockwise).

2. Remove gauge port cap from both service valves and attach gauge manifold. Purge gauge manifold and

hoses.

3. Start unit and allow it to run until operating conditions

stabihze and pressures level out.

4. Evaluate system performance and refrigerant charge

level by determining following information:

a. Low-side pressure gauge reading.

b. Dry-bulb temperature of inlet air at condenser coil.

c. Wet-bulb temperature of inlet air at evaporator coil.

This may be read at central return-air grille.

d. Liquid- or suction-tube temperature at respective

service valve.

NOTE: Use an accurate superheat, thermocouple, or

thermistor-type thermometer.

e. Compare these readings to those fisted on Unit

Charging Label located on unit. Add or remove refrigerant as required.

NOTE: The suction-tube connection of the compressor must

be as cool as the suction tube, and the compressor base should be warm.

5. When correct refrigerant charge level is obtained, remove gauge manifold.

6. Replace valve stem and gauge port caps. (Be sure they are tight.)

NOTE: Where applicable, stamp the total number pounds of

refrigerant charge onto the rating plate in the space

provided.

VIII. ADJUSTING CHARGE

If, after checking the operating charge level, the unit is found to be undercharged or overcharged, refrigerant may be added or removed through the gauge manifold and the suction service valve.

To add refrigerant to a unit, proceed as follows:

1. Connect clean, dry cylinder of R-22 to center port con

nection of gauge manifold. Purge hose and connect gauge manifold to service valves.

2. With refrigerant cylinder in upright position, open valve on cylinder and slowly open valve on low-pres

sure gauge of manifold. Add refrigerant in vapor form until proper amount has been added.

3. When correct refrigerant charge level is obtained, close valves on refrigerant cylinder and gauge manifold.

4. Remove gauge manifold from service valves. Replace valve stem and gauge port caps. (Be sure they are tight.)

To remove refrigerant from a unit, proceed as follows:

1. Slowly open valve on low-pressure gauge side of mani fold and vent refrigerant (slowly) through center port connection of gauge manifold.

2. When desired amount of refrigerant has been removed to obtain correct refrigerant charge level, close valve on low-pressure gauge side of manifold.

3. Remove gauge manifold from both service valves. Replace both valve stem and gauge port caps. (Be sure they are tight.)

CHECKOUT LIST

WITH ELECTRIC POWER OFF:

1. Check all electrical wiring (both factory and field) for completeness and tighten all electrical connections (contactor, capacitors, relays, etc.).

2. Check condenser fan blade for proper insertion depth in orifice plate.

3. Check evaporator blower puUey and motor pulley (beltdrive units only) for proper belt alignment and tight ness. (Should have 1 in. of sag with normeil finger

pressure.)

4. Tighten all setscrews (evaporator blower, blower pul

ley, motor sheave, and condenser fan blade).

5. Check condenser airflow for obstructions.

6. Clean or replace air filters. Do not operate system with

out air filters in place.

7. Leak-test all refrigerant connections (fittings, joints,

gaskets, flanges, etc.)—both factory and field—with a halide torch or electronic leak detector.

8. Replace all caps on service valves. Be sure they are

tight.

9. Check to be sure all tools and loose parts have been

removed from unit.

10. Check to be sure all panels, covers, and screws are in place.

11. Following initial inspection, start unit and: a. Check condenser fan and evaporator blower for

proper rotation.

b. Adjust furnace or evaporator blower for proper air

flow (approximately 400 cfm/ton).

c. Check fine and low voltage. (Should be within oper

ating voltage range stamped on unit rating plate.)

d. Check unit for proper operating refrigerant charge.

(See unit head pressure charging chart.)

e. Check compressor current draw in eunps.

f. Check unit for excessive noise, refrigerant tubing

for excessive vibration and for contact with other parts. Correct as necessary.

g. Do not leave installation until unit has been

observed through one or two complete cycles. Make

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certain at this time ail components are operating in correct sequence.

12. Thoroughly explain to owner(s): a. Operation of air conditioning system (thermostat,

reset controls, etc.).

b. Care and maintenance instructions (cleaning air fil

ters, condenser and evaporator coils, blower wheel.

and lubrication of all motors and blower bearings).

c. Factory and dealer warranties and how to obtain

service, if necessary.

d. Leave copy of Owner’s Manual with customer after

you have completed necessary information in Owner’s Manual.

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Page 12

38GP-C12SI-CIC

Supersedes 38GP-C10SI-CIC

Carrier International

Corporation ■ number one

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligation.

Printed in U.S.A.

air conditioninq maker

10/86 003-811