York AFFINITY OptiHeat YAW040 Installation Manual page 8

AFFINITY SINGLE STAGE HYDRONIC WITH OPTIHEAT INSTALLATION MANUAL
Field Connected Water Piping cont.
Open Loop Well Water Systems
Always maintain water pressure in the heat exchanger by
placing water control valves at the outlet of the unit. Use
a closed bladder type expansion tank to minimize mineral
deposits. Ensure proper water flow through the unit by
checking pressure drop across the heat exchanger and
comparing it to the figures in the pressure drop table.
Normally, about 2 GPM flow rate per ton of cooling capacity
is needed in open loop systems, (1.5 GPM per ton minimum if
entering source temperature is above 50°F [10°C].
Some water control valves draw their power directly from
the unit's 24V transformer and can overload and possibly
burn out the transformer. Check total VA draw of the water
valve(s) and ensure it is under 40 VA.
Discharge water from a heat pump 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 restrict the use of sanitary sewer for
disposal. Consult your local building and zoning departments
to ensure compliance in your area.
Typical Open Loop Installation
Load Liquid
Connections
Line Voltage
Shut-off Valve
Disconnect
(to isolate solenoid
valve while acid
flushing)
Figure 1a: Open Loop Solenoid Valve Connection Option
Typical quick operating external 24V water solenoid valve
(type PPV100 or BPV100) wiring.
SV
Solenoid
Valve
NOTE: SW2-4 and SW2-5 should be "OFF" to cycle with
the compressor.
Figure 1b: Open Loop Solenoid Valve Connection Option
Typical slow operating external 24V water solenoid valve
(type V100FPT) wiring.
C
W/Y
V Valve
NOTE: SW2-4 should be "ON" and SW2-5 should be "OFF"
when using a slow opening (V100FPT) water valve.
Rubber Bladder
Expansion Tank
Flow Regulator Valve
Solenoid
Valve
Boiler Drains for
HX Flushing
P/T Plugs
Vibration Absorbing NOTE: Valves and boiler drains must be installed
Mesh or Air Pad so the heat exchanger can be acid flushed.
8
C
P1
R
1
Acc Com
2
Acc NC
3
Acc NO
ABC Board
C
Orange(29)
R
Black/
White(31)
Acc Com
ACC NC
Acc NO
ABC Board
Water Out
Water In
Shut-off
Valve
P2