Carrier 52C User Manual [en, es]

52C and 52P

52C

SERIES

SERIES

OWNER’S MANUAL

PACKAGED TERMINAL AIR CONDITIONERS

AND HEAT PUMPS

7,000-15,000 Btuh

CONTENTS

Page

GENERAL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

UNIT INSPECTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . .2,3

FRONT PANEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

ELECTRICAL DATA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

ALL UNITS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

VOLTAGE SUPPLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8

CHASSIS INSTALLATION . . . . . . . . . . . . . . . . . . . . . . 5

WA LL THERMOSTAT INSTALLATION. . . . . . . . . . . 8

OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9,10

COMFORT CONTROLS. . . . . . . . . . . . . . . . . . . . . . . . . 9

OPERATING CONTROLS. . . . . . . . . . . . . . . . . . . . . . 10

OPERATING MODES. . . . . . . . . . . . . . . . . . . . . . . . . . 10

Page

CARE AND MAINTENANCE . . . . . . . . . . . . . . . . . 11,12

INDOOR-AIR INLET FILTERS . . . . . . . . . . . . . . . . . . 11

EXTERNAL PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

INTERNAL PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

PREVENTATIVE MAINTENANCE. . . . . . . . . . . . . . . . 13

TROUBLESHOOTING. . . . . . . . . . . . . . . . . . . . . . . . . . . 14

ACCESSORIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

1•800•894•6449 (in USA and Canada)

For Service/Technical Assistance

1•800•830•8600 (Mexico)

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

Book 1 4
Ta b 9 a 1 1 a

PC 132 Catalog No. 535-20066 Printed in U.S.A. Form 52C,P-2SO Pg 1 10-04 Replaces: 52C,P-1SO

GENERAL

FIGURE 1 — SAMPLE DATA INFORMATION PLATE

Thank you for choosing Carrier! You can feel confident
in your selection because the same pride in craftsman­ship and engineering knowledge that goes into Carrier
equipment at the Astrodome in Texas, the Sistine
Chapel in Rome, the US Capitol Hall of Congress, and
thousands of other installations worldwide has gone
into the construction of this unit.

The Carrier package terminal air conditioners and
heat pumps provide a high standard of quality in per­formance, workmanship, durability and appearance as
they heat and cool the occupied air space year round.

This manual provides information for ease of installa­tion, operation and maintenance of the 52C and 52P
units. The following units are covered in this manual
(see Figure 1 for additional unit information):

52CE 60 Hz cooling with electric heat units
52CQ 60 Hz cooling, electric heat, and heat pump units
52PE 60 Hz cooling with electric heat units
52PQ 60 Hz cooling, electric heat, and heat pump units
52PC 60 Hz cooling only units

All models are designed for through-the-wall installa­tion. Separate installation instructions are included

MODEL 52PQA312301AA

SERIAL 3701X11520

DATE OF MFG. 09/12/2001

VOLT RANGE 187-253

VOLTS 230/208

PH 1

MIN CKT AMPACITY 19.3

R-22 OZ 34

DESIGN PSIG 350 HIGH SIDE, 150 LOW SIDE

BTU/HR 12,100/12,000

AMPS 4.8/5.3

WATTS 1100/1100

EER 11.0/10.9

COMP

FAN

MOTOR

BTU/HR 10,800/10,700

AMPS 15.6/14.5

WATTS 3570/2997

COP 3.2/3.2

HEATER

BTU/HR

USE

TIME DELAY FUSE

OR HACR TYPE

CIRCUIT BREAKER

HZ

COOLING

6.1

RLA

29

LRA

0.75

FLA

1/8

HP

HEATING

AMPS 14.8/13.7

WATTS 3400/2850

WATER

STEAM

CANADIAN INSTALLATION

AMP

20

MAX FUSE

60

AMP AMP

20

MAX BREAKER

20

with all accessory components. See Accessories section
on page 15 for complete listing of accessories.

