Carrier 38EC User Manual

Number One
Air Conditbninq
Maker

Installation, Start-Up ^ ^ 3

Division of

and Service Instructions

Carrier Corporation
Carrier Parkway • Syracuse

SAFETY CONSIDERATIONS
INSTALLATION

Step 1 — Check Equipment and

Jobsite.................................................................1

• UNPACK UNIT

• INSPECT EQUIPMENT

• COMPLETE OR CONSIDER

Step 2 — Make Piping Connections .... 2

• REPLACE THE ACCURATER™

• CONNECT REFRIGERANT LINES

Step 3 — Make Electrical

Connections........................................................5

• INSTALL A BRANCH CIRCUIT

• ROUTE LINE POWER LEADS INTO

• CONNECT GROUND LEAD AND

• CONNECT CONTROL POWER

START-UP

SERVICE.................................................................. 8-10

MAINTENANCE

Installation and servicing of air conditioning
equipment can be hazardous due to system pressure
and electrical components. Only trained and quali
fied service personnel should install, repair or
service air conditioning equipment.

Untrained personnel can perform basic mainten
ance functions of cleaning coils and filters and re

placing filters. All other operations should be
performed by trained service personnel. When
working on air conditioning equipment, observe
precautions in the literature, tags and labels attached
to the unit and other safety precautions that may

apply.

Follow all safety codes. Wear safety glasses and

work gloves. Use quenching cloth for brazing opera-

f N Y 13221

Air-Cooled Condensing Units

INDEX

..................................

.......................................................

SYSTEM REQUIREMENTS

REFRIGERANT CONTROL
PISTON IN THE INDOOR
COIL IF REQUIRED

DISCONNECT PER NEC

UNIT

POWER WIRING

WIRING

...............................................................

......................................................

SAFETY CONSIDERATIONS

Page

1

1-5

6-8

10-12

tions. Have fire extinguisher available for all brazing

operations.

WARJ^iKG; Before performitsg $ervice or
maiatesjaBce operatjojjs vam off

nsBiirt po’»er swiich. to indoor »nfi and outdoor

unit. Turn, off accessory heater poTser switch if
applicable- Electrical siioolc could cause per­sortal irgnry.

Table 1 — Physical Data (Refer to Fig. 1.)

MODEL 38EC
OPER WT (lb)
DIMENSlbNS (ft-in.)

Diameter A

Height B

CONNECTIONS (in.)

Suction (DDF)

Liquid (DDF)

REFRIG LINES

Suction (in DDF)

Liquid (in DDF)

*Fora1-1/8in suction line on 38EC048,060, a 3/4-in x 1-1/8 in suction

valve connection adapter is available as an accessory See Table 3

018 024

116 130 137 165

2-2-3/8 1 2-8

INSTALLATION

Step 1 — Check Equipment and Jobsite

UNPACK UNIT — Move to final location. Slide

from carton taking special care not to damage serv

ice valves or grilles.

INSPECT EQUIPMENT — File claim with ship

ping company if damaged or incomplete.
COMPLETE OR CONSIDER SYSTEM RE

QUIREMENTS before installation:

Consult local building codes and National Elec

trical Code (NEC) for special installation

requirements.

When installing, allow sufficient space for airflow

clearance, wiring, refrigerant piping and service.

Maintain a minimum of 4 ft clearance from obstruc
tions above and 18 in. on sides of unit. Maintain a
distance of 24 in. between condensing units. Posi
tion so water from roof or eaves does not flow

directly on unit.

Install on a solid, level mounting pad. It is not

necessary to attach unit to pad but if desired or

required by local code, position tiedown bolts in
pad. Fasten unit to pad using 2 holes provided in unit
base. See Fig. 1.

030 036 042 048* 060*

212 230

18|

1-9-3/4

5/8 3/4*

Recommended Field-Supplied Sizes

5/8 1 3/4 I 7/8 I 1-1/8

2-5-1/4

2-2-3/8 1 2-8 1 3-2

3/8

3/S

© Carrier Corporation 1982

Form 38EC-2SI

4-0 OVERHEAD SPACE REQUIRED
FOR SERVICE AND AIRFLOW

LIQUID VALVE SERVICE PORT

CONDENSER AIRFLOW

liDIAM HOLE

FOR POWER
WIRING

r-6 AIRFLOW
AND SERVICE

CLEARANCE

SUCTION VALVE SERVICE PORT

orator i^^if^field replacement of piston. Refer to
Table 2. Replace piston, if required, before connect
ing refrigerant lines. Piston replacement instructions
are ineluded in evaporator installation book. After
system installation is complete, use Charging Chart
to check and/or adjust refrigerant charge.

Condensing Units Connected to Carrier-Approved

Evaporators — Condensing units contain correct

system refrigerant charge for operation with evap

orator of the same size when connected by 25 ft
of field-supplied or Carrier accessory tubing.
Check refrigerant charge for maximum efficiency
(see Refrigerant Charging, page 6).

Table 2 — Optimization Chart

(Outdoor air design temperature. db-F.

