GVZC20 Service Manual

SERVICING
42
TROUBLESHOOTING-INDOOR UNIT FOR EEV APPLICABLE UNIT
error.
“ * * “ “ _ _ “
No display
(0.5sec.)
“ _ E “ “ _ _ “
“ * * “ “ _ _ “
Error
(2sec.)
“ _ A “
“ _ _ “ “ * * “
“ _ _ “
“ * * “ “ _ _ “
digit 7 segment displays on indoor control board
State code
(2sec.)
No display
(0.5sec.)
Error code
(2sec.)
No display
(0.5sec.)
(2sec.)
No display
(0.5sec.)
Upper 2-digit of
CFM (2sec.)
Lower 2-digit of
CFM (2sec.)
No display
(0.5sec.)
No display
(0.5sec.)
2-digit 7 segment displays
2.
"A...12...40...".
1. State
2. Error code
2. When the unit is havingsome majorerrorcode in normalmode,2-digit7 segment displays keep
showing error code.
indoorunit. In the event
indoorunit error code to solve the
For example, if the CFM is 1240CFM,7 segmentdisplay shows
show current status of state, error code and airflow.
7 Segment LED
Display (State)
(No Display)
INTERNAL CONTROL FAULT/NO POWER
On
FC
FH
_F
H1
H2
dF
Hu
ELECTRIC HEAT LOW (Hea t Dema nd, Back-up
Heat Demand)
ELECTRIC HEAT HIGH (Heat Demand, Back-up
Heat Demand)
HUMIDITY RUNNING WITHOUT HEATING
(Humidificat on Demand)
Description of Condition
STANDBY, WAITING FOR INPUTS
FAN COOL-COMMUNICATING MODE ONLY
(Aux Heat Demand)
FAN HEAT-COMMUNICATING MODE ONLY
(Aux Heat Demand)
FAN ONLY (Fan Demand-Manual)
DEFROST COMMUNICATING MODE ONLY