UNIT INSPECTION

Examine unit for damage incurred during shipment.
File a claim immediately with the transit company if
damage is found.

The data information plate (Figure 1) lists the model
number, voltage ranges, and other important electrical
information about this product. Reading and under­standing this material is important for proper use of
this unit. To access the information plate, the front
panel must be removed; see Figure 2.

FRONT PANEL

Remove front panel from unit by grasping the panel
firmly at the center top and center bottom. Pull the
panel upward at the bottom and forward at the top to
release magnetic latches and partition hooks. See
Figure 2.

NOTE: Front panel may be secured to chassi s wi th
2 screws located behind indoor air inlet filters. In order
to remove these screws, the filters must be removed
first. Refer to page 11 in this manual for instructions on
removing indoo r air in l et fi lt er s.

IMPORTANT: The front panel has to be off the unit
to complete future checks and installation proce­dures. Do not reinstall front panel at t his time.

Using Figures 1 and 3 as reference, verify that the
packaged terminal product ordered will operate prop­erly in your facility. If you do not understand the in­formation given or have questions about the product,
please call your local dealer or distributor.

US

C

FIGURE 2 — REMOVING FRONT PANEL

Replacement Package Terminal Air Conditioner,
CLASSIFIED BY UNDERWRITERS LABORATO­RIES INC., AS TO ELECTRIC
SHOCK, FIRE AND CASUALTY
HAZARDS ONLY. FOR FIELD
INSTALLATION WITH EXISTING
WALL SLEEVES, OUTDOOR LOU­VERS, AND INDOOR PANELS AS
SPECIFIED ON THE PRODUCT.

2

Series Designation

PTAC (Packaged Terminal Air Conditioner)

Comfort Series

CE – Cooling with Electric Heat
CQ – Heat Pump

Premier Series

PC – Cooling Only
PE – Cooling with Electric Heat
PQ – Heat Pump

Latest Revision

A – Z

Electric Heater Size

2 – 2.3 kW
3 – 3.4 kW
5 – 5.0 kW

Cooling Capacity (nominal)

07 – 7,000 Btuh
09 – 9,000 Btuh
12 – 12,000 Btuh
15 – 15,000 Btuh

FIGURE 3 — MODEL NUMBER NOMENCLATURE

52 PE A 3 12 3 0 1 AA

Chassis Options

AA – Standard
CP – Corrosion Protection
RC – Wall Thermostat Control (Not available
on cooling only units)
RP – Wall Thermostat Control with

Corrosion Protection (Not available on

cooling only units)

Packaging

1 – Domestic

Non-Performance

Changes 0-9

Electrical Data

3 – 230/208-v, 60 Hz
4 – 265-v, 60 Hz

To install the front panel, follow the procedure out­lined below:

Replace the unit front panel.

1. Hold the front panel firmly at the center top and
center bottom at a 5 to 10 degree angle from
vertical.

2. Place the top of the front panel onto the unit mak­ing sure the top engagement posts have engaged
the slots on the unit. Front panel should be flat
against the top of the unit.

3. Gently lower the front panel onto the cha ssis,
ensuring that the power cord (or conduit) is routed
through the front panel notch. Magnetic la tches at
bottom of front p anel will secure th e front panel to
the unit.

To install locking feature on front panel, be sure front
panel is already installed on unit and follow the steps
below:

NOTE: Two field-supplied no. 8,

1

/2-in. sheet metal

screws are required to secure front panel to chassis.

1. Remove both indoor a ir inlet fi lters to expose fro nt
panel engagement holes. See Figure 4.

2. Secure front panel to chassis by attaching the
field-supplied screws into engagement holes. Do

not over tighten.

3. Replace both indoor air inlet filters.

NOTE: Front panel alignment may have to be
adjusted slightly to line with chassis.

