Envision Peripherals Geothermal Indoor Split Heat Pumps - Manual (Page 10)

10
ENVISION SERIES INSTALLATION MANUAL
Open Loop - Well Water Systems
Typical open loop piping is shown below. Always maintain water pressure in the heat exchanger by placing water con-
trol 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 flow through the unit by checking pressure drop across the heat
exchanger and comparing it to the figures in the 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 70% of the total
tonnage. Therefore, 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 building 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 depart-
ments to ensure compliance in
your area.
Notes: For open loop/ground-
water systems or sytems that
do not contain an antifreeze
solution, set SW2-Switch #2
to the “WELL” position (Refer
to the table on page 21.) Slow
opening/closing solenoid valves
(type VM) are recommended to
eliminate water hammer.
Figure 4: Typical Split System Application Open Loop - Well Water
Disconnect
Thermostat Wire
From Air Handler
Vibration Absorbing Pad or Air Pad
P/T Plugs
Boiler Drains for
System Flushing
Water Solenoid
Control Valve
Rubber Bladder
Pressure Tank
Lineset
To Air Handler
Flow
Regulator
Shut-Off Valves
Water Out
Water In
From W ell
Acc Com
Acc NC
Acc NO
1
2
3
C
R
P1
P3
SV
Solenoid
Valve
CC-GND
CC
CCHI
Comfort
Alert
Y1
Y2
Logic Board
Violet(3)
Blk(1)
Wht(4)
VM valve
Violet(2)
CC
Figure 9b: Open Loop Solenoid Valve Connection Option
Typical slow operating external 24V water solenoid valve
(type VM) wiring.
Figure 5: Open Loop Solenoid Valve Connection Option
Typical quick operating external 24V water solenoid valve
(type PPV100 or BPV100) wiring.