Open Loop Well Water Systems - Trane 2GN Series Installer's Manual

OPEN LOOP WELL 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. Ensure proper water fl ow
through the unit by checking pressure drop across the heat
exchanger and comparing it to the fi gures in the unit capacity
data tables in the specifi cation catalog. Usually 1.5-2 GPM of
fl ow per ton of cooling capacity is recommended in open loop
applications. In dual capacity units, stage 1 is 70% of the total
tonnage. Therefore, due to only minor differences in fl ow rate
from low to high, only one solenoid
valve should be used. The valve
should be sized for full fl ow.
Discharge water from the unit is not
contaminated in any manner and
can be disposed of in various ways
depending on local building codes (i.e.
recharge well, storm sewer, drain fi eld,
adjacent stream or pond, etc.). Most
local codes forbid the use of sanitary
sewer for disposal. Consult your local
building and zoning departments to
ensure compliance in your area.
Figure 5: 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
18-GL07D1-4
Figure 4: Typical Split System Application Open Loop - Well Water
Thermostat Wire
From Air Handler
Disconnect
Vibration Absorbing Pad or Air Pad
P1
1
P3
2
3
Notes: For open loop/groundwater systems or sytems that do
not contain an antifreeze solution, set SW2-Switch #2 to the
"WELL" position (Refer to the DIP Switch Settings table.) Slow
opening/closing solenoid valves (type VM) are recommended
to eliminate water hammer.
Rubber Bladder
Pressure Tank
Lineset
T o Air Handler
Water Solenoid
Control Valve
Boiler Drains for
System Flushing
Flow
Regulator
Shut-Off Valves
P/T Plugs
Figure 9b: Open Loop Solenoid Valve Connection Option Wiring
diagram for dual water valve installations, one type V slow operating
solenoid and one BPV100/PPV100 quick operating solenoid.
C
W/Y
CC
Compressor
Contactor
Taco Valve
Coil
2GN SPLIT INSTALLER'S GUIDE
Water Out
Water In
From W ell
CCG or CC GND
CC
CC2 or CCHI
SV
BPV/PPV
Solenoid
Logic Board
11