TOP PARTITION

DISCHARGE
DECK

ENGAGEMENT
HOLE

FRONT PANEL
SLOT

FIGURE 4 — FRONT PANEL INSTALLATION

WITH LOCKING FEATURE

3

ELECTRICAL DATA

ELECTRICAL SHOCK HAZARD

DO NOT alter cord or plug, and DO NOT use an
extension cord. Personal injury or damage to the
unit may result.

Be sure that your outlet matches the appropriate
blade configuration of the supplied plug and that it is
within reach of the service cord. A hardwire kit is
available as an accessory to change cord-connected
units to hardwired units. (See Accessories table on
page 15.)

IMPORTANT: All standard cord-connected 265-v
units will require a field-installed electrical sub­base accessory.

ALL UNITS

■ WIRE SIZE — Use recommended wire size given in

Table 1 and install a single branch circuit. All wiring
must comply with local and national codes. All units

are designed to operate off single branch cir­cuits only.

NOTE: Use copper conductors only.

■ GROUNDING — For safety and protection, the

unit is grounded through the service cord plug or
through separate ground wire provided on hardwired
units. Be sure that the branch circuit or general pur­pose outlet is grounded.

TABLE 1 — SUGGESTED BRANCH CIRCUIT

WIRE SIZES*

NAMEPLATE AMPS AWG WIRE SIZE†

7.0 to 12 14

12.1 to 16 12

16.1 to 24 10

LEGEND
AWG — American Wire Gage
*Single circuit from main box.

†Based on copper wire at 60 C temperature rating.

VOLTAGE SUPPLY

Check voltage supply at outlet. For satisfactory
results, the voltage range must always be within the
ranges found on the data information plate
(shown in Figure 1).

■ CORD-CONNECTED UNITS — The 250-v field-

supplied outlet must match the plug for the standard
208/230-v units and be within reach of the service
cord. The standard cord-connected 265-v units require
an accessory electrical subbase for operation. See
Accessories table, page 15, for subbase selection. Refer
to Table 2 for proper receptacle and fuse type.

■ POWER CORD PROTECTION — The power cord

for the 230/208-v unit provides both personal shock
protection and power cord fire prevention. Unit power
automatically disconnects when unsafe conditions are
detected. Power to the unit can be restored by pressing
the RESET button on plug head.

Upon completion of unit installation for 230/208-v
models, an operational check should be performed
using the TEST/RESET buttons on the plug head. See
Figure 5.

NOTE: The 265-v models do not incorporate this
feature as they require use of the electrical subbase
accessory.

TABLE 2 — RECEPTACLES AND FUSE TYPES — 250,265 VOLT S

RECEPTACLE

15 Amps 20 Amps 30 Amps 15 Amps 20 Amps 30 Amps

RATED VOLTS 250 250 250 265 265 265
TIME-DELAY TYPE

FUSE (or HACR Circuit Breaker)

LEGEND
HACR — Heating, Air Conditioning, Refrigeration
*May be used for 15-amp applications if fused for 15 amp.

15 20* 30 15 20 30

4

INSTALLATION

CHASSIS INSTALLATION

Units are shipped without a sleeve. In applications
where unit is a replacement, it is recommended that a
Carrier sleeve and grille be used.

The 52C and 52P units can retrofit General Electric,
Amana, Trane, and Friedrich sleeves/grilles (be sure
outdoor grille is installed on the sleeve). See Table 3
for details. Carrier Corporation must approve any
other retrofit application.

For competitive retrofit applications, be sure that the
foam seals (factory-installed on the tube sheets) pro­vide a good seal between the outdoor grille and out­door coil tube sheets. These foam seals provide a
barrier to separate outdoor coil leaving air from mix­ing with the outdoor incoming air (known as air recir­culation).
See Figure 5.

For retrofit applications, foam seals on outdoor coil
tube sheets must make a seal between the coil and
the grille or loss of performance and premature
damage to the major components can result.

