Reznor MASA Unit Installation Manual - Manual (Page 16)

Form I-COND, P/N 220746R6, Page 16
Maximum Spacing Between Pipe Supports for Copper Tubing
Nominal Diameter (OD) 5/8" 7/8" 1-1/8" 1-3/8"
Maximum Span 5 ft (1.5M) 6 ft (1.8M) 7 ft (2.1M) 8 ft (2.4M)
TABLE 5 - Maximum
Spacing between
Pipe Supports
6.0 Mechanical
(cont’d)
6.1.3.6 Brazing Connections
CAUTION
Do not leave system open to the atmosphere any longer
than minimum required for installation. Exposure for more
than five minutes may contaminate the system. POE oil in the
compressors is extremely susceptible to moisture absorption.
Always keep ends of tubing sealed during installation. See
Hazard Levels, page 3.
Brazing materials must be able to withstand the high pressure of R-410A refrig-
erant. A high temperature, silver phosphate type brazing with 5% or greater
alloy is recommended.
To prevent oxidation, purge tubing with 2-3 psig of regulated dry nitrogen while
it is being brazed. Before brazing connections, check the condenser unit for
leaks (See Paragraph 6.2.1). After the unit has been properly leak tested, the
nitrogen remaining in the circuit can be used as part of the purge while braz-
ing. Open the service valve as needed to release the nitrogen. Do not allow
moisture to enter the system.
The installer is responsible for brazing and for complying with appropriate stan-
dard refrigerant piping procedures.
CAUTION
All brazing should be done using a 2 to 3 psig dry nitrogen
purge flowing through the pipe being brazed. See Hazard
Levels, page 3.
CAUTION
Do not open the service valves until after the condenser unit
circuits are leak tested (See Paragraph 6.2.1.) See Hazard
Levels, page 3.
CAUTION
When brazing, protect all painted surfaces and components
from excessive heat. Wet wrap all valves but do not allow
moisture to enter the tubing. See Hazard Levels, page 3.
6.2 Leak Test the
Refrigerant
Circuits
6.1.3.7 Piping Support and Insulation
Comply with piping support spacing requirements in TABLE 5.
Insulate the entire length of each suction line and optional hot gas bypass
line(s). Insulate any portion of the liquid line that is subject to extreme tempera-
ture. To prevent vibration noise, isolate all piping from the building structure or
ductwork.
6.2.1 Leak Test the Condensing Unit
The condensing unit is shipped with a 50 psi nitrogen holding charge in each
circuit. Install gauges to assure that the condensing unit sections of Circuit A are
6.1 Refrigerant
Piping (cont’d)
6.1.3 Refrigerant
Piping Guidelines
(R-410A Refrigerant)
(cont’d)