37
• Sample Before Start -
The SBS routine is used in the
cooling mode. This routine runs the unit fan on low speed
for up to 120 seconds. The sample fan is aborted if com-
pressor demand is detected. To avoid unnecessary sam-
pling the period between samples will be based on specific
room conditions. The default sample before start period
after a power up is 5 minutes. The period is corrected ev-
ery time a sample run is completed without a compressor
demand. The minimum sample period is 5 minutes and
the maximum period is 15 minutes.
• Remote Temperature Sensor -
An auxiliary tempera-
ture sensor ( RTS02) may be connected to the control that
senses actual room temperature. This sensor replaces the
Indoor Ambient Thermistor and will connect to the Indoor
Air terminals on the control.
• Front Desk Control -
The front desk control terminals are
FD1 and FD2. These terminals will provide a connection
for a user supplied switch that will allow the operation of
the unit to be remotely defeated.
• Transfer Fan-
A transfer fan may be used if a user sup-
plied relay is connected to TF1 and TF2. Make sure the
relay is a manufactured approved relay. The relay will be
energized whenever the blower/fan relay is energized.
• Emergency Hydronic Heat -
A switch can be added to
the EH & IN terminals to close the circuit to enable the fan,
enable the heater relay and lockout the compressor to
continue minimum operations with auxiliary power, if the
main power goes out.
• On Board Diagnostics -
The LED light will flash once ev-
ery 6 seconds. If an error occurs the LED will flash from 2
to 8 flashes every 6 seconds. Refer to the chart below for
possible causes for the flash codes. See page 37 for diag-
nostics on the digital board.
FLASHES
SITUATION
CORRECTIVE
ACTION
1 Flashes
Control OK
Board OK
2 Flashes
24vac Fuse Blown
Replace Fuse
3 Flashes
Indoor Coil Thermister Failure
Replace Indoor Coil
Thermister
4 Flashes
Mode Switch Failure
Replace Board
5 Flashes
Thermostat Control
Replace Board
6 Flashes
Thermostat Input Failure
Replace Thermostat or
Correct Wiring
8 Flashes
Indoor Ambient
Thermister Failure
Replace Thermister
• Temperature Limiter Switch-
A three position dip switch
will modify the temperature desired setting by activating
the appropriate switch. Only one switch may be activated
at a time.
SWITCHES
"A" On
70
78
65
73
"B" On
68
81
68
76
"C" On
66
81
61
78
"D" All Off (Default)
63
88
58
83
COOLING RANGE HEATING RANGE
• Self diagnostic Mode-
The diagnostic mode is initiated
by the following routine. Set the thermostat in the coolest
position and the mode switch in the off position. Rotate
the thermostat counterclockwise to the warmest setting
and rotate the mode switch counterclockwise to the fan
only position simultaneously and wait two seconds (or until
fan relay engages). Return the thermostat and mode switch
to their starting positions by rotating them both clockwise
simultaneously. The diagnostic routine will run the unit
through each mode in the following sequence:
MODE
TIME
Fan Only
5
Off
1
High Cool
17
Off
3
(reversing valve energize)
High Heat
(rev cycle)
17
Off
1
Low Heat
(elec heat)
5
DIGITAL BOARD DIAGNOSTICS
If a failure is detected on the digital board, there will be a green
light constantly lit up. This light is located under the OFF touch
pad button. The board will need to be programed into the Diag-
nostic Maintenance & Status Report mode to determine the
failure and the procedures to correct the failure.
DIAGNOSTIC MAINTENANCE & STATUS REPORT
To enter
Diagnostic Status Report mode,
press and hold
the up and down
arrows and, while holding, quickly
press the COOL key
twice.
Active Failures.
•
If there are no active failures or lockouts, the display will
show a double dash, “- -”. If there is a code listed, see the
unit “Diagnostic Codes” chart for a list of definitions.
Operating Temperatures.
•
If not in Diagnostic Status Report Mode, enter as instructed
above and press the Fan Speed
key.
OPERATIONS