TABLE 3 — RETROFIT WALL SLEEVES

MANUFACTURER WALL SLEEVE PART NUMBER

General Electric Metal Sleeve RAB71

Amana Metal Sleeve WS900B
Trane Metal Sleeve SLV149
Friedrich T-Series Metal 11

*FR-SLEEVE-EXT accessory is required for retrofit into Friedrich

(T-Series) wall sleeves.

Plastic Sleeve RAB77

1

/2-in. deep wall sleeve*

Standard depth wall sleeve 16 x 42 x 13
PXWS

3

/4-in.

INDOOR-AIR
INLET
FILTERS

FRONT
PANEL

DISCHARGE
GRILLE

WIRE SCREEN

OUTDOOR
ORIFICE

T

E

1

S

.P

R

T

E

S

2

S

IN

.P

R

L

E

U

S

G

G

E

T

IN

R

B

T

E

U

O

C

T

P

E

T

3

P

O

O

.P

T

W

N

A

R

.

E

C

E

R

L

S

E

S

S

.

T

H

E

O

S
T

U

4

B

L

.

D

U

P

L

R

T

IG

T

E

O

S

H

N

S

T.

U

R

F

O

N

E

R

S

IT

D

U

E

O

T

S

B

N

E
.

O

U

T

T

T

U

O

S

N

E

A

I
S

G

A

T

IN

E
S

T

A
B

O
V
E

F
A

I
L
S

INDOOR

PLUG TEST/

COIL

RESET BUTTONS

FIGURE 5 — UNIT COMPONENTS

COIL TUBE
SHEETS

BASEPAN

OUTDOOR
GRILLE

WALL
SLEEVE

5

■ COMP ETITIVE SLEEVE PREPARATION

IMPORTANT: Inspect the wall sleeve thoroughly
prior to installation. Manufacturer does not assume
responsibility for costs or damages due to defects in
the sleeve or improper installation.

Disconnect all power to unit to avoid possible electri­cal shock during installation.

Remove any existing foam baffles that are installed on
the outdoor grille if present. See Figure 6.

GE Sleeves Only
Metal Wall Sleeve — Remove metal clip on mounting

rail located on left, inside bottom of metal sleeve and
discard. See Figure 7.

Plastic Slee ve — Remove bottom seal from plastic
sleeve. See Figu re 8.

■ INSTALLATION OF A CARRIER WALL SLEEVE

USING A NON-CARRIER GRILLE

This application has become more common due to
pre-manufactured windows with built-in grilles or ren­ovations where a Carrier sleeve is used with an exist­ing non-Carrier grille.

Use of a Carrier wall sleeve with a non-Carrier grille
requires installation of an Accessory Baffle Kit, which
ensures a good seal between the unit and exterior
grille and prevents air recirculation. (See Figures 9
and 10.) Air recirculation is a large contributor to
performance loss and premature damage t o major
components.

FIGURE 7 — REMOVE METAL CLIP ON

GE METAL SLEEVE

FIGURE 8 — REMOVE BOTTOM SEAL FROM

GE PLASTIC SLEEVE

BAFFLES

FIGURE 6 — REMOVE EXISTING BAFFLES ON

COMPETITIVE OUTDOOR GRILLES

FIGURE 9 — ACCESSORY BAFFLE KIT

FIGURE 10 — INSTALLATION COMPLETE

6

■ INSTALL CHASSIS IN SLEEVE (See Figures 11 to

13)

1. Inspect foam gaskets (top, bottom, both sides) on
chassis. Replace foam gaskets if torn or missing.

IMPORTANT: The gaskets combine with the sleeve
face to create a weather barrier. If the chassis is
installed in a non-Carrier sleeve, this weather bar­rier may not be effective.

Chassis weighs up to 150 lb. For personal protection,
seek help when lifting the unit. Lift unit by holding
unit basepan.

