JOHNSON CONTROLS
19
SECTION 2 - INSTALLATION
FORM 160.75-N1
ISSUE DATE: 04/15/2019
2
Condenser Water Circuit
For proper operation of the unit, condenser refrigerant
pressure must be maintained above evaporator pres-
sure. If operating conditions will fulfill this require-
ment, no attempt should be made to control condenser
water temperature by means of automatic valves, cy-
cling of the cooling tower fan or other means, since
chillers are designed to function satisfactorily and ef-
ficiently when condenser water is allowed to seek its
own temperature level at reduced loads and off-peak
seasons of the year. However, if entering condenser
water temperature can go below the required mini-
mum, refer to Unit Operation and Maintenance (Form
160.75-O1); condenser water temperature must be
maintained equal to or slightly higher than the required
minimum. See Figure 8 on page 18 for typical water
piping schematic.
Stop Valves
Stop valves may be provided (by others) in the evapora-
tor and condenser water piping adjacent to the unit to
facilitate maintenance. Thermometer wells and pressure
taps should be provided (by others) in the piping as close
to the unit as possible to facilitate operating check.
Flow Switches
Thermal type water flow switches are factory mount-
ed in the chilled and condensed water nozzles and are
factory wired to the OptiView™ control panel. These
solid-state flow sensors have a small internal heat-
ing element and use the cooling effect of the flowing
fluid to sense when an adequate flow rate has been
established.
Waterbox Drain and Vent Valves
Drain and vent valves (by others) should be installed
in the connections provided in the evaporator and con-
denser liquid heads. These connections may be piped
to drain if desired.
Checking Piping Circuits and Venting Air
After the water piping is completed, but before any
waterbox insulation is applied. Tighten and torque to
maintain between 30 and 60 ft. lbs. (41 and 81 N·m)
the nuts on the liquid head flanges. Gasket shrinkage
and handling during transit cause nuts to loosen. If wa-
ter pressure is applied before tightening is done, the
gaskets may be damaged and have to be replaced. Fill
the chilled and condenser water circuits, operate the
pumps manually and carefully check the evaporator
and condenser water heads and piping for leaks. Repair
leaks as necessary.
Before initial operation of the unit both water circuits
should be thoroughly vented of all air at the high points.
UNIT PIPING
Compressor lubricant piping and system external pip-
ing are factory installed on all units shipped assembled.
On units shipped dismantled, the following piping
should be completed under the supervision of the John-
son Controls representative: (1) the lubricant piping to
oil sump and oil evaporator and system oil return con-
nections using material furnished. Refer to Installation
and Reassembly - Unit (Form 160.75-N3).
To Next Page
Loading...
Need help?
General