100 F and below)

COND

UNIT

38EC

018
024
030
036
042
048
060

014 018

—

— —
—
— —

— —
— — —

—

Factory-installed piston Obtain replacement pistons thru
local Carrier distributor

ACCURATER™ piSTON NO.

Evap Size (Coil or Fan Coil)

024 030

46

—

—

TXV

52
SS

—

— —
—

—

57
63

— — ■■■■
— —

036

—

TXV

65

67

- -

042

048 060

— —

— — —

_

TXV

70

TXV

76 78

—

S3 82

— ■ ; 64

—

—

TXV

*CONCRETE PAD SHOULD WEIGH I5 TO 2 TIMES WEIGHT OF UNIT

Certified dimension drawings available on request

Fig. 1 — Dimensions. Connections and

Mounting Pad (Refer to Table 1.)

Carrier Cooling System Capacity Optimization —
AccuRater™ (bypass type) refrigerant control, with

field-replaceable piston (see Fig. 2), is supplied on
evaporator. Use Optimization Chart, Table 2, to
find AecuRater piston size required for eondenser/
evaporator system being installed. Pistons are cor­reetly sized for an evaporator of the same capacity as
the condensing unit, so piston change is not neces
sary. Mix-matching of condensing unit with evap-

Fig. 2 — AccuRater (Bypass Type)

Components

■Step 2 — Make Piping Connections — Con

densing units may be conneeted to evaporator sec
tions using Carrier accessory tubing package (Table

3) or field-supplied tubing of refrigerant grade,
correct size and condition (Table 1). For tubing
requirements beyond 50 ft, obtain information from
local Carrier distributor.

WARNING if

ùt

If 1-1/8 in. tubing is used (38EC048,060), braze
it to theaecessory 1-1 / 8 x 3/4-in. suction eonnection
adapter (Carrier Part No. 28VQ900011) or to eor-

rectly sized field-supplied adapter, then make Com
patible Fitting connections.

Table 3 — Accessories

PART NO

HH01AD040
HH93AZ040

HH07AT170

Low-Voltage Control Honeywell Deluxe Thermostat
Thermostat Subbase

Low-Voltage Control

DESCRIPTION

&

HH07AT174
HH93AZ176

HH01AD042
HH93AZ042

HH01YA192
HH93YZ194

38GS900102 Indoor Fan Relay (Six HN61KJ210)
38GS900212
28VQ900011
09WQ036.060 Refrigerant-to-Water Heat Exchanger for Chilled Water Systems All

TUBING

PACKAGES

38LS958151
38LS958201
38LS958251
38LS958301
38LS958351
38LS958401
38LS958501

38LS934151
38LS934201
38LS934251
38LS934301
38LS934351 35 3/8
38LS934401

38LS934501
38LS978151

38LS978201

38LS978251
38LS978301
38LS978351
38LS978401
38LS978501

‘For maximum capacities, use suction line sizes recommended in

Table 1 Use of accessory tubing packages smaller than recom

mended may result in slight capacity loss (see Note 2)
tSuction line is insulated and has a 90 degree bend at one end
JFor 5/8-in evaporator connection, cut off 3/4-in end

Length

Honeywell Thermostat

Thermostat Subbase
Low-Voltage Control Honeywell Thermostat

Thermostat Subbase

Low-Voltage Control Grayson Thermostat

Thermostat Subbase

Low-Voltage Transformer (Six 38GS900091)

Twelve 3/4- x 1-1/8 in Connection Adapters

TUBING

Liquid

(ft)

15 3/8 3/8
20 3/8 3/8
25 3/8
30 5/16
35 5/16
40 5/16
50

15 3/8
20 3/8
25 3/8
30

40 3/8 3/8 3/4 3/4 3/4
50 3/8

15 3/8 3/8
20
25 3/8

30 3/8

35 3/8

40 3/8

50 3/8

OD

(in.)

1/4

3/8 3/8 3/4 3/4 3/4 030, 036

3/8 3/8 7/8 3/4

Tube End

OD (in.)

3/8
3/8 5/8
3/8 5/8
3/8 5/8 3/4t
3/8 5/8

3/8 3/4 3/4 3/4
3/8
3/8 3/4 3/4 3/4

3/8

3/8

3/8 7/8 3/4
3/8 7/8 3/4
3/8 7/8
3/8 7/8 3/4
3/8 7/8 3/4

*

Suctionf

OD

(in )

5/8
5/8 3/4t 5/8
5/8 3/4t 5/8

3/4

3/4 3/4 3/4

3/4
7/8

NOTES
1 Do not cut 3/8-in OD liquid lines to a length shorter than 10

feet Do not cut 5/1 6-or 1/4-in liquid line Do not cut 7/8-in
OD suction lines

2 Field-supplied 1-1/8 in suction line is recommended on

38EC048 and 060 If accessory tubing package is used, a

capacity reduction can result

Tube End

OD (in.)

