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Operation and Maintenance Instructions
THE NEW EcoHeater
DSEH180401.00.EN
Continuous product development may give rise to specification changes without notice.
6 Troubleshooting
6.1 Troubleshooting in the event of an alarm
The alarms for the refrigerant circuits are presented on the step switch display:
see "2.2 Function" on page 8. Alarms may, for example, be generated by the
high pressure switch and frequency inverter. To ascertain what has caused the
alarm, follow the procedure below.
Inspection
Possible cause
Corrective action
Is the alarm
“94 Drive offline”displayed?
YES
⇒
The frequency inverter does not
have supply voltage 3×400V
Check the supply voltage to the frequency
inverter
Check fuses
Check cabling for communication between
frequency inverter and Carel
NO
⇓
Has the high pressure switch
tripped?
Is the alarm
"121 Compr 1, High pressure
switch"
or
"180 Compr 1,
High pressure switch"
displayed?
YES
⇒
No or too low flow of water
across the condenser
Defective high pressure switch
Check the flow of water across the
condenser
Reset the pressure switch manually
Check/replace
NO
⇓
Is the alarm
”118 Compr 1,
Low evaporation pressure”
displayed?
YES
⇒
Insufficient refrigerant volume
Look for leakage, seal the leak and top up
with refrigerant
No or too low air flow across
evaporator
Check/adjust the flow
Defective expansion valve
Check/replace
NO
⇓
Is the LED flashing red on the
frequency inverter?
YES
⇒
Phase failure/voltage failure
Check the 3-phase supply, measure the
incoming voltage.
Reset the frequency inverter by switching
off the voltage for 1 minute or more. Check
that the compressor is running without
dissonance.
Overload/defective stepless com-
pressor
Reset the frequency inverter by switching
off the voltage for 1 minute or more. Check
that the compressor is running without
dissonance.
NO
⇓
Is the alarm
"AL 120 Compr 1
Low pressure diff." dis-
played?
YES
⇒
No pressure difference between
the high-pressure and low-
pressure side
Contact service
NO
⇓
Is the alarm
"AL 59 Compr 1
Low Cond Temp" displayed?
YES
⇒
Condensation temperature too
low
Contact service
