Bryant PREFERRED 538A Installation Instructions Manual

538A
PREFERREDT SERIES AIR CONDITIONER
WITH PURONR REFRIGERANT
1--1/2 TO 5 NOMINAL TONS

Installation Instructions

literature and attached to the unit. Consult local building codes and
the current editions of the National Electrical Code (NEC)
NFPA70.

In Canada, refer to the current editions of the Canadian Electrical
Code CSA C22.1.

Recognize safety information. This is the safety--alert symbol
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury. Understand
the signal words DANGER, WARNING,andCAUTION. These
words are used with the safety--alert symbol. DANGER identifies
the most serious hazards which will result in severe personal injury
or death. WARNING signifies hazards which could result in
personal injury or death. CAUTION is used to identify unsafe
practices which may result in minor personal injury or product and
property damage. NOTE is used to highlight suggestions which
will result in enhanced installation, reliability, or operation.

.

Fig. 1 --- 538A

NOTE: Read the entire instruction manual before starting the

installation.

TABLE OF CONTENTS

PAGE

SAFETY CONSIDERATIONS 1........................

INSTALLATION 2--3................................

Step 1 -- Complete Pre--Installation Checks 2............

Step 2 -- Rig and Mount Unit 2......................

Step 3 -- Complete Refrigerant Piping Connections 2.....

Step 4 -- Make Electrical Connections 3................

START--UP 4........................................

SERVICE 4.........................................

MAINTENANCE 6...................................

TROUBLESHOOTING 6..............................

SAFETY CONSIDERAT IONS

Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory--authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.

Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions included in

!

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or
death.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position. There
may be more than 1 disconnect switch. Lock out and tag
switch with a suitable warning label.

!

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental
pollution.

Remove and recycle all components or materials (i.e. oil,
refrigerant, etc.) before unit final disposal.

WARNING

CAUTION

INSTALLATION

!

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this warning could result in personal injury
or equipment damage.

Puron (R--410A) refrigerant systems operate at higher
pressures than standard R--22 systems. Do not use R--22
service equipment or components on Puron refrigerant
equipment.

WARNING

!

PERSONAL INJURY AND EQUIPMENT DAMAGE
HAZARD

Failure to follow this caution may result in personal injury
and / or equipment damage.

DO NOT operate the unit without a filter or with grille
removed.

CAUTION

Rigging

!

PERSONAL INJURY AND/OR EQUIPMENT DAMAGE
HAZARD

Failure to follow this caution may result in personal injury
and/or equipment damage.

Be sure unit panels are securely in place prior to rigging.

CAUTION

Step 1 —Complete Pre-- Installation Checks

Unpack

Move the unit to final location. Remove unit from carton, being
careful not to damage service valves and grilles.

Inspect

File a claim with the shipping company if shipment is damaged or
incomplete. Check the unit nameplates to ensure units match job
requirements.

Consider System Requir

Consult local building codes and NEC for special installation

538A

requirements.
Allow sufficient space for airflow clearance, wiring, refrigerant

piping, and servicing unit. Locate unit so that condenser airflow is
unrestricted on both sides.

Unit may be mounted on a level pad directly on base legs or
mounted on raised pads at support points.

Matching the Condensing Unit to an Indoor

The 538A018--060 condensing units can be matched to
corresponding indoor units. The 538A unit can be matched with
under--ceiling duct--free and residential ducted fan coils and
evaporator coils. Refer to separate indoor unit literature for more
information.

Step 2 —RIG AND MOUNT UNIT

Mounting on Gr

Mount unit on a solid, level concrete pad. Position unit so water or
ice from roof does not fall directly onto unit. Accessory stacking
kits can be used when units are to be stacked. See installation
instructions provided with the accessory kit. Use field--provided
snow stand or ice rack where prolonged subfreezing temperatures
or heavy snow occurs.

If conditions or local codes require unit be fastened to a pad, 6
field--supplied tie--down bolts should be used and fastened through
slots provided in unit mounting feet.

Mounting on

Mount unit on a level platform or frame at least 6 in. (152.4 mm)
above roof surface. Isolate unit and tubing from structure.