Evap Cond

3/4t

3/4t 5/8
3/4t 5/8

3/4t

3/4 3/4

3/4

3/4

3/4 3/4

MODEL

38EC

All

048, 060

MODEL

38EC

5/8

018, 024

5/8
5/8

3/4
3/4

3/4
3/4
3/4

3/4
3/4

■ WAHNiKO' IK> HOI Et'RY LiNESETS. if
is for exsojaSod peraaisi. dint

ing vmtn westiher. rdVigoraoi may to
the cookr boiieii ssetioo catismg
sltsggisig m A sksn ruo of kss
3 Ci of Uoesei may in pousni but ihore mmi fee
a 6 m vetiicai rise lo ifee valve cotmociiona oo
tire condeosiog sale.

Isolate interconnecting tubing from framing and
ductwork or where tubing runs thru stud spaces, en
closed ceilings or pipe chases. Use isolation type

hanger (Fig. 3) since rigid fastening transmits pulsa

tions to structure, creating objectionable sound.

For maximum capacity on 38EC048 and 060 sys

tems use 1-1/8 in. suction line. A capacity reduction
results if Carrier accessory tubing is used on these

systems. (Example: When a 25-ft accessory tubing
package is used on a 38EC048 system, the smaller
suction line results in a 3% capacity reduction.)

Length of interconnecting tubing may necessitate

refrigerant charge adjustment. Follow special re

quirements described in Start-Up, Refrigerant

Charging, page 6. Do not use less than 10 ft of inter

connecting tubing. On Carrier accessory tubing

packages, do not cut 5/ 16-in. or 1/4-in. liquid line or
7/8-in. suction line. These tubing packages have
swaged ends that, if cut, will not fit into refrigerant
line fittings. Bend or coil excess tubing to fit.

Do not use damaged, undersized or contaminated
tubing. Always evacuate or purge evaporator coil
and tubing system. When purging, use field-supplied
refrigerant, not unit holding charge refrigerant.

When making tubing connections, be sure to pro

vide clearance at unit for electrical connections.

REPLACE THE ACCURATER™ REFRIG
ERANT CONTROL PISTON IN THE INDOOR

COIL, if required, before connecting refrigerant
lines. See Carrier Cooling System Capacity Optimi
zation, page 2.

CONNECT REFRIGERANT LINES to fittings on

eondensing unit suction and liquid service valves

(Fig. 1). Unit Compatible Fittings permit mechanical

(quick connect) or sweat connections.

Model 38EC048,060 — When using 1 -1 / 8 in. field­supplied suction line, use accessory suction line
adapter. Braze refrigerant suction line to 1-1/8 in.
end of adapter. Allow adapter to cool before insert
ing into valve. Do not allow heat to reach valve as

O-ring damage may result. Connect 3/4-in. end of
adapter to unit suetion line Compatible Fitting.

Connect liquid refrigerant line to unit. If a 7/8-in.
field-supplied suction line is used, provide a field­supplied 3/ 4-in. to 7/ 8-in. suction line adapter. (Not

necessary if 38LS accessory tubing is used.)

Mechanical Connection — (Mate one set of connec

tions at a time.)

1. Loosen nut on Compatible Fitting one turn. Do
not remove.

2. Remove plug and be sure O-ring is in the groove
inside the Compatible Fitting.

3. Cut tubing to correct length. Deburr tubing.

4. Insert tube into Compatible Fitting until it
bottoms. Keep tube bottomed in Compatible

Fitting while tightening nut. Tighten nut until it

bottoms on shoulder of fitting or valve.

Sweat Connection or Repair — (Use refrigerant

grade tubing.)

1. Remove locking nut, rubber O-ring and Schrader
core and cap from valve service port.

2. Cut tubing to correct length. Deburr tubing.

3. Insert tube in Compatible Fitting until it bottoms.

Wrap top and bottom of service valves in wet
cloth to prevent damage by heat. Solder with low­temperature (430 F) solder.

4. Replace Schrader core and cap.

5. Evacuate or purge system using field-supplied

refrigerant.

f

Table 4 — Electrical Data (60 Hz)

COND

UNIT

38EC

018300 41 9 1 14
024300 59 13 3
030300

036300
042310 108
048300

048310
060300

030500 60
036500 74 11 7 12

042510
048500
048510 80 163

060500 136
036600

042610
048600
048610 40 8 1
060600 49

AWG — American \A/ire Gage

FLA — Full Load Amps
HACR — Heating, Air Conditioning and Refrigeration
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
RLA — Rated Load Amps

‘Permissible limits of the voltage range at which the unit will

operate satisfactorily

fCopper wire sizes based on 60C Use copper or copper-clad

aluminum wire only Use latest NEC for copper-clad aluminum
conductor sizing

V/PH

208-230/1

230/1

208-230/3

460/3

OPER

VOLTAGE*
Max

Min

254

197

254 207

254

197

506 414

Compressor Fan Min Wire

LRA RLA

69 16.2 10
93

145
105

22 9
35 3

150

74

120

41 5 9

38 6 5
60 74 1 2

FLA

Size (AWG)t

1 2 12

20 2
21 7
25 7

20 8

20

94 1 2

120

20

148

20 4

102 12

BRANCH CIRCUIT

Max Wire

(ft)

