Mitsubishi Electric PURY-M200YNW-A1 Service Handbook page 427

[8-15 Main-HBC Maintenance Instructions ]
6. Common faults and solution
Please cut off the power supply before removal of the motor junction box and dismantlement
of the pump.
Fault
a)
b)
When the opera-
tion is started, the
c)
motor does not
start.
d)
e)
a)
b)
Uneven water
c)
flow from the
pump
d)
e)
a)
b)
The pump is run-
ning but no water
is pumped
c)
d)
a)
b)
After power-off,
the pump is rotat-
ing in the reverse
c)
direction
d)
a)
b)
Abnormal vibra-
tion and noise in- c)
side the pump
d)
e)
160
- chapter 8
Cause
Power failure
Fuse is broken
Motor is overloaded
INV circuit board failure
The control circuit is failed
The water inlet pipe is too small
No sufficient water at the pump inlet
The liquid level is too low
The inlet pressure is too small com-
paring with the water temperature,
pipeline loss and flow
The water inlet pipe is partially
blocked by impurities
The water inlet pipe is blocked by
impurities
The bottom valve or check valve is
at the Closed position
The water inlet pipe leaks
Air in the water inlet pipe or pump
Water inlet pipe is leaked
The bottom valve or check valve is
failed
The bottom valve is blocked at the
open or partial open position
Air pockets in the water inlet pipe
Water inlet pipe is leaked
The water inlet pipe is too small or
is partially blocked by impurities
Air in the water inlet pipe or pump
The device head is lower than the
pump head
The mechanical parts of pump are
connected
Solution
a) Replace the power supply
b) Replace the fuse
c) Check the system
d) Replace the INV circuit board
e) Check the control circuit
a) Increase the water inlet pipe diam-
eter
b) Improve the system, and try to in-
crease the water volume
c) Try to lift the liquid level
d) Improve the system, and try to in-
crease the outlet pressure
e) Check and remove dirt
a) Check and remove dirty
b) Check the bottom valve and check
valve
c) Check and repair the water inlet
pipe
d) Re-fill water, and discharge air
a) Check and repair the water inlet
pipe
b) Check and repair the bottom valve
and check valve
c) Check and repair the bottom valve
d) Check and repair the water inlet
pipeline and discharge air
a) Check and repair the water inlet
pipe
b) Increase or check and repair the
water inlet pipe
c) Re-fill to exhaust air
d) Improve the system or re-select
e) Check and repair the pump
Remarks
Notes for item
e): The pump
must not be dis-
assembled by
the user.
BS_08_L