Clearance Requir

With coil facing wall: Allow 6” (152.4 mm) minimum clearance
on coil side and coil end and 36” (914.4 mm) minimum clearance
on compressor end and fan side

With fan facing wall: Allow 8” (203.2 mm) minimum clearance on
fan side and coil end and 36” (914.4 mm) minimum clearance on
compressor end and coil side.

With multi--unit application: Arrange units so discharge of one
does not enter inlet of another.

IMPORTANT: When installing multiple units, ensure the
discharge air from one unit is not drawn into another unit. When
installing single or multiple units in an alcove, roof well or partially
enclosed area, ensure there is adequate ventilation to prevent
recirculation of discharge air.

Operating

Minimum outdoor operating ambient in cooling mode without
accessory is 55_F(13_C), maximum 125_F(52_C).

Unit

Shipment

ements

Unit

ound

Roof

ements

Ambient

Keep the unit upright and lift unit using a sling. Use cardboard or
padding under the sling, and spreader bars to prevent sling damage
to the unit. See Fig. 2. Install the unit so that the coil does not face
into prevailing winds. If this is not possible and constant winds
above 25 mph are expected, use accessory wind baffle. See
installation instructions provided with the accessory kit.

NOTE: Accessory wind baffles should be used on all units with
accessory low ambient temperature control.

Field--fabricated snow or ice stands may be used to raise unit when
operation will be required during winter months. Units may also be
wall mounted using the accessory wall mounting kit.

A07396

Fig. 2 --- Lifting Unit with Sling

Step 3 —COMPLETE REFRIGERANT PIPING CONNEC­TIONS

Outdoor units may be connected to indoor units using
field--supplied tubing of refrigerant grade and condition. See
Product Data for correct line sizes. Do not use less than 10 ft (3.1
m) of interconnecting tubing.

!

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage
or improper operation.

If any section of pipe is buried, there must be a 6 in. (152.4
mm) vertical rise to the valve connections on the outdoor unit.
If more than the recommended length is buried, refrigerant
may migrate to cooler, buried section during extended periods
of system shutdown. This causes refrigerant slugging and
could possibly damage the compressor at start--up.

When more than 80 ft (24.38 m) of interconnecting tubing and
more than 20 ft (6.10 m) of vertical lift is used, consult the
residential Long Line Application Guide for required accessories.
If either refrigerant tubing or indoor coil is exposed to the
atmosphere, the system must be evacuated following good
refrigeration practices.

Run refrigerant tubes as directly as possible, avoiding unnecessary
turns and bends. Suspend refrigerant tubes so they do not damage
insulation on vapor tube and do not transmit vibration to structure.
Also, when passing refrigerant tubes through a wall, seal the
opening so that vibration is not transmitted to structure. Leave

2

CAUTION

some slack in refrigerant tubes between structure and outdoor unit
to absorb vibration. Refer to separate indoor unit installation
instructions for additional information.

Expansion

A hard shutoff, thermostatic expansion valve (TXV) is required at
the indoor section of the system for proper operation of these
products. If the indoor section of the system is not equipped with a
hard shutoff TXV, refer to Spec Sheet for the correct TXV kit to be
installed. Follow the instructions in the kit for proper installation.

Filter

The filter drier must be replaced whenever the refrigeration system
is exposed to the atmosphere.

Refer to Fig. 3 and install filter drier as follows:

Device

Drier

1. Braze 5--in. (127 mm) liquid tube to the indoor coil.

2. Wrap filter drier with damp cloth.

3. Braze filter drier to above 5--in. (127 mm) liquid tube. Flow
arrow must point towards indoor coil.

4. Connect and braze liquid refrigerant tube to the filter drier.

Provide Safety

A fusible plug is located in unit suction line; do not cap this plug.
If local code requires additional safety devices, install as directed.

Step 4 —Make Electrical connections

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury
or death.

The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault
should occur. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing
electrical codes.

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment
damage or improper operation.

Unit failure as a result of operation on improper line voltage
or excessive phase imbalance constitutes abuse and may
cause damage to electrical components. Such operation
would void any applicable Bryant warranty.

Relief

!

!

WARNING

CAUTION

538A

A05178

Fig. 3 --- Filter Drier Components

Only use factory specified liquid--line filter driers with rated
working pressures less than 600 psig.