31 5 14 20
32 7 12 30

46.0 10 35

10

8
8

6

14

12
10
10
10

14 106 9 14 15
14 98 9 14 15
14 87 6 14 15
12

^Required when using nonmetallic conduit

“Maximum dual element size

NOTES

1 Fan motors are 230 v, single phase
2 All units have 24-v control circuit which requires external

power source

35 7
49 9

44.8 8 60 34.5

41 0
51 3

35 3 14 20

40 7
42 9
55 0

50 4
41 2

129 2 12 20 11 3

97 9

Min Gnd

Wire Size}

10

8

10

6

12
12
10
10 35

10

12

Max Fuse or

HACR Type

Ckt Bkr Amps“

45
50 29 5

50
60

25
25
30

45

25 14 9

MCA

12 6
17 8

21.5
27 7

31 0
46 5

13 0
16 6

17 0

20 9

22 8
27 9

8 6
9 3

105

Step 3 — Make Electrical Connections — Be

sure field wiring complies with local and national
fire, safety and electrical codes, and that voltage to
unit is within limits shown in Table 4. Contact local
power company for correction of improper line
voltage.

See Tafek 4 ««t »pply i

See Table 4 for recommended wire and fuse sizes.
When making electric connections, provide clear
ance at unit for refrigerant piping connections.

INSTALL A BRANCH CIRCUIT DISCONNECT
PER NEC of adequate size to handle unit starting

current. Locate disconnect within sight from and

readily accessible from the unit, per section 440-14
of National Electrical Code (NEC).

ROUTE LINE POWER LEADS INTO UNIT —
Extend leads from disconnect thru power wiring
hole provided (see Fig. 1) and into unit splice area.
Remove top cover to gain access to unit wiring.

CONNECT GROUND LEAD AND POWER
WIRING — Connect ground lead to a ground lug
in control box for safety. Then connect power wiring.
See Fig. 4. Splice line power leads to yellow and
black pigtails. Use wire nuts and tape at each con
nection. Connect unit wiring to copper or copper­clad aluminum power wiring. Do not connect to
aluminum wiring.

CONNECT CONTROE POWER WIRING —

Route 24-v control wires thru control wiring hole

and connect to pigtails supplied with unit (Fig. 1).

Use furnace or fan coil transformer as 24-v (40-va
minimum) supply for system as shown in Fig. 5, or
use accessory transformer shown in Table 3.

THERMOSTAT SUBBASE
HH93AZ042 OR

THERMOSTAT SUBBASE

HH93AZ042 OR

ARRANGEMENT B-ONE TRANSFORMER
(COOLING AND ONE-STAGE HEATING)

THERMOSTAT SUBBASE

HH93AZI76

_LEAVE JUMPER ON

SUBBASE (RH TORO

38EC

5»^ « £ K

MWk MW Mb •! t MV< VWWWM

iifscomiz^

PER

~ -«ROtiRtS V.E&0 ' UJS

MVWT

--

------

ftmwifvni

Fig. 4 — Line Power Connections

__

o

Eili&SS

tsam UNIT

CiMi ìmr

____

^

1

r

_L_

TO IFM LINE

VOLTAGE
POWER
SUPPLY

ARRANGEMENT C-ONE TRANSFORMER
(COOLING AND TWO-STAGE HEATING)

IFR, FS and IFM are located in furnace on heating-cooling
applications If accessory IFR is required for cooling-only
applications, locate IFR in fan coil

c

— Contactor (12-va) Trans — Transformer
— Fan Switch __

FS
HC

— Heating Control v-V Field Splice

IFM — Indoor Fan Motor
IFR

"Connect FS to low-speed indoor fan terminal when 2-speed fan

NOTE Refer to unit wiring label for wire colors C to G and C to Y
connections

Indoor Fan Relay

is used

1 1
1 !

1
1

L

1

ITRWS

HC|

-HC2
FURNACE

________
_________ Factory Wiring

Field Wiring

^ Fig. 5 — Control Circuit Connections

START-UP

1. Backseat (open) liquid and suction line service
valves. Open liquid line first to equalize pres
sure and reduce oil flow to suction line.

2. Set thermostat selector switch at OFF.

3. Set room thermostat at desired temperature.

Be sure this temperature is below indoor ambient.

4. Close electrical disconnects energizing entire
system.

5. Set room thermostat at COOL and fan switch at
FAN or AUTO, as desired. Operate unit for 15

minutes; then check system refrigerant charge.

See Refrigerant Charging, discussed later.

Motors and controls are designed to operate satis

factorily in the voltage range shown in Table 4. If

necessary to use manifold gages for servicing, refer

to Carrier Standard Service Techniques Manual,

Chapter 1, Refrigerants, page 1-5, Fig. 8 for bypass
method of returning charge to system. Removal of
liquid line charging hose without following these
precautions could result in some loss of charge.

Refrigerant Charging

ca» саяш flooding.

