Mitsubishi Electric City Multi CMB-P1016NU-G, Service Handbook

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[
IX
Troubleshooting ]
2500 Water leakage Detection of water im-
mersion of drain sensor
while the drain pump is
stopped
(1) Water leakage due to de-
terioration of the elements
of the humidifier with a wa-
ter permeating filter.
(2) Water leakage due to
poorly seated solenoid
valve
(3) Water leakage due to inap-
propriately connected feed
water tube
(4) Water leakage from the re-
lief valve of the solenoid
valve due to a rise in feed
water pressure
1) Check the error history.
Rate of occurrence
*If the same problem is experi-
enced by other units during the
same period, water leakage from
the relief valve of the solenoid
valve due to deterioration of hu-
midifying element, variation in
feed water pressure, or foreign
objects in the valve is suspected.
2) Find the location of water leaks.
ΠHumidifier elements
Replace the humidifier elements
that have completed the product
life cycle.
ΠSolenoid valve relief valve
If water is always leaking out of
the relief valve while the humidifi-
er solenoid valve is set to ON, the
valve may not be seated correct-
ly. Replace the solenoid valve.
Check and clean the built-in
strainer on the feed water valve
near the unit, and make sure the
valve is properly seated.
ΠTube connection
Repair water leaks.
3) Checking the water supply method
ΠIs water supplied by a pump or
from the elevated reservoir?
*If water is supplied by a pump,
water may leak out of the relief
valve because of the temporary
rise in feed water pressure above
the allowable range.
ΠCheck the feed water pressure.
Allowable range:
0.049-0.686MPa[7-99psi]
(0.5-7.0kgf/cm
2
)
Install a pressure-reducing valve
if the pressure exceeds the allow-
able range.
4) Unknown
*If water is supplied from an ele-
vated reservoir and there is no
possibility of water pressure vari-
ation, poor water quality (clogged
solenoid valve) is suspected as
the cause of the problem. Al-
though replacement of the sole-
noid valve may temporarily
relieve the problem, the source of
the problem should be eliminated
if the problem is also experienced
by other units.Check the water
quality, and make sure it is con-
taminants free.
*If no trace of water is left on the
drain pan, drain sensor malfunc-
tion is suspected. If a heating op-
eration was performed after the
error was detected, it is possible
that the water in the drain pan has
evaporated. Replace the drain
sensor only if it can be deter-
mined that the empty drain pan is
not due to evaporation.
<Error resetting method>
Reset (error reset) the indoor unit in
trouble with the remote controller.
Error Code
Error definition and error
detection method
Cause Check method and remedy