Open Loop Ground Water Systems - Johnson Controls RJ H Series Installation Operation & Maintenance

Open Loop Ground Water Systems

Typical open loop piping is shown below. Always maintain water pressure in the heat exchanger by placing water control valves at the
outlet of the unit to prevent mineral precipitation. Use a closed, bladder-type expansion tank to minimize mineral formation due to air
exposure. Insure proper water flow through the unit by checking pressure drop across the heat exchanger and comparing it to the figures
in unit capacity data tables in the specification catalog. 1.5-2 GPM of flow per ton of cooling capacity is recommended in open loop
applications. Due to only minor differences in flow rate from low to high, only one solenoid valve should be used. The valve should be sized
for full flow.
Discharge water from the unit is not contaminated in any manner and can be disposed of in various ways, depending on local codes,
i.e. recharge well, storm sewer, drain field, adjacent stream or pond, etc. Most local codes forbid the use of sanitary sewer for disposal.
Consult your local building and zoning departments to assure compliance in your area.
Note: For open loop/groundwater systems or systems that do not contain an antifreeze solution, set SW2-Switch #2 to the "WELL" position
(Refer to the Dip Switch Field Selection table). Slow opening/closing solenoid valves (type VM) are recommended to eliminate water
hammer.
Figure 8: Open Loop Solenoid Valve Connection Option
Typical quick operating external 24V water solenoid valve
(type PPV100 or BPV100) wiring.
C
R
Acc Com
Acc NC
SV
Acc NO
Solenoid
Valve
Note: SW2-3 should be in the Comp "ON" position.
Figure 10: Open System - Groundwater Application
P1
1
P3
2
3
Unit Supply
Aux. Heat Supply
Disconnects
(If Applicable)
Compressor Low Voltage
Line Voltage to Thermostat
Vibration
and Valve
Absorbing Pad
Figure 9: Open Loop Solenoid Valve Connection Option
Typical slow operating external 24V water solenoid valve
(type VM) wiring.
VM valve
CC
Violet(3)
Comfort
Y1
Alert
Y2
Wht(4)
Flexible
Duct Collar
Rubber Bladder
Expansion Tank
Hot Water Generator
Connections
Solenoid
Valve
Drain
Shut Off Valves
(to isolate solenoid
valve while acid flushing)
Strainer
Boiler Drains
P/T Plugs
For HX Flushing
15
RJ SERIES INSTALLATION MANUAL
Violet(2) CC
Blk(1)
CC-GND
CCHI
Logic Board
High Speed
SV
Flow Control
Valve
(on outlet of
Solenoid Valve)
Water Out
Water In
Shut Off Valves