Table 5 — Service Data

UNIT

38EC

018 3 3
024
030 5 3
036 7.5

042 63
048300 6 1
048310

060

‘Factory refrigerant charge is adequate when evaporator and con

densing unit are the same size and are connected with 25 ft or less
of field-supplied tubing of recommended size or Carrier accessory
tubing

R-22 CHG*

(lb)

3 3 1110/950

72

9 6

CONDENSER

FAN RPM (Hi/Lo)

1075/950

Condensing units contain correct operating

charge for complete system when connected to

Carrier-approved evaporators of same capacity as
condensing unit with 25 ft or less of Carrier accessory
tubing or field-supplied tubing of recommended

size. For every 10 ft of liquid line of recommended

size over 25 ft, add refrigerant charge as follows: .41b

for 3/8-in. line; .28 lb for 5/ 16-in. line. On all other

systems, adjust eharge for correct operation as

applicable.

Service port eonnections are provided on liquid
and suction line service valves for evacuation and
charging. See Fig. 1.

TO CHECK, ADJUST OR REPLACE REFRIG
ERANT CHARGE use method recommended in
Table 6. Details of charging methods are listed
below.

Before recharging system, thoroughly evacuate
system and then weigh in refrigerant charge speci
fied in Table 5. Check or adjust charge as required.

Refer to Carrier Standard Service Techniques
Manual, Chapter 1, Refrigerants, for additional sys

tem evacuation and dehydration instructions.

WEIGHT METHOD — Refer to Table 5 or unit
nameplate for correct system refrigerant charge.

Remove any refrigerant remaining in system before

recharging.

When system is not evacuated, subtract the
following amount from total charge.

38EC018 thru 030 — .10 lb (1.6 oz)
38EC036 thru 060 — .20 lb (3.2 oz)

The Dial-a-charge charging cylinder is an accu
rate device used to recharge system by weight. These
cylinders are available at refrigeration supply firms.

CHARGING CHART METHOD — Use Charging
Chart, Fig. 6, and the following procedure.

1. Operate unit a minimum of 10 minutes before
checking charge.

Measure suction pressure by attaching a gage to

2.

suction valve service port.

Measure suction line temperature by attaching a

3.
service thermometer to unit suction line near suc
tion valve. Insulate bulb, thermocouple or
thermistor for accurate reading.

f:

Table 6 — Refrigerant Charging Methods

roNniilMlT ADJUSTING CHARGE

ALL 1 or

‘Sight glass field supplied and installed in liquid refrigerant line

I METHODS OF CHECKING OR

38EC 1 System Refrigerant Control

1 Non TXV TXV
1 Chargemaster®

1 Charging Chart

Sight

Glass*

METHODS FOR COMPLETE

System Refrigerant Control

Non TXV

Weight Method

plus

Chargemaster or

Charging Chart

RECHARGING

TXV

Weight Method

plus

Sight Glass*

(AccuRater™ System)

4. Measure outdoor (condenser inlet) air dry-bulb
temperature with a second thermometer.

5. Refer to Charging Chart (Fig. 6). Find air tem
perature entering condenser and project hori
zontally to curve showing suction pressure (psig
at suction valve).

6. From this intersection, project vertically down
ward to suction line temperature.

7. If unit has a higher suction line temperature than
charted temperature, add refrigerant until
charted temperature is reached.

If unit has a lower suction line temperature than

8.

charted temperature, bleed refrigerant until
charted temperature is reached.

If air temperature entering condenser or pressure

9.

at suction valve changes, charge to new suction
line temperature indicated on chart.

CHARGEMASTER® METHOD — Operate unit

for 10 minutes before using Chargemaster (Carrier

Part No. 38GC680004).

1. Tape Chargemaster feeler bulb to suction line
close to condensing unit. Insulate bulb. Ensure
suction line is clean for good contact with bulb.
(Uninsulated bulb or dirty suction line will seri
ously affect accuracy of temperature readings.)

2. Connect refrigerant drum to Chargemaster inlet
port keeping drum in position for vapor charging.

3. Connect Chargemaster outlet port to unit suction
valve service port.

4. Crack valves on refrigerant drum and Charge­master to purge lines from drum to suction valve.

After purging lines, close valve on Chargemaster
only.

5. Measure outdoor air dry-bulb temperature.

6. Crack unit suction valve and read evaporator

temperature at red needle position on Charge­master temperature gage and suction line tem
perature at black needle position.

Enter Chargemaster Charging Chart, Table 7, at

7.
outdoor air temperature (step 5) and evaporator
temperature (step 6). Find the suction line tem
perature required for correct system charge. If
actual suction line temperature (step 6) is higher
than table value, the system is undercharged. If
suction line temperature is lower than table

value, system is overcharged.

EXAMPLE: At outdoor air temperature of 84 F
and evaporator temperature of 43 F, the system
will be correctly charged at 76 F ± 2 F suction

line temperature. See Table 7.

Add charge by slowly opening Chargemaster

valve. If necessary, reduce charge by bleeding at

liquid line service valve. Check outdoor air and

evaporator temperature during procedure. If they

change, refer back to Chargemaster Charging

Chart.

