The low voltage connections may be connected to the screw terminals or the quick connect terminals. The screw terminals and the quick con- nect terminals are physically connected on the control board.
TABLE 3: Low Voltage Connections |
| ||
|
|
| |
Terminal | Signal | Comment | |
R | 24 VAC power (fused) |
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G | Continuous Fan operation |
| |
Y/Y2 | Second or full stage |
| |
compressor operation |
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|
| ||
Y1 | First stage compressor | Not used with outdoor units | |
operation | having one stage compressors. | ||
| |||
W2 | Second stage heat operation |
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W1 | First stage heat operation |
| |
|
| 24 VAC will be present at this | |
O | Reversing valve operation | terminal when the MODE | |
jumper is in the AC position. | |||
|
| ||
|
| This is normal. | |
|
| 24 VAC will be present at this | |
HUM | Humidity switch input | terminal when the HUM STAT | |
jumper is in the NO position. | |||
|
| ||
|
| This is normal. | |
| Connection point for | This terminal is a connection | |
X/L | point only and does not affect | ||
heat pump fault indicator | |||
| air handler control operation. | ||
|
| ||
COM | 24 VAC common |
| |
SECTION VI: REQUIRED CONTROL SET-UP
The following steps must be taken at the time of installation to insure proper system operation.
1.Consult system wiring diagram to determine proper thermostat wiring for your system.
2.If heat kit is installed, change HEAT/NO HEAT jumper from NO HEAT to HEAT position.
3.If a humidistat is installed, change HUM STAT jumper from NO to YES.
4.Set the MODE jumper to A/C (Air Conditioner) or HP (Heat Pump) position depending on the outdoor unit included with the system.
5.Set airflow and comfort setting jumper to proper positions.
FUNCTIONALITY AND OPERATION
Jumper Positions
HEAT/NO HEAT Jumper
The HEAT/NO HEAT jumper configures the control for heat kit opera- tion. The jumper must be in the HEAT position if a heat kit is installed with the air handler.
With the jumper in the NO HEAT position, the control will not energize the heat relay outputs or sense the limit switch input.
If the jumper is not present, the control will operate as if the jumper is in the HEAT position. If the jumper is not present and a heat kit is not pres- ent, the control will sense an open limit condition and the blower will run continuously.
Hum Stat Jumper
The HUM STAT jumper configures the control to monitor the humidity switch input. With the jumper in the NO position, the control will ener- gize the HUM terminal with 24 VAC continually. With the jumper in the YES position, the control will monitor the HUM input to control the HUM OUT output to control an external humidifier.
If the jumper is not present, the control will operate as if the jumper is in the YES position.
Mode Jumper
The MODE jumper configures the control to operate properly with an air conditioner (AC position) or heat pump (HP position). With the jumper in the AC position, the control will energize the O terminal with 24 VAC continually. With the jumper in the HP position, the O input signal is received from the room thermostat.
If the jumper is not present, the control will operate as if the jumper is in the HP position.
SPARE Jumper
The control includes a spare jumper that can be used if a jumper is lost. The SPARE jumper does not have any effect on the operation of the control.
Airflow and Comfort Setting Jumpers
See separate section.
Status and Fault Codes
The control includes an LED that displays status and fault codes. These codes are shown in Table 4. The control will display the fault codes until power is removed from the control or the fault condition is no longer present.
TABLE 4: Fault Codes
Fault or Status Condition | LED1 (RED) | |
Flash Code | ||
| ||
Status |
|
No power to control | OFF |
Normal operation | 2s ON/2s OFF |
Control in test mode | Rapid Flash |
Control failure | ON |
Limit Faults |
|
Limit switch currently open (not in lockout) | 1 |
Multiple limit openings with no call for heat | 2 |
Multiple limit openings during one call for heat | 3 |
Single long duration limit opening | 4 |
Multiple long duration limit openings | 5 |
Fan failure | 6 |
Wiring Related Faults |
|
Simultaneous call for heating and cooling | 7 |
Internal Control Faults |
|
Control recovered from internal event | 9 |
External Relay Outputs
The control includes two outputs to drive external relays having 24 VAC coils. The outputs have a maximum rating of 1.0 Amp pilot duty at 24 VAC.
HUM OUT
The HUM OUT output can be used to drive an external relay or solenoid (24 VAC coil) to control a humidifier. The output is energized when the HUM input is energized, the HUM STAT is in the YES position, and the control has a thermostat call for heating (heat pump or electric heat).
EAC
The EAC output can be used to drive an external relay (24 VAC coil) to control an electronic air cleaner. The output is energized whenever the blower relay on the control is energized.
Heat Output and Limit Connections
The control is connected to the heater relays and limit switch using the
The control energizes the heat relays and senses the limit switch input as shown in Table 5 when the HEAT ENABLE jumper is in the HEAT position.
10 | Johnson Controls Unitary Products |
