Glycol Piping; Table 13 Room Dew Point Temperatures - Emerson Liebert Challenger 3000 Installation Manual

5.4

Glycol Piping

CAUTION
!
Galvanized pipe must not be used in or with systems or units that contain glycol. The
phosphates in the inhibitor can react with the zinc in the galvanized pipe, precipitating an
insoluble material that can eventually foul the system.
CAUTION
!
To help prevent piping failures, supply and return lines must be supported in a way that
keeps their weight from bearing on the piping of the unit, drycooler or pumps.
CAUTION
!
To avoid the possibility of burst pipes, it is necessary to install a relief valve in the system.
This valve may be obtained from the supplier as an option or obtained from another
vendor.
CAUTION
!
Fluid cooled condensers have small internal flow passages. To avoid clogging and other
resulting system operation problems, install a 16-20 mesh filter in the fluid supply line to
the indoor unit. The filter should be located where it can be easily serviced or replaced.
CAUTION
!
Do not install unit on open loop systems. Debris carried by the fluid will clog the brazed
plate condenser.
It is recommended that manual service shut-off valves be installed at the supply and return connec-
tions to each unit. This enables routine service and/or emergency isolation of the unit. In addition,
multiple pump packages require a check valve at the discharge of each pump to prevent back flow
through the standby pump(s).
To facilitate filling, installation of hose bibs at the lowest point of the system is recommended.
Consideration of the minimum glycol temperature to be supplied from the drycooler will determine if
the need exists to insulate the glycol supply and return lines. Insulation will prevent condensation on
the glycol lines in low ambient conditions.
All fluid piping must comply with local codes. Care in sizing pipes will help reduce pumping power
and operating costs.
Table 13 Room dew point temperatures
Dry Bulb
°F (°C)
70 (21.1)
70 (21.1)
72 (22.2)
72 (22.2)
75 (23.8)
75 (23.8)
* Minimum glycol temperature before condensation will occur.
Wet Bulb Relative
°F (°C) Humidity
57.2 (14.0) 45
58.5 (14.7) 50
58.9 (24.9) 45
60.0 (15.5) 50
61.2 (16.2) 45
62.5 (16.9) 50
Dew Point*
°F (°C)
48.0 (8.9)
50.5 (10.3)
50.0 (10.0)
52.4 (11.3)
52.4 (11.3)
55.0 (12.7)
31
Glycol/GLYCOOL Cooled Models