Table 7 — 38EC Chargemaster Charging

Chart (AccuRater System)

OUTDOOR

TEMP

(F)

60
62 30
64 28
66
68 34 43
70 32 41 52
72
74
76
78

80 26
82

m 3Î

86
88 35
90 34
92
94
96 38
98 36

too 42 49 57 65 75

102
104
106
108 43 49
110 41 47 55 63
112
114

Example

EVAPORATOR TEMPERATURE (F)

21

32

27

25 28 31

Suction Line Temperature (F)

40 51
38 39
37 47;
35 45 : 57

31 39 50

37 : 48

30

36 46

29
27 35

33 42
32

29 37

34

60

54 67

44

40

mr

im m

33

37 40 45 48

64
61 72
58

69

56

66

54

63

52

61 72

50

59 68

46

55 63 73 85

44

53 61 70

42

51 59

41

49 57 65

39 47 55

45 53
44 51 59 67

41
39

75

X4£^:«:

48
46
45 51

; ^

81
78 90

68

75

63

72

61

70

55 63 73

61

53

59
57

46 53

50

86
83
80
77

70
68
65

61
59

Correct use of Chargemaster ensures that an opti
mum refrigerant charge will be in system when con
ditions and system components are normal.
However, the Chargemaster does not solve or fix
system abnormalities. It indicates correct charge for
condition of the system. It will not make corrections
for dirty filters, slow fans, excessively long or short
suction lines or other abnormal conditions. This
charging device ensures that a correct relationship
exists between outdoor temperature, evaporator

temperature, and suction line temperature on a spe

cific system.

SIGHT GLASS METHOD — (Field-supplied sight
glass installed in liquid line.) A satisfactory oper
ating charge can be obtained on thermal expansion

valve systems only by charging to a clear sight glass.
For optimum charge, increase high-side pressure to

380 ± 10 psig by blocking condenser fan discharge

or air entering condenser. Charge to a clear sight

glass while holding constant high-side pressure. For

peak efficiency, adjust charge to yield a liquid refrig
erant temperature at the evaporator that is approxi
mately the same as outdoor dry-bulb temperature.

CRANKCASE HEATER SWITCH

SUCTION LINE

LOW
PRESSURE
SWITCH

DISCHARGE GRILLE (FAN
MOTOR UNDERNEATH) ^

WIRE ACCESS OPENING
TOP COVER-

HOT GAS
DISCHARGE LINE

CONDENSER COIL

COMPRESSOR

HIGH-

'/ PRESSURE

SWITCH

FAN MOTOR
AND
COMPRESSOR
LEADS

PLASTIC PIN
OF TUBE

lì SUPPORT

SERVICE

Compressor Removal — See Table 8 for com

pressor information and Fig. 7 for component loca
tion. Shut off power to unit. Remove refrigerant
from unit using refrigerant removal methods de
scribed in Carrier Standard Service Techniques

Manual, Chapter 1, Refrigerants. Be sure system
pressure is 0 psig before attempting eompressor
removal.

^ Table 8 — Compressor Data

UNIT PRODUCTION

38EC

018300 AJ8520G
024300
030300 CRF1-0250PFV Ì;
036300 CRJ1-0300PFV 55
042310
048300
048310
060300 PC6416AG
030500
036500
042510
048500 YRD6-0400-TFC
048510

060500
036600
042610
048600
048610
060600

'Refer to Carrier Service Parts Catalog for replacement model

numbers

tWhere piping exceeds 50ft, obtain information from local Carrier

distributor

COMPR*

CRD-0200PFV 55

AV5542E 54

YRD-0400-PFV 72

PC5016BD 66

CRF1-0250-TF5

CRJ1-0300-TF5 55

AV5542E

PY5016BD 66
PY6416AF 66
CRJ1-0300-TFD 55

AV5542E

YRD6-0400-FFD 72 68
PH5016BD
PH6416AF 66 62

OIL CHARGE (oz)t

Initial Recharge

26

55

66
55

54
72

54

66 62

24
51
51
51
50
68
62
62
51
51

50
68
62
62

51

50

Fig. 7 — Condensing Unit 38EC

Component Locations

Follow safety codes. Wear safety glasses and

work gloves. Have quenching cloth available.

CAilTIOMi
m iufeisjg or doroags tmy

1. Remove top cover: remove 3 screws holding
top cover to connector plate; remove third screw
clockwise from connector plate; loosen remain
ing 5 screws; lift cover straight up.

2. Disconnect high- and low-voltage field wiring
and fan motor leads from capacitor and
contactor.

3. Remove 4 screws (38FC018 thru 030) or 8 screws
(38FC036 thru 060) holding discharge grille in
place. Lift grille from unit.

4. Disconnect compressor leads (crankcase heater,
low-pressure switch, if so equipped) from elec
trical components and pull them thru the wire
access opening into the coil section. Lift fan

orifice/control ring after pinching and pressing

down on 3 plastic pins of tube supports.