NOTE: Do not install a suction--line filter drier in liquid line.

Make Piping Sweat

Remove plastic caps from liquid and suction service valves. Use
refrigerant grade tubing. Service valves are closed from the factory
and are ready for brazing. After wrapping the service valve with a
wet cloth, the tubing set can be brazed to the service valve using
either silver bearing or non --silver bearing brazing material.
Consult local code requirements. Refrigerant tubing and the indoor
coil are now ready for leak testing.

NOTE: Unit is shipped with Puron (R--410A) factory charge
indicated on nameplate. Unit is factory--charged for 15 ft (4.6 m) of
line--set.

Pass nitrogen or other inert gas through piping while brazing to
prevent formation of copper oxide.

!

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment
damage or improper operation.

To prevent damage to unit or service valves observe the
following:

S Use a brazing shield.

S Wrap service valves with wet cloth or use a heat sink

material.

Connections

CAUTION

!

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury
or death.

Before performing service or maintenance, be sure indoor unit
main power switch is turned OFF and indoor blower has
stopped.

Control Circuit W

Control voltage is 24 v (40 va minimum). See Fig. 4 and unit label
diagram for field--supplied wiring details. Route control wire
through opening in unit side panel to connection in unit control
box.

Fig. 4 --- 538A Typical Control Circuit Connections

NOTE: Use No. 18 AWG color--coded, insulated (35_C

minimum) wire. If thermostat is located more than 100 ft (30.5 m).
from unit, as measured along the control voltage wires, use No. 16
AWG color--coded wire to avoid excessive voltage drop.

NOTE: All wiring must conform to NEC and local codes.

NOTE: Operating unit on improper line voltage constitutes abuse

and could affect Bryant warranty. See Product Data. Do not install
unit in a system where voltage may fluctuate above or below
permissible limits.

WARNING

iring

A07398

3

Refer to Product Data for recommended fuse sizes. When making
electrical connections, provide clearance at the unit for refrigerant
piping connections.

NOTE: The 538A units use the control transformer supplied with
the matched indoor unit.

Power W

Unit is factory wired for voltage shown on nameplate. Provide
adequate, fused disconnect switch within sight from unit, readily
accessible, but out of reach of children. Provision for locking the
switch open (off) is advisable to prevent power from being turned
on while unit is being serviced.

Disconnect switch, fuses, and field wiring must comply with the
NEC and local code requirements. Use copper wire only between
the disconnect switch and unit. Use minimum 75 C wire for the
field power connection.

Route power wires through the opening in unit side panel and
connect in the unit control box as shown on the unit label diagram.
Unit must be grounded.

Connections to Duct Free Fan Coil

The 538A units are designedfor easy match--up to 619C ductfree fan
coils. Thisunit provides 24 v power forthe outdoor unitfrom the fan

538A

coil.Connectthe Y and C terminalsof theindoor unit to the Y and C
terminals.

iring

Units

START--UP

Step 1 —Preliminary Checks

1. Check that all internal wiring connections are tight and that
all barriers, covers, and panels are in place.

2. Field electrical power source must agree with unit name­plate rating.

3. All service valves must be open.

4. Belly--band crankcase heater must be tight on compressor
crankcase for those units with belly--band heaters.

Step 2 —Evacuate and Dehydrate

Field piping and fan coil must be evacuated and dehydrated.

Step 3 —Charge System

Release charge into system by opening (backseating) liquid and
suction line service valves.

Step 4 —To Start Unit

Be sure that the field disconnect is closed. Set room thermostat
below ambient temperature. Operate unit for 15 minutes, then
check system refrigerant charge. See Refrigerant Charging section
of this document.

NOTE: When using in conjunction with 619C fan coils, refer to
start-- up instructions included with fan coil for correct start-- up
procedures.

SERVICE

!

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury
or death.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position.
There may be more than 1 disconnect switch. Lock out and
tag switch with a suitable warning label.

Outdoor

A reinforced wire mount holds the outdoor fan assembly in
position. See Fig. 5 for proper mounting position.

