Honeywell TrueFRESH ERV/HRV Série Guide D'installation page 39

Troubleshooting (continued)
Problem
• HRV/ERV
operating
only on high
speed, no
communication
between unit &
wall controls.
• HRV/ERV
supply or
exhaust fan
runs only on
high.
• Motor not
functioning.
• Motor failure.
• Yellow blinking
LED on speed
controller.
TrueFRESH™ ERV/HRV Ventilation Systems 69-2480EF—13
Possible Cause or Test Procedure
Symptom
• Dehumidistat of •
the wall controls
activated. •
• T-3 Timer 20/40/60
mins. activated. •
• Short circuit
between G & •
R terminals of
REMOTES on
Speed Control™.
• Faulty wire between
control and H/ERV.
• Faulty wall control.
• Failure to the HVC •
or LVC PCB board.
• Wire connection or – Test the motor resistance
wire sequence not
corresponding to
wiring diagram.
• Run capacitor failure – Then proceed to measure the
•
•
•
•
• Defrost Thermister •
not properly
connected to HVC •
Controller
• Defrost Thermister
is defective
•
Disconnect all wall controls
from unit
Ensure all other wall controls
are not in override mode.
Inspect the wires to insure not
damage.
Remove wall control and verify
it at the H/ERV.
Resistance test: Unplug H/ERV
unit and with a multimeter
(BLUE & BLACK wires) of the
motor. The range should be
between 33-39 Ohms
resistance (BLUE & BROWN
wires) the range should be
between 56-64 Omhs
If resistance falls within the
above ranges the motor is good.
If capacitor is swollen or
disfi gured, it is defi nitely bad.
Check amperage in leads
going to capacitor when in
operation. If capacitor is open,
no amperage will fl ow.
Remove from circuit and check
for short circuits or grounds
(use ohmmeter only).
Ensure proper connection of
thermister.
Remove access panel to
expose HVC controller verify
defrost thermister is connected
to the "T2" terminal on HVC
controller.
Unplug defrost thermister
from HVC controller & check
readings with Ohm meter.
Solution
• Ensure all wall controls
and Speed Control wire
connections correspond
to their matching letters
• Ensure no nails, staples
or screws are shorting
out the wires.
• Replace LVC PCB
board, wall control and
wires.
• Replace the HVC or LVC
Board
• Correct faulty connection
or wire sequence to
correspond to the wiring
diagram.
• Replace the run
capacitor and/or Motor
• If defrost thermister
is not connected,
please plug-in on
HVC controller on the
terminals marked "TEMP
SENSOR".
• Connect the Ohm meter
to red terminal and if
receive no readings
0, replace defrost
thermister.
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