Isc Board - Sequence Of Operation - Carrier WeatherExpert Puron 50LC 08 Series Installation Instructions Manual

ERROR #
Check Smoke Detector/PMR/AUX
1
Check HPS/LPS/COFS
2
Call for Y3 with no call for Y1. Check Y1 wiring.
3
Call for Y3 with no call for Y1/Y2. Check Y1 wiring.
4
Call for Y2 with no call for Y1. Check Y1 wiring.
5
Call for W2 with no call for W1. Check W1 wiring.
6
Call for heat (W1/W2) and cooling (Y1/Y2/Y3). Check thermostat wiring.
7
Call for heat (W1/W2) with no G. Check G wiring.
8
Call for cooling (Y1/Y2/Y3) with no G. Check G wiring
9
Call for heat (W1/W2) and cooling (Y1/Y2/Y3) with no G.
10
Check thermostat and G wiring.
Check ISC Board and the thermostat wiring
11
Check ISC Board and the thermostat wiring
12
Check ISC Board and the thermostat wiring
13
Check ISC Board and the thermostat wiring
14
Check ISC Board and the thermostat wiring
15
NOTES:
1. Green LED Blinking at 1Hz indicates normal operation.
2. Solid red LED indicates an error exists, see above LED configuration.
ISC BOARD – SEQUENCE OF OPERATION
General
The Carrier Integrated Staging Control (ISC) is intended for use
with a standard thermostat or direct digital controls (DDC) capa-
ble of three cooling stages. After initial power to the board, a
Green LED will blink with a 1 second duty cycle indicating the
unit is running properly. In the event of the ISC board failing, the
Green LED will be OFF or continuously ON. When the unit is not
running properly, the Green LED will blink along with Red LED
lights. The Red LED light configuration will indicate the type of
error the board has identified. See Fig. 52 for LED locations and
Table 4 for a list of status codes.
The ISC board can be remotely shutdown by removing Jumper 4
and wiring to the Remote Shutdown terminal. The Smoke Control
Module can shut down the unit by removing Jumper 3 and wiring
to the Smoke Shutdown terminal. The Smoke Alarm terminal on
the ISC Board provides a pass through connection should a smoke
alarm signal be connected. In the case of the RTU Open option,
the RTU Open controller provides the signal which is passed
through the ISC board to the Smoke Alarm terminal.
The crankcase heater will run at all times except when the com-
pressors are running. An auxiliary power supply (24 vac) available
at TB-4 Terminal is provided to power auxiliary equipment. An
optional Phase Monitor Relay can be wired to the PMR terminal
by removing Jumper 5. An optional Condensate Flow Switch can
be wired to the COFS Terminal by removing Jumper 7.
Ventilation
In the Ventilation/Fan Mode (G on the thermostat), the indoor fan
will run at low speed and the damper will operate at minimum po-
sition.
Cooling
In the Cooling Mode, the small and large compressors will be se-
quenced to maintain the thermostat temperature setpoint. The ta-
ble below shows the cooling operation based on the following
conditions.
The outdoor fan and VFD controlled indoor fan will operate at
low, medium and high speed. The RPM is factory set by the CFM
and static pressure requirements for the unit installed.
Table 4 — Status Code Descriptions for ISC Board LEDs
ERROR NAME
LED01
RED
RED
RED
RED
RED
RED
RED
RED
INPUT
Compressor
Thermostat
C1
First Stage
On
Cooling (Y1)
Second Stage
Off
Cooling (Y2)
Third Stage
On
Cooling (Y3)
Humidi-MiZer System (Optional)
®
In the Dehumidification Mode, both compressors will run and In-
door airflow will be rise to High Speed.
At subcooler reheating mode (reheat-1), during part load condi-
tions when the room temperature and humidity are above the set
point, the unit initiates the sub-cooling mode of operation; a call
for cooling and dehumidification. RDV (Reheat Discharge Valve)
and TWV (Three Way Valve) close; Indoor and Outdoor airflow
will rise until reaching 100% of Speed.
At hot-gas-bypass reheating mode (reheat-2), when there is a call
for dehumidification without a call for cooling, a portion of the hot
gas from the compressor bypasses the condenser coil when RDV
opens and hot gas is fed into the liquid line, TWV closes in this
mode and the system provides mainly latent cooling. Indoor air-
flow will rise until reaching 100% of Speed, Outdoor airflow will
run at High speed as long as outdoor temperature is above 80°F
(26.7°C); when operating in this mode below 80°F (26.7°C) OAT,
the system outdoor fan will operate as shown in the table below
based on size.
LC SIZE RPM
08 160
09
160
12
160
Economizer (Optional)
When the economizer is in Free Cooling Mode and a demand for
cooling exists (Y1 on the thermostat), the economizer will modu-
late the outdoor-air damper to provide a 50°F (10°C) to 55°F
(13°C) mixed-air temperature into the zone and run the indoor fan
at high speed. As mixed-air temperature fluctuates above 55°F
(13°C) or below 50°F (10°C) dampers will be modulated (open or
close) to bring the mixed-air temperature back within control.
Upon more call for cooling (Y2 on the thermostat), the outdoor-air
damper will maintain its current position, compressor C1 will run
and the outdoor fan will run at low speed. If there is further
33
LED INDICATION
LED02 LED03 LED04 LED05
RED
RED
RED
RED RED
RED RED
RED
RED RED RED
Blinking
RED Green RED RED
LED
RED RED
(Note 1)
RED RED
RED RED
RED
RED
RED RED
OUTPUT
Indoor Outdoor
Compressor
Fan Fan
C2
Speed Speed
Low
Off Low
(700 rpm)
Medium
On Medium
(800 rpm)
High
On High
(1000 rpm)
NUMBER OF NUMBER OF
FANS ON FANS OFF
2 1
2 1
2 1