Fan

WARNING

538A Unit Size, in. (mm)

018,024 030,036 048,060

0.433 (11.00) 0 0

Fig. 5 --- Condenser Fan Mounting Positions

High--Pressure Relief V

The high--pressure relief valve is located in the compressor. The
relief valve opens at a pressure differential of approximately 550 to
625 ± 50 psig between suction (low side) and discharge (high side)
to allow pressure equalization.

Internal Current and Temperature Sensitive

The control resets automatically when internal compressor motor
temperature drops to a safe level (overloads may require up to 45
minutes to reset). When an internal overload is suspected of being
open, check by using an ohmmeter or continuity tester.

Pumpdown Procedur

The system may be pumped down in order to make repairs on the
low side without losing complete refrigerant charge.

!

UNIT DAMAGE HAZARD

Failure to follow this caution may result in equipment
damage or improper operation.

Never open system to atmosphere while it is under a vacuum.
Equipment damage may result.

When system must be opened for service, recover refrigerant, break
vacuum with dry nitrogen before opening system.

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

2. Frontseat the liquid/mixed phase line valve.

3. Start unit and run until suction pressure reaches 20 psig.

4. Shut unit off and frontseat suction valve.

5. De-- pressurize low side of unit and recover refrigerant fol­lowing accepted practices.

High--Pressure

The high--pressure switch, located on discharge line, protects
against high discharge pressures caused by such events as
overcharge, condenser-- fan motor failure, system restriction, etc. It
opens on pressure rise at about 650 ± 10 psig. If system pressures
go above this setting during abnormal conditions, the switch
opens.

!

PERSONAL INJURY HAZARD

Failure to follow this warning could result in personal
injury or death.

DO NOT attempt to simulate these system abnormalities -­high pressures pose a serious safety hazard.

alve

Overload

e

CAUTION

Switch

WARNING

A07401

The high--pressure switch is checked with an ohmmeter. If system
pressure is below 625 psig switch shows continuity.

4

Crankcase

The crankcase heater prevents refrigerant migration and
compressor oil dilution during shutdown when compressor is not
operating. If the crankcase heater is de--energized for more than 6
hours, both compressor service valves must be closed.

NOTE: Crankcase heaters are only factory--supplied on
538A030--060 units. Addition of an accessory crankcase heater is
required for long line and low ambient cooling applications on 018
and 024 size units. See Residental Long Line Guideline.

The crankcase heater is powered by the high--voltage power of the
unit. It is connected across the line side of the contactor and is
thermostatically controlled.

PERSONAL INJURY HAZARD

Failure to follow this warning could result in personal injury
or death.

Use extreme caution when troubleshooting this device as line
voltage is continually present.

To troubleshoot:

Service V

The service valves in the outdoor unit come from the factory
frontseated. This means the refrigerant charge is isolated from the
line--set connection ports. To prevent damage to the valve, use a
wet cloth or other accepted heat sink material on the valve before
brazing.

The service valve cannot be field repaired, therefore, only a
complete valve or valve stem seal and service port caps are
available for replacement.

Refrigerant

PERSONAL INJURY AND/OR EQUIPMENT
DAMAGE HAZARD

Failure to follow this warning could result in personal injury
and/or equipment damage.

Wear safety glasses and gloves when handling refrigerant.
Do not overcharge system -- this can cause compressor
flooding.

PERSONAL INJURY AND/OR EQUIPMENT
DAMAGE HAZARD

Failure to follow this warning could result in personal injury
and/or equipment damage.

Service valves must be fully backseated to close service
port. There is no Schrader valve at the service port, and
failure to backseat the valve could result in loss of system
charge or personal injury.

Heater

!

1. Apply voltmeter across crankcase heater leads to see if heat­er voltage is on. Do not touch heater. Carefully feel area
around crankcase heater; if warm, crankcase heater is func­tioning.

2. With power off and heater leads disconnected, check across
leads with ohmmeter. Do not look for a specific resistance
reading. Check for resistance or an open circuit, and change
heater if an open circuit is detected.

alves

Charging

!

!

WARNING

WARNING

WARNING

NOTE: Do not vent or de-- pressurize unit refrigerant to
atmosphere. Remove and recover refrigerant following accepted
practices.

All units are shipped with the refrigerant charge listed on the
nameplate.

