Mitsubishi Electric CITY MULTI PUHY-P108 Service Handbook page 252

Error definition and error
Error Code
1500 Refrigerant An error can be detected
overcharge by the discharge temper-
ature superheat.
1. If the discharge SH
10K [18°F] or less is
detected during oper-
ation (the first detec-
tion), the outdoor unit
stops at once, turns to
anti-restart mode for 3
minutes, and restarts
after 3 minutes auto-
matically.
2. If the discharge SH
10K [18°F] or less is
detected again within
30 minutes after first
stop of the outdoor
unit (the second de-
tection), the outdoor
unit will make an error
stop, and the error
code "1500" is dis-
played.
3. If discharge SH 10K
[18°F] or less is de-
tected more than 30
minutes after the out-
door unit stops, and
the operation de-
scribed in step 1
above will start.
4. For 30 minutes after
the stop of the outdoor
unit, preliminary errors
will be displayed on
the LED display.
2500 Water leakage When the drain sensor
detects water or its tip be-
comes immersed in wa-
ter.
detection method
(1) Overcharged refrigerant
(2) Thermistor input circuit
failure on the main board
(3) Faulty mounting of ther-
mistor (TH11, TH12)
Water leakage due to problems
with such equipment as a hu-
midifier
- 243 -
Cause Check method and remedy
Refer to the page on refrigerant
amount evaluation.
Check the temperature and the pres-
sure of the sensor with LED monitor.
Check for water leakage around the
humidifier and clogging of outlet of
the drain pan.
[ IX Troubleshooting ]