Ecoer EODA18H-2436, Service Manual, Page: 31 / 82

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3. Troubleshooting
3.1 Problems without Codes
If the system does not operate properly besides any malfunctions. Check the system based on the
following procedures.
Symptoms Possible causes Solutions
The unit energized but the
digital tube shows nothing
•
See the following page
•
See the following page
System does not start-up
but the digital tube shows
normally
•
No 24 Vac signal from thermostat.
•
Incompatible thermostat.
•
Be sure Y/O/C wirings are connected
correctly (See page 27~34) and the setting
temperature is proper.
•
Use other traditional 24Vac thermostats.
System operates mode
reversely
•
Incorrect O/B signal selection.
•
Choose
O for cooling
from thermostat.
System cannot cool well
•
Outside temperature is too high.
•
Outside temperature is too low.
•
Dirty air filter or blocked outlet of
indoor unit.
•
Too little refrigerant in the system.
•
Refrigerant has been blocked in the
condenser coil.
•
Normal protection control to limit RPS
•
Ensure the cooling loads
•
Replace the air filter and eliminate any
obstacles.
•
Check refrigerant amount or any leaks.
•
Counterclockwise the TXV (Make sure the
refrigerant coefficient is 0.6)
System cannot heat well
•
Outside temperature is too low but no
third-party heat inside.
•
The outdoor coil is dirty or has been
covered by heavy snow.
•
Dirty air filter.
•
Micro channel (MC) coil has been used
•
Lack of refrigerant.
•
Install auxiliary heat for backup *
Dual-
heating
is recommended.
•
Clean the outdoor coil.
•
Replace the air filter.
•
No MC coils shall be used for heat pump.
•
Check refrigerant amount or any leaks.
Y1
Dual-heating
Condensing unit W terminal outputs 24VAC
once ambient temperature is lower than
specified value for auxiliary heating resource
to start. Only available when n02 = 0 (default
ON) and Y signal = ON.
THERMOSTAT
G2 G R C W1 C Y O W
n03 setting
0 (factory): TA<15
°
F (24V output)
1: TA<30
°
F (24V output)
2: TA<40
°
F (24V output)
3: TA<-3
°
F (24V output)
4: OFF (No 24V output)
ONLY AVAILABLE TO ECOER THERMOSTAT
WITH EAHATN-XX AIR HANDLER
NOTES:
1. Be sure power supply agrees with equipment nameplate.
2. Power wiring and grounding of equipment must comply with local codes.
3. Low voltage wiring to be No. 18 AWG minimum conductor.
4. “
” means the electric auxiliary heat connection.
Some thermostats may use W2/AUX for heat pump.
G2
W*
G
RE
EN
RE
D
BL
AC
K/
BR
O
W
N
W
H
IT
E
BL
AC
K
Y
E
LLO
W
OR
AN
GE
W
H
IT
E