Refer to Product Data and consider the following when working
with Puron (R--410A) refrigerant:

S Puron refrigerant cylinders are rose colored.
S Recovery cylinder service pressure rating must be 400

psig, DOT (Department of Transportation) 4BA400 or
DOT BW400.

S Puron systems should be charged with liquid refrigerant.

Use a commercial type metering device in the manifold
hose when charging into suction line with compressor op­erating.

S Manifold sets should be 700 psig high side and 180 psig

low side with 550 psig low--side retard.

S Use hoses with 700 psig service pressure rating.
S Puron refrigerant, as with other HFCs, is only compatible

with POE oils.

S Vacuum pumps will not remove moisture from oil.
S PolyolEster oilsabsorbmoisture rapidly.Do notexposeoil

to atmosphere.

S Polyol Ester oils may cause damage to certain plastics and

roofing materials.

S Wrap all filter driers and service valves with wet cloth when

brazing.

S factory approved, liquid--line filter drier is required on ev-

ery unit.

S Do not usea TXV(thermostatic expansion valve)designed

for use with R--22 refrigerant. Refer to separateindoor unit
installation instructions for more details.

S f using a suction line drier, do not leave in place for more

than 72 hours.

Check Charge

Factory charge amount and desired subcooling are shown on unit
rating plate. Charging method is shown on information plate inside
unit. To properly check or adjust charge, conditions must be
favorable for subcooling charging. Favorable conditions exist
when the outdoor temperature is between 70_F and 100_F(21_C
and 38_C), and the indoor temperature is between 70_F and 80_F
(21_C and 27_C). Follow the procedure below:

Unit is factory charged for 15 ft (4.6 m) of line--set. Adjust charge
by adding or removing 0.6 oz/ft of 3/8 liquid line above or below
15 ft (4.6 m) respectively.

For standard refrigerant line lengths (80 ft/24 m or less), allow
system to operate in cooling mode at least 15 minutes. If conditions
are favorable, check system charge by subcooling method. If any
adjustment is necessary, adjust charge slowly and allow system to
operate for 15 minutes to stabilize before declaring a properly
charged system.

If the indoor temperature is above 80_F(27_C), and the outdoor
temperature is in the favorable range, adjust system charge by
weight based on line length and allow the indoor temperature to
drop to 80_F(27_C) before attempting to check system charge by
subcooling method as described above.

If the indoor temperature is below 70_F(21_C), or the outdoor
temperature is not in the favorable range, adjust charge for line set
length above or below 15 ft (4.6 m) only. Charge level should then
be appropriate for the system to achieve rated capacity. The charge
level could then be checked at another time when the both indoor
and outdoor temperatures are in a more favorable range.

538A

5

NOTE: If line length is beyond 80 ft (24.4 m) or greater than 20 ft
(6 m) vertical separation, See Long Line Guideline for special
charging requirements.

MAINTENANCE

!

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury
or death.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position.
There may be more than 1 disconnect switch. Lock out and
tag switch with a suitable warning label.

WARNING

LUBRICATION

Compr

essor

Compressor contains factory oil charge; replace oil when lost. Use
Mobile 3MA--POE oil.

CLEANING COILS

Coil should be washed out with water or blown out with
compressor air. Note that the blow--thru design causes dirt and
debris to build up on the inside of the coils. Clean coil annually or
as required by location and outdoor air conditions. Inspect coil
monthly and clean as required. Fins are not continuous through
coil sections. Dirt and debris may pass through first section,
become trapped between the row of fins and restrict condenser
airflow. Use a flashlight to determine if dirt or debris has collected
between coil sections. Clean coil as follows:

1. Turn off unit power.

2. Using a garden hose or other suitable equipment, flush coil
from the outside to remove dirt. Be sure to flush all dirt and
debris from drain holes in base of unit. Fan motors are wa­terproof.

538A

TROUBLESHOOTING

E2009 B ryant Heating & Cooling Systems 7310 W. Morris St. Indianapolis, IN 46231 Printed in U.S.A. Edition Date: 01/ 09

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

A07402

Fig. 6 --- Troubleshooting the Cooling Cycle

Catalog No. II538AN R --- 0 2

Replaces: II 538ANR---18 --- 1

6