Carrier 38QN User Manual

38QN

HEATING & COOLING

Heat Pumps—Outdoor Section

Installation and Start-Up Instructions

SAFETY CONSIDERATIONS

Installing and servicing air conditioning equipment can be
hazardous due to system pressure and electrical compo
nents. Only trained and qualified service personnel should
install or service air conditioning equipment.

Untrained personnel can perform basic maintenance, such

as cleaning and replacing filters. All other operations should
be performed by trained service personnel. When working
on air conditioning equipment, observe precautions in litera
ture and on tags emd labels attached to unit.

Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for brazing operations. Have
fire extinguisher available. Read these instructions thor
oughly. Consult local building codes and National Electrical
Code (NEC) for special installation requirements.

A WARNING

Before installing or servicing unit, always turn off main
power to system. There may be more than one discon
nect switch. Turn off accessory heater power if applica
ble. Electrical shock can cause personal injury.

INSTALLATION

Step 1—Check Equipment and Jobsite—Install on a sohd,

level mounting pad. It is recommended that unit be
attached to pad using tiedown bolts. Fasten unit to pad

using holes provided in unit mounting feet. See Fig. 1.

A87150

Dimensions (ft-in.)

AIRFLOW

A86167

r-6" AIRFLOW AND
SERVICE CLEARANCE
AROUND UNIT — 12"
ON VALVE SIDE

Model 38QN 015-030 036-048 060
Diameters
Squares (minimum)

Tiedown Bolt
Locations C

1-9’2
1-11

0-6=4

D

1-4

E 0-9V

Fig. 1—Dimensions, Connections and Mounting Pad (Refer to Tabie 1)

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

Book| 1 I 4

Tab l5al5a

PC 101 Cataiog No. 533-820 Printed in U.S.A. Form 38QN-10Si 10-87 Pg 1 Repiaces: 38QN-9Si

2-5\ 3-3

2-6 3-4

0-9’'2

1-10^2

1-1

1-T=16

2-7

1-5^8

Table 1—Physical Data

MODEL 38QN

OPER WT (lb)* 132

REFRIGERANT

Control

CONDFAN

Air Discharge
AirQty(Cfm)
Mtr Rpm (60 Hz)

CONDCOIL(fins/in.)

Tube Diam
Rows
Refrig Ckts
Face Area (sq ft)

DIMENSIONS (ft-in.)

Diameter A
Height B

CONNECT, (in. ODF)

Suction

Liquid
REFRIG LINES
(in. ODF)

Suction

Liquid

♦Weight increases slightly with addition of any accessories.
t38QN048-060 require lYs-in. suction line for optimum perform

ance. A %- X 17s-in. connection adapter accessory (Carrier Part

No. 28AU900061) is available. If a 7s-in. accessory tubing pack

age is used, expect a slight capacity loss.

015 018

1850 1 2400 1 3100 1 3800 | 4000 | 5000

Compatible Fitting (Suction) & Flare (Liquid)

When installing, allow sufiBcient space for edrflow clearance,
wiring, refrigerant piping and servicing. Maintain a mini
mum of 4 ft clearance from obstructions above and 18 in.
around unit (12 in. on valve side). Maintedn a distance of 24
in. between heat pumps. Position so water or ice from roof
or eaves cannot fall directly on unit.

Step 2—Replace Indoor AccuRater™ Piston, if Required-

Check indoor cod piston to see if it matches the required pis
ton listed in Table 2. If it does not match, replace indoor cod
piston with piston shipped with this outdoor unit (located in

plastic bag taped to valves). See Fig. 2.

024

151 155 180 195

830 1 1075 850 | 1075 | 840

2 2

12.77

1-9%

% 1 %

%

030 036 042

1

Vertical

Vin.

22

1

%

%

6
E-Coil

AccuRater'^'^ (Bypass Type)

Propeller Type, Direct Drive

189 235 270

2 1 3 1

17.33

2-574

2-7

% 1%t

048 060

)

21.88
3-2%

Table 2—AccuRater™ Chart

OUTDOOR

UNIT

38QN

015 35 46
018 40
024
030 55 65
036
042 67 73
048 73 82
060

OUTDOOR

PISTON

46 59

61

78

INDOOR

PISTON

49

73

101

FLARE NUT

Step 3—Make Piping Connections—Outdoor units may be

connected to indoor sections using Carrier accessory tubing
package or field-supplied tubing of refrigerant grade, cor
rect size and condition (Table 1). For tubing requirements
beyond 50 ft, obtain information from local Carrier
distributor.

Outdoor Units Connected to Carrier-Approved Indoor
Units—Outdoor units contain correct system refrigerant

charge for operation with indoor unit of the same size when
connected by 25 ft of field-supplied or Carrier accessory tub

ing. Check refrigerant charge for maximum efficiency.

A CAUTION

DO NOT BURY MORE THAN 3 FT OF REFRIGER
ANT TUBING IN GROUND. If any section of tubing
is buried, there must be a 6-in. vertical rise to valve con
nections on outdoor unit. If more than the recom
mended length is buried, refrigerant may migrate to
cooler buried section during extended periods of unit
shutdown. This causes refrigerant slugging and possi
ble compressor damage at start-up.

