Refrigerant Piping Work - Mitsubishi Electric M-SERIES Installation Manual

12. Refrigerant piping work

For constraints on piping length and allowable difference of elevation, refer to the design section of the
engineering manual.
The method of pipe connection on the air handler is flare connection.
Provide proper bracing for refrigerant piping so no load is imparted upon the connections at the air handler.
WARNING
When installing and moving the unit, do not charge it with refrigerant other than the
refrigerant specified on the unit. Mixing of a different refrigerant, air, etc. may cause the
refrigerant cycle to malfunction and result in severe damage.
CAUTION
Use refrigerant piping made of C1220 (Cu-DHP) phosphorous deoxidized copper as
specified in ASTM B280 Standard for copper and copper alloy seamless pipes and tubes.
In addition, be sure that the inner and outer surfaces of the pipes are clean and free of
hazardous sulphur, oxides, dust/dirt, shaving particles, oils, moisture, or any other
contaminant. Never use existing refrigerant piping.
CAUTION
COIL UNDER PRESSURE
Always wear safety glasses when working around pressurized devices. The air handlers
are shipped with a nitrogen holding charge in the coil. Carefully follow these instructions
when releasing the charge.
Carefully remove the flare nut off the end of the pipe to release any gas.
Both refrigerant lines need to be insulated all the way up to the cabinet. Make sure the
openings in the cabinet around the refrigerant lines are sealed. 3/8 in thick insulation is the
minimum recommended thickness. Based on ambient conditions, local codes and line
length, thicker insulation may be desired.
Do not put any oil on the threaded portion of the flare nuts. This may cause the flare nut to
loosen and leak refrigerant.
Specifications are subject to change without notice.
SVZ-KP12,18, 24, 30, 36NA
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