Problems With Noise And Radio Interference - Sanyo SAP-KMV91G-S Technical & Service Manual

11-5. Problems with Noise and Radio Interference

Since an inverter-type air conditioner works at high frequency under pulse control, it can be affected by external
noise and may also generate interference to nearby radio equipment. For this reason, this air conditioner is fitted
with an electrical noise filter, so no trouble should arise in normal use. However, problems with noise or radio
interference may still occasionally occur depending on where the air conditioner is installed. Take careful note of
the following points.
11-5-1. Problems with Electrical Noise
External noise, such as high-frequency signals, become superimposed on the signal wiring. This may affect
the signal pulse, resulting in a malfunction of the air conditioner.
Places subject to noise problems
1. Areas near broadcasting stations
where strong radio waves are gen-
erated.
2. Areas near a ham radio operator.
3. Areas where high-frequency
sewing machines or arc-welding
equipment are used.
11-5-2. Radio Interference
The air conditioner contains a microcomputer and a compressor which perform switching operations at high
speed. This generates electrical noise. If this noise escapes from the unit or gets into the wiring, interference
to nearby radio equipment such as a television or radio may occur.
Possible noise conditions
1. A television or radio is near the air
conditioner or its wiring.
2. The antenna cable for a television
or radio is near the air conditioner
or its wiring.
3. The signal received from a televi-
sion or radio station is weak.
Symptoms
In such a case, the following symptoms
may occur:
1. The air conditioner stops during
operation
2. Indicator lamps flash
Symptoms
1. Television screen is disrupted by
noise or the image is distorted.
2. Radio programs are affected by
crackling noises.
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Remedy
Ensure that the signal wiring is not
affected by electrical noise.
Isolate the noise or separate the signal
wiring from the noise source.
1. Adopt shielded wiring.
2. Separate the air conditioner from
the noise source.
Remedy
1. Use another power outlet.
2. Keep radio equipment and antenna
cables 1 meter or more from the air
conditioner and its wiring.
3. Replace the antenna with a high-
sensitivity antenna.
4. Replace the antenna cable with
coaxial cable.
5. Install a noise filter (for radio equip-
ment).
6. Install a booster.