Hitachi RAC-25WPB Service Manual page 118

Effects of other Checking points
electrical products ・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.
Sharing Checking points
a grounding ・Check for effects of electrical noises coming into the air-
conditioner through grounding wires.
・Check if the grounding works is for the air-conditioner alone or
shared with other equipment. If there is any equipment that
shares it, turn on and off that equipment and detach and
reattach the power plugs and examine their effects on the
reception of remote control signals.
Actions proposed
・Establish an independent grounding for the air-conditioner.
Effects of radio Checking points
・Using a wireless transmitter near the air-conditioner may affect the reception of remote control signals.
waves
・Have your users try sending signals with a wireless transmitter and examine their effects on the
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.
Effects of direct Checking points
・Direct sunlight and other intense light make the remote control light-receiving unit less sensitive.
sunlight
・Check for any time zone where the remote control light-receiving unit of the indoor unit is affected by
direct sunlight depending on the location of the sun and mirror reflection.
Actions proposed
・Block the sunlight to protect against direct sunlight.
118
Air-conditioner
Other
equipment
Grounding