5. Remove louvered casing by taking out 16 screws
securing it to the cabinet and sliding it away
from the coil.

6. Using a midget tubing cutter, cut liquid and
discharge lines on the coil and suction line at a
convenient place for easy reassembly with
copper slip couplings.

After plugging connections, remove condenser
coil by pinching plastic pins of tube supports
that extend into basepan and lift vertically. Set
coil on a clean, flat surface.

Remove compressor holddown bolts and slide

8.

out compressor. Remove crankcase heater, if

so equipped.

9. Carefully unbraze suction and discharge line
piping stubs from compressor after noting posi
tion of stubs to assist when reinstalling.

10. Install new compressor, placing crankcase
heater around compressor, if so equipped. Be
sure compressor holddown bolts are in place.

11. Replace coil; braze suction and discharge lines
to compressor piping stubs (at points where eut.

Step 6); rewire compressor and leak test.

12. Replace fan orifice/control ring; connect com
pressor wires after feeding them thru eontrol
ring; replace fan/grille assembly and rewire;
connect high- and low-voltage power wiring;
and replace louvered casing.

13. Replace top cover by running screws into orifice
loosely and tighten when cover is in plaee.

14. Evacuate and reeharge system.

Filter Drier — Install field-supplied filter drier

(Table 3) in system liquid line when refrigerant

system is opened for serviee as described under
Compressor Removal. Position drier in liquid line

at convenient loeation.

Pumpdown Procedure — The system may be

pumped down in order to make repairs on low side
without losing eomplete refrigerant charge.

1. Attach pressure gage to suction service valve gage
port.

2. Frontseat the liquid line service valve.

3. Start unit and run until suction pressure reaches
5 psig (see Caution).

4. Shut unit off and frontseat suction valve.

5. Vent remaining pressure to atmosphere.

1

Unit Controls and Safety Devices

HIGH-PRESSURE RELIEF VALVE is located in
eompressor. Relief valve opens if system operating
pressure differential between suction and discharge
pressure reaches 400 to 500 psi on all models.

LOW-PRESSURE SWITCH is located on unit

suction line. Low-pressure switch settings are: cut

out, 31 ± 4 psig; cut-in, 60 (+15, -0) psig.

INTERNAL TEMPERATURE AND/OR CUR
RENT SENSITIVE OVERLOADS reset automati

cally when motor internal temperatures drop to a

safe level (overload may require up to 30 minutes to
reset). When internal overload is suspected of being
open, check by using an ohmmeter or continuity
tester. If neeessary, refer to Carrier Standard Serv
ice Techniques Manual, Chapter 2, Eleetrical, for
complete instructions.

INHERENT FAN MOTOR PROTECTION pro

tects motor from abnormal current and temperature.

FAN SWITCH changes to high speed at 90 F ± 5;

changes to low speed at 75 F ± 5.

SOLID-STATE TIME GUARD II CIRCUIT,
if so equipped, protects unit compressor by prevent
ing short cycling. Time Guard II circuit provides a
5 ± 2-minute delay before restarting compressor
after shutdown for any reason. On normal start-up,
the 5-minute delay occurs before thermostat closes.
After thermostat closes, the Time Guard 11 circuit
then provides a 3-second delay to prevent contactor
chattering.

CRANKCASE HEATER keeps the crankcase
warm during the off cycle and thus prevents dilution
of the oil with refrigerant. This assures good lubriea­tion and prevents loss of oil from crankcase during
start-up.

CRANKCASE HEATER SWITCH (relay for 060,

3-ph, 460-v units only) deaetivates heater when
compressor is operating for maximum energy
efficiency.

START CAPACITOR AND RELAY assure

proper compressor start-up under adverse

conditions.

Compatible Fitting Repair

MECHANICAL CONNECTION — Frontseat unit

service valves. Relieve refrigerant pressure from
tubing. Back off locknut from Compatible Fitting
onto tube. Cut fitting between threads and 0-ring
as shown in Fig. 8. Remove tubing section

remaining in threaded portion of fitting. Discard

locknut.

Clean, flux, and insert new tube end into remain
ing portion of Compatible Fitting. Wrap valve in
wet rag. Heat and apply low-temperature (430 F)
solder. Do not overheat valve.

Evacuate or purge evaporator coil and tubing
system. Add refrigerant charge. See Refrigerant
Charging instructions described previously.

Fig. 8 — Repair of Mechanical Connection

Lubrication

■COMPRESSOR contains factory oil charge. Re
place oil when lost. See Table 8 for oil recharge and
refer to Carrier Standard Service Techniques

Manual, Chapter 1, page 1-21, for oil recharg
ing procedure. Use Carrier PP33-1, Texaco WFl-32
or Suniso 3GS oil.

FAN MOTOR BEARINGS are prelubricated for 3
years heavy duty or 5 years normal duty. When
lubrication is necessary, send motor to authorized

motor repair shop.

^Coil Repair — A flare-union coupling repair kit

is available, with instructions, thru Carrier Service

Parts.

Coil Cleaning to be done at the beginning of

each cooling season or more often if required.

