17
E2 Controller Trip Set Points and Actions (ZX-MT and ZXL-LT Units)
continuation
Fault Type
Trip Set Point
E2 Control Actions
Auto Resets
Possible Error And Solution
Discharge Gas
Overheat
Discharge
Temperature Over
132°C
- Stop the unit
- Display DLT trip on diagnostic
- Display waiting to restart on diagnostic
-Auto start the unit after 3 minutes
- Lockout unit if 6 trips in less than 1 hour
- Display DLT overheat lockout on
diagnostic
- Initiate Buzzer/ Dialer Relay
5 Auto starts in
1 Hour
- Check if liquid line sight glass is
full;
- Check whether EXV is functioning
and connected to control board
Over Current
Set Based On
Compressor
- Stop the unit
- Display over current trip on diagnostic
- Display waiting to restart on diagnostic
-Auto start the unit after 3 minutes
- Lockout unit if 6 trips in less than 1 hour
- Display over current lockout on
diagnostic
- Initiate Buzzer/ Dialer Relay
5 Auto starts in
1 Hour
- Check rotary switch, make sure it
is on the right position according
to unit model;
- Check oil level through
compressor sight glass (Low temp
unit only);
Electrical Failure
Compressor not
drawing current
after compressor
contactor
organized
- Display compressor protector trip on
diagnostic
- Initiate Buzzer/ Dialer Relay -Auto start
when protector reset, turn off buzzer/
Dialer
Auto start
-Check whether contactor is pulled-
in. If not, check wiring of contactor
coil;
-Check wiring, make sure
compressor is connected to
contactor, and is powered;
-Compressor motor thermal
protector trips, wait till it reset.
Compressor
Rapid Cycling
Minimum 3
minutes OFF time
between starts
-Delay comp start, if minimum off time is
less than 3 min
-Display about to turn on diagnostic
Auto start
-Compressor start signal is active
when unit just stops; the only thing
needed to do is to wait until unit
starts.
Discharge Line
And Coil In Tem-
perature Sensors
Failure
A) Actual
DLT>160°C
(B) DLT Sensor fails
and Actual DLT>
80°C
(C) Both coil-in
and DLT sensor fail
(short circuit)
(D) Coil in sensor
fails(short) and
actual DLT<73°C
(Only Low Temp Unit)
-Stop the unit
-Display DLT sensor failure on the
diagnostic
-Display waiting to restart on diagnostic
-Auto start the unit after 3 minutes
-Lockout unit if 6 trips in less than 1 hour
-Display DLT sensor failure lockout on
diagnostic
-Initiate Buzzer/ Dialer Relay
5 Auto start in
1 Hour
-Check if liquid sight glass is full. If
not, system must have leakage at
somewhere;
-Check whether DLT sensor is
connected to control board;
-Check whether DLT sensor is OK. If
not, replace it with a good one;
-Check whether Coil In sensor is OK.
If not, replace it with a good one
(Only Med Temp Unit)
-Display DLT sensor failure on diagnostic
-Continue to run the unit on default
mode
Run
(A) Coil in sensor
fails(open) and
actual DLT<73°C
(B) Both coil-in
and DLT sensor fail
(open circuit)
(Both Low and Med Temp Unit)
-Display DLT sensor failure on diagnostic
-Continue to run the unit on default
mode
Run
-Check whether the sensors are
connected to control board;
-Check whether Coil-in is OK. If not,
replace it with a new one;
-Check whether compressor is
having excessive flood back.
Ambient Tem-
perature Sensor
Failure
Ambient sensor
reads <-30°C or
>63°C
-Display ambient temp sensors failure on
diagnostic
-Continue to run the unit on default
mode
Run
-Check whether actual Ambient
temperature is out of range;
-Check whether Ambient sensor is
OK and connected to control board.
Condenser
Mid-Coil Sensor
Failure
Mid coil sensor
reads <-30°C or
>63°C
-Display mid coil temp sensors failure on
diagnostic
-Continue to run the unit on default
mode
Run
-Check whether actual mid-coil
temperature is out of range;
-Check whether mid-coil sensor is
OK and connected to control board.
PHE Vapor In
Sensor Failure
(Only Low Temp
Unit)
Vapor In sensor
reads <-16°C or
>73°C
-Display sensor error on diagnostics
-Continue to run the unit on default
mode
Run
-Check whether actual temperature
is out of range;
-Check whether the sensor is
connected to control board;
-Check whether the sensor is
mounted at the right position;
-Check whether the sensor is in heat
isolation material;
-Check whether the sensor has
failed.
PHE Vapor Out
Sensor Failure
(Only Low Temp
Unit)
Vapor out sensor
reads <-16°C or
>73°C
-Display sensor error on diagnostics
-Continue to run the unit on default
mode
Run
