5
G
Install the indoor unit more than 3.3' (1 m) away from any
antenna or power lines or connecting wires used for tele-
vision, radio, telephone, security system, or intercom.
Electrical noise from any of these sources may affect
operation.
G
install in a sturdy manner to avoid increased operating
noise.
2-2. Embedding the Tubing and Wiring
G
Before beginning embedding installation work, consult
fully with agencies or offices related to the building’s
foundation, construction, electricity, and water.
G
Wait to make connections to the embedded portion.
Each connection step is described later in this
manual.
G
Securely cover the end of the embedded tubing to
prevent intrusion of dirt or moisture.
G
If an embedded tube is to be left for a long time, fill
the tube with nitrogen and seal both ends securely.
If a tube is left open for an extended time, moisture in
the air inside the tubing may condense into water
droplets, and lead to water contamination of the refrig-
erant circuit.
G
In order to prevent insulation breakdown and ground
faults, do not allow wiring ends to come in contact with
rainwater, or be subjected to condensation or dew.
G
Apply sufficient thermal insulation to the refrigerant
tubing and drain pipes.
Table 3
*
If total tubing length becomes 150 to 200 ft. (Max.) or 150 to 230 ft. (Max.), charge additional refrigerant (R410A) by 0.22 oz./ft.
No additional charge of compressor oil is necessary. For more detailed charging information, refer to the Technical & Service Manual.
Max.
Max. Allowable Total
Limit of
Limit of Elevation
Required Amount
Allowable
Tubing Length Total Tubing Length
Difference of
Additional
Model
Tubing Length
at shipment
(L1+L2+L3) or
(H1, H2, H3, H4)
Refrigerant
per unit
(L1+L2+L3) or
(L1+L2+L3+L4)
(ft.)
(oz./ft.)
*
(ft.)
(L1+L2+L3+L4)
(ft.)
(ft.)
CMH1972
82
150 (L1+L2+L3)
150 (L1+L2+L3)
50
—
CMH2472
82
150 (L1+L2+L3+L4)
200 (L1+L2+L3+L4)
50
0.22
CMH3172
100
150 (L1+L2+L3+L4)
230 (L1+L2+L3+L4)
50
0.22
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