Condenser Fan Adjustment — Required fan

position is shown in Fig. 9. Adjust fan by loosening
setscrew(s) and moving fan blade up or down.

Fig. 9 — Condenser Fan Position

Condenser Fan Motor Removal

1. Shut off power to unit. Failure to do so may
result in electric shock or injury from rotating fan
blade.

2. Remove top cover, referring to Compressor
Removal, step 1.

3. Disconnect fan motor leads from control leads.

See Fig. 7.

4. Remove 4 screws (38EC018 thru 030) or 8 screws

(38EC036 thru 060) holding fan motor/discharge
grille in place and lift assembly from unit.

5. Remove Carrier nameplate by straightening
tabs.

6. Remove 4 nuts holding fan motor to discharge
grille. Remove motor and leads.

7. Reassembly is reverse of above procedure. Make

sure fan is positioned correctly as in Fig. 9.

1. Shut off power to unit.

2. Remove louvered casing by taking out 16 screws
securing it to the cabinet and sliding it away from
the coil.

3. Clean coil using vacuum cleaner and its crevice
tool (see Fig. 10). Work crevice tool vertically
making sure tool only touches dirt on fins. To
prevent fm removal, do not “scrub” fins with tool
or move tool horizontally.

4. If oil deposits are present, spray coil with house
hold detergent (Fantastic, Lestoil, 409, or any
similar type). Wait 10 minutes then proceed to
step 5.

Fig. 10 — Crevice Cleaning Tool

10

5. Using garden hose, spray coil vertically down
ward with a constant stream of water at moderate
pressure (see Fig. 11). Keep nozzle at a 15 to 20
degree angle, about 3 in. from coil face and 18 in.
from tube. Spray so debris is washed out and
away from coil.

6. Reinstall louvered casing being careful not to
damage coil.

7. Restore power to unit.

TROUBLESHOOTING GUIDE

SYMPTOM AND

PROBABLE CAUSE

COMPRESSOR SHUTS OFF. FAN OVERLOAD
OR HIGH-PRESSURE SWITCH CUT OUT, OR
INTERNAL PRESSURE RELIEF OPENS

Condenser Fan On

1. Condenser air restricted or recirculating.

2. Refrigerant overcharge, noncondensables in

system; system restricted.

3. Improper line voltage, loose electrical connec
tions, faulty run capacitor.

Condenser Fan Off

1. Fan slipping on shaft, fan motor bearing stuck,

fan motor defective.

2. Loose electrical connections. Fan motor over

load open.

COMPRESSOR RUNS BUT COOLING IS INSUFFICIENT

1. Low refrigerant charge.

2. Dirty filters, partially restricted airflow (evap
orator coil may be partially iced).

High Suction Pressure

1. Defective compressor valves (accompanied by

low head pressure).

COMPRESSOR SHUTS OFF FROM LOW-PRESSURE SWITCH CUTOUT

Evaporator Fan Runs

1. Low refrigerant charge or restricted evaporator

air.

2. Restricted refrigerant flow.

Evaporator Fan Stopped

1. Evaporator fan-motor defective or inoperative

COMPRESSOR SHUTS OFF WILL NOT RESTART

Contactor Open

1. Burned out transformer, open thermostat circuit,

faulty control relay, open overload

Contactor Closed or Closes Then Opens

1. Compressor power is out, compressor motor is
burned out or internal overloads are open. Time
Guard II circuit faulty.

PROBABLE REMEDY

1. Condenser coil blocked. See Maintenance, Coil

Cleaning. Check airflow clearance (Fig.‘ 1)

2. Review Refrigerant Charging procedures; purge
system, replace filter drier, check refrigerant
control.

3. Review Installation, Step 3; replace capacitor.

1. Tighten fan hub setscrews, see Condenser Fan

Motor Removal.

2. Check unit wiring. Check motor bearings. Re

place motor.

1. Check Refrigerant Charging procedures.

2. Check evaporator air system for dirty filters,
obstruction in ductwork, improper damper
settings. Refer to coil, fan coil or furnace

instructions as applicable.

1. Perform Compressor Replacement procedure.

Recheck system charge.

1. See Compressor Runs But Cooling Is Insufficient

above regarding filters, ductwork, etc

2. Check refrigerant flow device, be sure correct

AccuRaterTf^ or TXV is used.

Check furnace or fan instructions regarding de
fective fan relay, belt adjustment, condition of
motor bearings and overloads, check and tighten
electrical connections, check power supply.

Check control circuit components and wiring.

Refer to unit label diagram, check all conditions.
Refer to Standard System Techniques Manual,
Chapter 2, Electrical.

Check main power supply wiring. Refer to Elec

trical Data table and label diagram. Substitute
Time Guard II with a replacement to verify its

operation. Refer to Standard Service Techniques
Manual, Chapter 2, Electrical.

For replacement items use Carrier Specified Parts

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

Book

Tab

1 4

3a 2a

Form 38EC-2SI Supersedes 38EC-1 SI

Printed in U S A 6-82

PC 101 Catalog No 533-848