Sanyo SPW-U255H - Page 456

5-10
5
SPW-C256/366VH
(2-1) [Alarm "P26"]
No
Start of defect diagnosis
Is the power voltage correct?
Improve the power voltage line.
Check the following:
Check to ascertain that the power voltage is within the permissible range of 198 to 264V
for indoor and outdoor units regardless of whether the compressor is operating or not.
* Pay special attention to whether the voltage drops after compressor operations while
measuring.
No
No
No
Repair the wiring connectors.
Compressor's wiring connector
3P : white
Tighten the screws  rmly.
Abnormal temperature rise in the HIC control mounted on the outdoor unit control PCB is prevented
by radiating the heat, with the heat sink being attached  rmly to the HIC control.
The HIC control mounted on the outdoor unit control PCB cannot radiate properly if the
screws are loose. Consequently, the temperature inside the HIC control can rise abnormally
and the alarm P26 occurs.
Operating on high load.
Recovery methods differ in accordance with the cause.
• Recharge refrigerant
• Replace the thermistor
• Repair the pipes, etc.
1. Potential Causes
• Refrigerant overcharge
Has the refrigerant been overcharged?
*Verifying Overcharge
There is no problem if the difference between the temperature on the indoor unit "E2" and the
saturated temperature of the outdoor unit's gas pipe service valve pressure is within 2 during
the heating mode. Any of the following could be the reason if the former is two or more degrees
lower than latter.
• Faulty operations of the outdoor unit electronic expansion valve.
• Pipe blockage, crushed pipes, etc.
(Assumed to be on the liquid pipes during the cooling mode and the gas pipes during the
heating mode.)
• C1 and C2 thermistor error on the outdoor unit (during the cooling mode.)
• E1 and E2 thermistor error on the indoor unit (during the heating mode.)
2.Temperature on the high-pressure side during normal operations.
Cooling: Temperature of the C2 thermistor on the outdoor unit is approximately between 45 and
55 .
Heating: Temperature of the E2 thermistor on the indoor unit is approximately between 40 and
50 .
* There are cases in which the above temperatures will be lower depending on the operation
conditions.
No (Abnormal resistance value)
Replace the outdoor unit control PCB.
• Veri cation method
Measure the resistance at all areas on the HIC control mounted on the outdoor unit control PCB.
Refer to the page 5 - 12.
Replace the outdoor unit control PCB if the readings are below permissible values.
No (Defective insulation)
Replace the compressor.
• Potential cause:
Insulation failure caused by the compressor lock.
• Veri cation Method
Remove the wires from the connectors on the top of the compressor. Measure
the insulation resistance of the U, V and W phases and con rm that they are
1M or more.
Are the
compressor wiring
connector and U/V/W connections
on the compressor
terminal
OK?
Is the heat
sink connected properly
to the HIC mounted on
outdoor unit control
PCB?
Is the high-pressure
for the refrigerant cycle within
the range? (High load
operating?)
Are the resistance
values permissible at all
areas in HIC mounted on
outdoor unit control
PCB?
Is the insulation on the
compression OK?
Replace the outdoor unit control PCB.
Yes
Yes
Yes
Yes
Yes
Yes
(No problem
on tightening)
(Not operating
on high load)
(No problem with
the resistance value)
(No problem with
the insulation)
Excessive current alarm of HIC Control Mounted on Outdoor Unit Control PCB
Related parts
• Outdoor unit control PCB (Model 256 : CR-C256VH)
SM830160-03ClassicPAC-iA4.ind1010SM830160-03ClassicPAC-iA4.ind1010 2010/02/1610:30:062010/02/1610:30:06