Carrier WEATHERMAKER 48/50AJ Operation And Service Manual page 95

Single package large rooftop units with comfortlink version 5.x controls

Table of Contents

ALARM

ALERT

NUMBER

T300

Space Temperature Below Limit

T301

Space Temperature Above Limit

T302

Supply Temperature Below Limit

T303

Supply Temperature Above Limit

T304

Return Temperature Below Limit

T305

Return Temperature Above Limit

T308

Return Air Relative Humidity Below Limit

T309

Return Air Relative Humidity Above Limit

T310

Supply Duct Static Pressure Below Limit

T311

Supply Duct Static Pressure Above Limit

T312

Building Static Pressure Below Limit

T313

Building Static Pressure Above Limit

T314

IAQ Above Limit

A404

Fire Shut Down Emergency Mode (fire-smoke)

A405

Evacuation Emergency Mode

A406

Pressurization Emergency Mode

A407

Smoke Purge Emergency Mode

T408

Dirty Air Filter

A409

Supply Fan Status Failure

T409

Supply Fan Status Failure

T414

Loss of Communication with the Belimo Actuator

T414

Belimo Actuator Direction Error

T414

Belimo Actuator Failure

T414

Belimo Actuator Jammed

T414

Belimo Actuator Range Error

R-W1 Jumper Must Be Installed to Run Heat in Service

T420

Test

T421

Thermostat Y2 Input ON without Y1 ON

T422

Thermostat W2 Input ON without W1 ON

T423

Thermostat Y and W Inputs ON

T424

Thermostat G Input OFF on a Call for Cooling

T500

Current Sensor Board Failure - A1

T501

Current Sensor Board Failure - A2

T502

Current Sensor Board Failure - B1

T503

Current Sensor Board Failure - B2

A700

Supply Air Temperature Sensor Failure

T701

Staged Gas Thermistor 1 Failure

T702

Staged Gas Thermistor 2 Failure

T703

Staged Gas Thermistor 3 Failure

A704

Staged Gas Leaving Air Temp Sum Total Failure

T705

Limit Switch Thermistor Failure

LEGEND

Axxx — Alarm

CEM — Controls Expansion module

IAQ

— Indoor Air Quality

OAT — Outdoor Air Temperature

For 48/50A2,A3,A4,A5 units:

• Compressor internal overload protector is open. Internal

overload protectors are used in the Copeland compressors in

all units except size 60 ton units with voltages of 208/230-v,

380-v, and 575-v.

• Compressor external overload protector (Kriwan module)

has activated. The Copeland compressors in size 60 ton

units with voltages of 208/230-v, 380-v, and 575-v use

external overload protector modules that are mounted in the

compressor wiring junction box. Temperature sensors

embedded in the compressor motor windings are the inputs

to the module. The module is powered with 120 vac from

the units main control box. The module output is a normally

closed contact that is wired in series with the compressor

contactor coil. In a compressor motor overload condition,

the contact opens de-energizing the compressor contactor.

• Circuit breaker trip. The compressors are protected from

short circuit by a breaker in the control box. On the 020-050

Table 114 — Alert and Alarm Codes (cont)

DESCRIPTION

Pxxx — Pre-Alert

Txxx — Alert

TXV

— Thermostatic Expansion Valve

VFD — Variable Frequency Drive

ACTION TAKEN BY CONTROL

Stop cooling, but continue

to heat

Stop heating, but continue

to cool

Continue to run unit

Alert

Continue to run unit

Unit Shutdown

Run power exhaust

Run supply fan

Run supply and exhaust fans

Continue to run unit

Stop unit

Continue to run unit

Close economizer

Attempt to close economizer

Close economizer

No heat

Assume Y2 is Y1

Assume W2 is W1

Alert

Turn fan on

Stop compressor A1

Stop compressor A2

Stop compressor B1

Stop compressor B2

Stop staged gas heat

size units there is one breaker per two compressors and on

the 060 size units there is one breaker per compressor.

• Wiring Error. A wiring error might not allow the compres-

sor to start.

To check out alerts 051, 052, 055 and 056:

1. Turn on the compressor in question using Service Test

mode. If the compressor does not start, then most likely

the problem is one of the following: HPS open, open

internal protection, circuit breaker trip, incorrect safety

wiring, or incorrect compressor wiring.

2. If the compressor does start verify it is rotating in the

correct direction.

IMPORTANT: Prolonged operation in the wrong direction

can damage the compressor. Correct rotation can be veri-

fied by a gage set and looking for a differential pressure

rise on start-up.

RESET

PROBABLE CAUSE

METHOD

Automatic

Outdoor dampers stuck, no load

Automatic

High load, dampers open