CONNECT REFRIGERANT LINES to fittings on unit
suction and liquid service valves (Fig. 1). Liquid service

valve has flare fitting; suction service valve has Compatible

Fitting. Make suction line connection first. Slide flare nut

on liquid line, then flare and connect liquid line. Use a maxi
mum torque of 15 ft-lb to tighten flare nut. (Do not disas
semble AccuRater.) Unit Compatible Fitting permits
mechanical or sweat connection as described below.

Models 38QN048,060—When using iVs in. field-supplied
refrigerant suction line, sweat-connect suction line to lYs in.
end of required connection adapter. Be sure to provide a
heat sink at the service valve to prevent damage during
sweating operation. Connect %-in. end of adapter to unit suc
tion line Compatible Fitting. Connect liquid refrigerant line
to unit. When a 7s-in. field-supplied suction hne is used, pro
vide a field-supplied %-in. to 7s-in. suction line adapter (not
necessary if 38LS accessory tube is used).

NOTE: Compatible Fitting on outdoor section has alumi
num plug located beneath compatible nut on suction valve.
Plug keeps contaminants out of Compatible Fitting.

A CAUTION

When removing compatible nut, be careful pressure
build-up does not cause aluminum plug to blow and
cause personal injury. After tubing is hooked up, dis
card plug.

Mechanical Connection—Mate one set of connections at a
time.

1. Remove nut on Compatible Fitting.

2. Remove plug and be sure 0-ring is in the groove inside
the Compatible Fitting.

3. Cut tubing to correct length. Deburr and size as neces
sary. Slide nut onto tube.

4. Insert tube into Compatible Fitting until it bottoms.

Tighten nut until it bottoms on shoulder of fitting or
valve. Keep tube bottomed in Compatible Fitting while

tightening nut.

A87151

Fig. 2—AccuRater (Bypass Type) Components

A CAUTION

If undersized, damaged or eUipticaUy-shaped tubing is

used when making Compatible Fitting, leaks may

result.

Sweat Connection—Use refrigerant grade tubing.

1. Remove locking nut, plug, rubber 0-ring and Schrader
core and cap from valve service port.

2. Cut tubing to correct length. Deburr and size as
necessary.

3. Insert tube in Compatible Fitting until it bottoms.
NOTE: Wrap top and bottom of service valves in wet

cloth to prevent damage by heat. Solder with low­temperature (430 F) silver edloy solder.

4. Replace Schrader core and cap.

5. Evacuate or purge system with field-supplied

refrigerant.

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. See Fig. 3. Remove tubing sec
tion remaining in threaded portion of fitting. Discard
locknut.

COMPATIBLE FITTING

Clean, flux and insert new tube end into remaining portion
of Compatible Fitting. Wrap valve in wet rag to prevent
damaging factory-made joints. Heat and apply low-tempera
ture (430 F) solder.

SWEAT CONNECTION-Frontseat unit service valves.
Relieve refrigerant pressure from tubing. Clean and flux
around leak. Repair, using low-temperature (430 F) solder.
Evacuate or purge evaporator coil and tubing system. Add

refrigerant charge. See Refrigerant Charging.

Step 4—Make Electrical Connections—Be sure field wir

ing comphes with local and national fire, safety and electri
cal codes, and voltage to system is within limits shown in
Table 3. Contact local power company for correction of
improper fine voltage.

NOTE: Operation of unit on improper line voltage consti
tutes abuse and could affect Carrier warranty. See Table 3.

Do not install unit in system where voltage may fluctuate

above or below permissible limits.
See Table 3 for recommended fuse sizes. When making elec

trical connections, provide clearance at unit for refrigerant

piping connections.

INSTALL BRANCH CIRCUIT DISCONNECT PER NEC

of adequate size to handle unit starting current. Locate dis
connect within sight from and readily accessible from unit,
per Section 440-14 of National Electrical Code (NEC).

ROUTE LINE POWER LEADS-Extend leads from dis
connect through power wiring hole provided (see Fig. 1) and
into unit splice area. Remove control box cover to gain
access to unit wiring.

Fig. 3—-Repair of Mechanicai Connection

Tabie 3—Eiectricai Data (60 Hz)

Three-phase availabie with 036-060 sizes

OUTDOOR
UNIT 38QN

015-32
018-33 49.0
024-32 53.0

030-34 208-230/1 253 197 70.0
036-31
042-31 108.0
048-31 110.0
060-31

036-51 65.0 11.5 0.9 15.3
042-51
048-51 92.0 14.7 1.9 20.2

060-51 130.0 21.4 2.1
036-61

042-61 460/3 506 414
048-61 46.0 7.0 1.6 10.4
060-61 65.0 9.6 1.6 13.9

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

NOTE: Control circuit is 24 v on all units and requires external power source.

V/PH OPER VOLTS* COMPR

208/230/3

Max

254 187 80.0 13.3 2.5 19.1

Min

LRA

35.0

86.7

142.0 33.0

32.8

35.0

FAN

RLA

7.2

10.5

13.2

17.6 1.9

18.9

21.8

27.3

5.1 1.6 8.0

7.2 1.6 10.6

♦Permissible limits of the voltage range at which unit will operate

satisfactorily.

tTime-delay fuse.

FLA

0.7

0.7 13.8

2.1 18.6

0.9 24.5

2.6 29.9

1.9 36.0

2.1 43.4

MCA

9.7

24.1

28.9

MAX FUSEt OR

HACR TYPE

CKTBKRAMPS

15
20
30
40
40
50
60
60

25
30
30

, 45

15
15
15
20