Hitachi RAC-25WSE, Service Manual

Page: 117 / 142

Checking points
·
Direct sunlight and other intense light make the remote control light-receiving unit less sensitive.
·
Check for any time zone where the remote control light-receiving unit of the indoor unit is affected by
ǂ
direct sunlight depending on the location of the sun and mirror reflection.
Actions proposed
·
Block the sunlight to protect against direct sunlight.
Checking points
·
Using a wireless transmitter near the air-conditioner may affect the reception of remote control signals.
·
Have your users try sending signals with a wireless transmitter and examine their effects on the
ǂ
reception of remote control signals.
Actions proposed
·
Add a ferrite core to the power cord and F cable.
·
Add a ferrite core to the internal wiring of the indoor unit.
·
Move the wireless antenna.
Checking points
·
Check the effects of light and power noises coming from other electrical products.
·
Turn on and off the electrical products, turn off the power and turn on the power, and check their effects
on the reception of remote control signals.
·
For products whose operating states change, check the effects of each state.
Actions proposed
·
Change the location relationship between the air-conditioner and the target products.
·
Use a different wall outlet for the target products.
Checking points
·
Check for effects of electrical noises coming into the air-
ǂ
conditioner through grounding wires.
·
Check if the grounding works is for the air-conditioner alone or
ǂ
shared with other equipment. If there is any equipment that
ǂ
shares it, turn on and off that equipment and detach and
ǂ
reattach the power plugs and examine their effects on the
ǂ
reception of remote control signals.
Actions proposed
·
Establish an independent grounding for the air-conditioner.
Effects of other
electrical products
Sharing
a grounding
Air-conditioner
Other
equipment
Grounding
Effects of radio
waves
Effects of direct
sunlight
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