SIDE
GASKET

TOP
GASKET

FACTORY-INSTALLED
FOAM SEALS

2. If retrofitting into a GE, Amana, Trane, or
Friedrich wall sleeve/grill e, remove any existing
foam seals from competitive manufacturer’s grille
before installing unit.

3. Remove shipping tape from vent door. See Figure 1 1.

Failure to remove shipping tape will prevent fresh
air vent door from opening and may result in damage
to the vent door cable.

4. Carefully remove power cord packing material
and discard.

5. Lift chassis level with wall sleeve.

6. Slide chassis into wall sleeve until foam gaskets
rest firmly against front of wall sleeve. See
Figure 12.

7. Screw chassis to wall sleeve with four 1

3

/4-in. long
screws taped to the control box. Screw holes are
located on both sides of the mo unting angles of th e
chassis. For Carrier wall sleeves, use the top-most
and bottom-most screw holes. For competitive
wall sleeves, line up the correct attachment holes
on the chassis with the holes in the sleeves. See
Figure 13.

BOTTOM
GASKET

FIGURE 12 — UNIT GASKETS

AND TUBE SHEETS

TOP SCREW HOLE
(CARRIER SLEEVE)

COMPETITIVE
MANUFACTURER
SLEEVE
ATTACHMENT
HOLES

BOTTOM SCREW
HOLE
(CARRIER SLEEVE)

COIL TUBE
SHEETS

VENT
DOOR

SHIPPING
TAPE

VENT DOOR
CABLE

FIGURE 11 — LOCATION OF SHIPPING TAPE

ON VENT DOOR

FIGURE 13 — CHASSIS MOUNTING

7

WALL THERMOSTAT INSTALLATION

The following instructions apply to RC and RP units
only.

NOTE: Carrier thermostats are recommended. See
Accessories section.

IMPORTANT: Only trained, qualified personnel
and service mechanics should install electrical
accessories on Carrier 52C and 52P series products
per Carrier’s installation instructions. Please con­tact your local electrical contractor, dealer, or dis­tributor for assistance.

■ THERMOSTAT WIRE ROUTING — Thermos ta t

wire is field supplied. Recommend ed wire gage is 18 t o
20 gage solid thermo stat wire. The rmostat wire should
always be routed around or under, NEVER through,
the wall sleeve. The wire shoul d then be rout ed behind
the front panel to the easily accessible terminal con­nector. See Figures 14 and 15.

■ INSTALL THERMOSTAT — All remote control

units.

1. Check to be sure power to unit is disconnected.

2. Pull terminal connector to remove.

NOTE: Terminal connector can be removed and re­placed to simplify thermostat wiring.

3. Connect wires from terminals on the thermostat
to terminals on chassis terminal board connector.
See Figures 15 and 16.

4. Reinstall terminal connector.

5. Restore power to unit.

NOTE: Refer to thermostat installation instructions
for details on installing thermostat.

NOTE: Fan speed is user-selectable from the control
panel on the unit.

R

Y

W

G

O

C

HI

R

Y

W

G

O

C

FAN SPEED
SELECTOR
SWITCH

TERMINAL
CONNECTOR

THERMOSTAT
WIRE (FIELD
SUPPLIED)

THERMOSTAT

POWER
CORD

LO

FAN SPEED

FIGURE 14 — CONTROL BOX TERMINAL

CONNECTOR FOR WALL THERMOSTAT MODELS

FIGURE 15 — TERMINAL CONNECTOR

REMOVAL AND REPLACEMENT

R

G

TYPICAL

WALL

THERMOSTAT

Y

W

O

C

TERMINAL

BLOCK

SEE
NOTE #1

SEE
NOTE #2

NOTES:

1. Use terminal “O” for heat pump connection only.

2. Terminal C (common) is typically only required for digital thermostats.

3. See table below for terminal descriptions.

TERMINAL DESIGNATION

R 24 VAC
G Fan

Y Compressor
W Electric Heat
O Reversing Valve

C Common

FIGURE 16 — WIRING CONNE CTIONS

8

OPERATION

IMPORTANT: When unit is first started, high
humidity conditions can cause co ndensation to form
on discharge grille. Keep doors and windows closed.
Room humidity decreases and moisture evaporates.

