Insulation; Piping Size - Mitsubishi Electric M-SERIES Installation Manual

• Never use existing refrigerant piping.
• The large amount of chlorine in conventional refrigerant and refrigerant oil in the existing piping will cause
the new refrigerator to deteriorate.
• Store the piping to be used during the installation indoors and keep both ends of the piping sealed until
just before brazing.
• If dust, dirt or water gets into the refrigerant cycle, the oil will deteriorate and the compressor may fail.
• Use ester oil, ether oil or alkylbenzene (small amount) as the refrigerant oil to coat flares and flange
connections before connecting.
• The refrigerant used in the unit is highly hydroscopic and mixes with water which will degrade the
refrigerant oil.

12.1 Insulation

To avoid dew drops, provide sufficient anti-sweating insulation to the refrigerant and drain pipes. When
using commercially available refrigerant pipes, be sure to cover with available insulating material with heat-
resistant temperature of more than 100 °C [212 °F] and thickness given below, on both liquid and gas
pipes. Insulate all indoor pipes with polyethylene insulation with a minimum density of 0.03 and a thickness
as specified in the table below.
Pipe size
6.4 mm to 25.4 mm [1/4 to 1 in.]
28.6 mm to 38.1 mm [1-1/8 to 1-1/2 in.]
• If the unit is used on the highest story of a building and under high temperature and high humidity, it is
necessary to use thicker insulation than specified in the table above
• If there are customer's specifications, please follow them

12.2 Piping size

Model
Liquid pipe
Refrigerant pipe
Gas pipe
Drain Pipe
Specifications are subject to change without notice.
SVZ-KP12,18, 24, 30, 36NA
Insulation thickness
>10 mm [7/16 in.]
>15 mm [5/8 in.]
SVZ-KP•NA
12 18
6.35 mm [1/4]
9.52 mm [3/8] 12.7 mm [1/2]
O.D. 32 mm [1-1/4]
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