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9
E SERIES INSTALLATION MANUAL
Figure 10: Open System - Ground Water Application
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. Usually 1.5-2 GPM of flow
per ton of cooling capacity is recommended in open loop applications. In dual capacity units, stage 1 is half of the total ton-
nage. Therefore, on a E048, the stage 1 solenoid should flow 3-6 GPM and stage 1 & 2 together should flow 6-9 GPM.
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 table on page 18.) Slow opening/closing solenoid valves (type VM) are recommended to elimi-
nate water hammer.
Solenoid Valve
Flow
Regulator
Use two valves for dual capacity units.
Use one valve for single speed units.
Flexible
Duct Collar
Vibration
Absorbing Pad
P/T Plugs
Drain
Desuperheater
Connections
Auxiliary
Heater
Knockout
Low Voltage
to Thermostat
and Valve
Unit Supply
Aux. Heat Supply
Water Out
Water In
Shut Off Valves
Boiler Drains
For HX Flushing
Disconnects
(IfApplicable)
Rubber Bladder
Expansion Tank
Solenoid
Valve
Shut Off Valves
(to isolate solenoid
valve while acid flushing)
Strainer
Flow Control
Valve
(on outlet of
Solenoid Valve)
Compressor
Line Voltage
Figure 9: Open Loop Solenoid Valve Connection Options
Typical single stage external 24V
water solenoid valves (type PPV100
or BPV100) wiring.
Typical dual capacity external 24V
water solenoid valves (type VM)
R C Y1 Y2 W O G LO
Dual Capacity
Logic Board
Y1 From
Thermostat
1
2
3
1
2
3
Y2 From
Thermostat
Taco motorized valve #1
Taco motorized valve #2
CC
CCHI
CCH
CCL
Blk
Dual Capacity
Logic Board
CC GND
CCLO
SV1
Wh
Red
Stage 2
solenoid valve
SV2
Blk
Blk
Typical Two Stage external 24V water solenoid valves
(type PPV100 or BPV100) wiring
Note: switch SW2 - 3 to comp position
C
R
P1
1
Solenoid
Valve
2
ACC Com
2
1
ACC NC
ACC NO
3