COMFORT CONTROLS

■ ADJUST AIRFLOW DIRECTION — The discha rge

air grille is mounted on the front panel so that the air
discharges forward. If upward discharge is required,
remove the grille by removing screws on back of front
panel. Rotate grille 180 degrees and reinstall on the
front panel.

■ ADJUST VENT — The vent handle is on the left

side of the unit. Turn handle to open or close vent.
Vent will remain in last desired position until handle
is turned again. Magnet will ensure positive closure.
See Figure 17.

■ SETTING TEMPERATURE LIMITS — Setting tem-

perature limits on the unit provides the user a
restricted range of temperature control. See Figure 18.

NOTE: This adjustment is option al and is not applica­ble to remote control units.

The temperature limits are factory set to full range,
which is 60 F to 90 F. To set restricted rotation of the
temperature control knob:

1. Remove front panel.

2. Remove temperature control knob to expose tem­perature limiter.

3. Remove standoff pins from the 60 F and 90 F indi­cator holes.

4. Replace standoff pin in hole for desired minimum
temperature.

5. Replace standoff pin in hole for desired maximum
temperature.

6. Reinstall temperature control knob.

7. Reinstall front panel.

NOTE: Temperature indicators stamped on tempera­ture limiter are approximate and represent degrees F.

75

70

65

60

90

TEMPERATURE
CONTROL
STANDOFF
PINS

FAN CYCLE
SWITCH

80

85

CON

CYC

MAGNET

VENT
DOOR

VENT
FILTER

FIGURE 17 — VENT DOOR

VENT HANDLE

E

S

O

L

C

N

PE

O

SET
SCREW

OUTDOOR
THERMOSTAT
(HEAT PUMP
UNITS ONLY)

S

L

I

A
F

E

V

O
B

A
T

S

E

T

S

I

E

S

U

T

O

N

O

D

.

E

S

U

R

O

F

N

I

A

G

A

N

O

T

T

U

B

T

E

S

E

R

S

S

E

R

P

.

4

.

T

H

G

I

L
D

L

U

O

H

S

T

I

N

U

N

O

T

T

U

B

T

S

E

T

S

S

E

R

P

.

3

.

E

L

C

A

T

P

E

C

E

R

R

E

W

O

P

O

T

N

I

G

U

L

P

.

2

.

N

O

T

T

U

B

T

E

S

E

R

S

S

E

R

P

.

1

T

E

S

T

IN

G

FIGURE 18 — OPERATING CONTROLS

9

OPERATING CONTROLS

The following controls are located on the front of the
control box door, under front panel. To obtain access to
operating controls, remove the unit front panel as
shown on page 2. See Figure 18.

■ FAN CYCLE SWITCH — (Typically available at

wall thermostat on RC or RP units.) This allows the
fan to operate in two modes:

CON (Continuous)
run continuously, circulating air even when the tem­perature setting has been satisfied. This switch helps
to maintain the room temperature closer to the ther­mostat setting. Use this switch po sition when maxi­mum comfort is desired. This is the factory default
setting.

CYC (Cycle)
and off with the compressor during heating or cooling.
The fan stops when the temperature setting is satis­fied. This results in longer unit off-time and wider
variations in room temperature and humidity.

