Controller Alarms; Rotation Sensor; Digital Scroll - Greenheck ERCH-20 Installation, Operation And Maintenance Manual

Troubleshooting - Controller Alarms
The first step in troubleshooting the unit is to check
the on-board alarm indicators. Several of the electronic
controls in the unit monitor the system for faults and will
go into alarm, shutting down the unit or a single function
within the unit.
Microprocessor Controller
Check the screen on the
microprocessor for an alarm
condition. If it is in alarm condition,
a message will show on the
screen.
The microprocessor controller is located in the main
control center. If it is in alarm condition, the alarm button
will blink red. Press the alarm button to see the specific
condition or to reset the microprocessor. Refer to the
Installation Operations and Maintenance manual for
detailed information on fault codes and see the unit-
specific wiring diagram.
Phase Monitor
The phase monitor has two LED
indicator lights, one red and one
green. Green indicates proper
operational status, red indicates the
unit has detected a fault and is in
alarm condition.
Variable Frequency Drive (VFD)
VFDs have a display screen that will
show an alarm condition. If a fault such
as a voltage spike occurs, the VFD will
go into alarm and will not reset until a
hard restart is performed. See the unit-
specific manufacturer's manual supplied
with the unit. VFDs are located in the
main control center.
FX05 Furnace Controller
Present only if an indirect gas-fired furnace option is
present.
The FX05 furnace controller
will display an alarm condition
if present. The controller
will be found in the furnace
control center. See the furnace
Installation, Operation and Maintenance manual and the
controller manufacturer's unit-specific manual for further
information.
®
Troubleshooting - Rotation Sensor
When the unit is first turned on, the LED on the back of
the sensor should turn on and stay on with the wheel
running.
1. When the wheel is spinning, the contact in the
rotation sensor is closed and the small LED light on
the sensor in ON.
2. When the wheel is stopped there is a 10-20 second
delay before the sensor will indicate no rotation.
When the sensor indicates no rotation, it opens the
internal contact and the LED light of OFF.
3. If the LED comes on and then shuts off after
5 seconds or less, the sensor is NOT properly
set. Contact manufacturer for adjustment
procedure.
4. If the LED comes on and then shuts off after 10-20
seconds, the sensor is properly set although it is
either to close to the wheel or not close enough.
It should be 4 mm from the wheel. Verify that the
sensor depth was set using the appropriate gauge.
When the wheel is unplugged and the unit is still
powered on:
1. The LED should stay on for 10-20 seconds and then
turn off.
Troubleshooting - Digital Scroll
Compressor Controller (PDX Only)
The Fault Code chart is printed on the back of the
controller. Note that if the controller generates either a
Code 2 or a Code 4 Lockout, a manual reset must be
performed. Manual Reset is accomplished by shutting
off main power to the unit and then turning it back on.
Digital Compressor Controller Fault Codes
Alert System
Code Condition
Code 2* High discharge
temp trip
Code 3 Compressor
protector trip
Code 4* Locked rotor
Code 5 Demand signal
loss
Code 6 Discharge
thermistor fault
Code 7 Future
Code 8 Welded
contactor
Code 9 Low voltage
* Protective faults that require manual reset
Energy Recovery Ventilator with Heating and Cooling General Description - NOT model specific
Diagnostic Action
Alert Light
Blinks 2 times Lockout
Blinks 3 times Lockout
Blinks 4 times Lockout
Blinks 5 times Lockout
Blinks 6 times Reduce
capacity
N/A N/A
Blinks 8 times Unload
compressor
Blinks 9 times Trip
compressor
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