AUX ASW-H09B5B4/FAR3DI-C3, Service Manual

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47
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16
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F7-OVP or UVP error
Explanation of
error
Cause: All the inverter air conditioners are equipped with voltage
inspection circuits, but differnt models of machines have differnt
locations for the voltage inspection (on the modue panel or Outdoor
Unit main PCB). When the supply voltage is lower than 135V or
higher than 275V, the inspectio circuit would detect over or under
voltage protection signal and send it to the Outdoor Unit main PCB
and the Outdoor Unit main PCB would raise the alarm "OVP or UVP
error" and indicate it through the Indoor Unit motor.
Inspection path: supply voltage → Indoor Unit direct current voltage
→ reactor wiring → module panel → Outdoor Unit main PCB.
Tools required
for inspection
Multimeter
Frequent
problematic part
Supply voltage, reactor, moduel panel and Outdoor Unit main PCB.
Inspection
procedure and
key points
1. First, check the supply environment of the user, especially shall
check when the compressor of the air conditioner has been running for
a while. The normal supply voltage shall be between 198V and 242V
and the minimum work assurance range of the air conditioner shall be
within 165V and 265V and it shall be especially noted that the voltage
value shall not be decreased significantly after running of the
compressor (voltage decreasing by over 25V), because if the supply
voltage is decreased by a lot, it means the supply line capacity is
insufficient and the user is usually suggested to replace the circuit or
install a specizlied air conditioner supply voltage stabilizer.
2. For the Outdoor Unit machines with PFC panels (without separate
rectifier bridges), the operator shall ensure if the PFC function is on
with the direct current voltage grade of the multimeter. When the
compressor is running, voltage between P and N ends detected on the
test module panel or Outdoor Unit main PCB shall be over 200V and if
the voltage is below that range, it is possible that the reactor is faulted
or the PFC is broken.
3. When the air conditioner is switched on, if the compressor is not
running but there is a alarm of "OVP or UVP error" and the power
voltage detected with the multimeter is not below 150V, it's probably
the voltage inspection circuit is faulted. The operator shall check and
confirm the voltage inspection circuit is on which PCB first and then
replace it. The regular replacement: for the Outdoor Unit machine of
single panel single chip, replace the Outdoor Unit controller directly;
and for the machine of two panels, replace the module panel.
Special attention
For some models, OVP or UVP error signal is delivered through the
connector wires between the module panel and the Outdoor Unit main
PCB, thus it is possible the voltage signal is not delivered when the
communication between teh module panle and the Outdoor Unit main
PCB is not good. It is possible that the error is fause raised but after
some minutes that the error is finally confirmed as "Outdoor Unit main
PCB and module pannel communication error", which shall be
specially noted.