■ OUTDOOR THERMOSTAT (52CQ and 52PQ HEAT

PUMP UNITS ONLY) — If the setscrew is left at the
factory setting (in the heat pump position), the unit
will operate in the reverse cycle heating mode. See
Figure 18. When the temperature of the outdoor coil
reaches 20 F (approximately 35 F outdoor air tempera­ture), the compressor will shut down as unit is no
longer capable of adequate heating in heat pump
mode. The electric heater then becomes the primary
heating source. The electric heater remains on until
the temperature of the outdoor coil reaches 40 F; then
the electric heater is shut off and the compressor is
energized. Once the compressor is energized, the heat
pump again becomes the primary heating source.

To set unit to operate in electric heat mode only, turn
the setscrew to the electric heat positi on. See Fi gure 18 .

— This setting allows the fan to

— This setting allows the fan to cycle on

IMPORTANT: If setscrew on standard heat pump
unit is set to electric heat mode operation, the com­pressor is disabled for both heating and cooling
operations. If setscrew on heat pump unit with wall
thermostat control is set to electric heat mode
operation, the compressor will be disabled only for
heating operation.

OPERATING MODES (See Figures 19

and 20.)

■ OUTSIDE AIR — To bring outside air into occupied

space, turn the vent handle to the full open position.
See Figure 17.

■ OFF — The OFF mode terminates unit operation.

■ FAN— The FAN mo de will circulate air in the space

at high speed and at high or low speed for cool ing onl y
models.

■ HIGH HEAT OR HIGH COOL — Select mode and

rotate temper atu r e kn ob to d esi re d c omfo r t le v el. T hi s
function provides maximum heating or cooling, and is
recommended to raise or lower the room temperature
quickly.

■ LOW HEAT OR LOW COOL — Select mode and

rotate temper atu r e kn ob to d esi re d c omfo r t le v el. T hi s
function provides minimum heating or cooling with
maximum dehumidification and quietest operation.

■ FAN SPEED CONTROL FOR 52P AND 52C WALL

THERMOSTAT MODELS — For maximum comfort,
fan speed is user selectable at the unit. See Figure 20.

FIGURE 19 — 52P UNIT CONTROLS SHOWN

WALL THERMOSTAT CONTROL SHOWN

FIGURE 20 — 52P UNIT WITH

(Blank Plate)

10

CARE AND MAINTENANCE

In order to maintain proper performance of your pack­aged terminal air conditioner or heat pump, it is very
important that the fan and outdoor coil, the blower
wheel, blower scroll, electric heater, and all drain pas­sages are thoroughly cleaned at least once per year.
Carrier recommends that as a minimum, the cleaning
should be conducted prior to the start of each heating
season. The air inlet filters should be cleaned every
month.

Depending on local condition s, more freq uent cleaning
of the unit may be required to ensure optimum perfor­mance and long operating life. Examples of these spe­cial conditions include areas where construction dust
or heavy airborne dirt is found, or environments that
promote the growth of fungus.

Some local conditions and environments can cause
fungi to grow inside the air conditioner, especially on
indoor blower section. Dried fungi, dirt and other
foreign material are fire hazards. Be sure to clean
unit according to the instructions that follow.

INDOOR-AIR INLET FILTERS

■ INDOOR-AIR INLET FILTERS should be cleaned

once each month.

FIGURE 21 — INDOOR-AIR INLET

FIL TER REMOVAL

IMPORTANT: Filters may become clogged if not
cleaned properly. Clogged filters will restrict air­flow which may lead to severe component damage
and efficiency loss.

■ CLEANING INDOOR-AIR INLET FILTER — Two

interchangeable air filters are located on the backside
of the front panel. Each can be removed and cleaned
one at a time. To remove and clean the filter, follow the
steps below:

1. Grasp filter with both hands.

2. Gently pull the filter up and away from the unit.
See Figures 5 and 21.

3. To clean filter, use a vacuum or soft bristle brush
with a small amount of mild deterg ent.

NOTE: If detergent is used, remove any detergent
residue with a gentle stream of clean water.

4. Allow filters to air dry.

5. Re-insert dry filters back into front panel.

Additional filters are available in multi-packs. Refer to
Accessories section.

11