Electrical connections, General, Unit power connection – WaterFurnace 7 Series User Manual
Page 13: Accessory relay, 220 volt operation
13
7 SERIES 50Hz 700A11 INSTALLATION MANUAL
General
Be sure the available power is the same voltage and phase
as that shown on the unit serial plate. Line and low voltage
wiring must be done in accordance with local codes or
the National Electric Code, whichever is applicable. The
compressor has no internal overload. The circuit breaker in
the control box is the overload protection for the drive and
the compressor. Bypassing the circuit breaker could result
in damage to the compressor and voiding the warranty.
Unit Power Connection
Connect the incoming line voltage wires to L1 and L2 of
the contactor as shown in Figure 13c for single-phase unit.
Consult the Unit Electrical Data in this manual for correct
fuse sizes.
Open lower front access panel. Remove ground fastener
from bottom of control box (Figure 13b). Swing open
control box (Figure 13a). Insert power wires through
knockouts on lower left side of cabinet. Route wires
through left side of control box and connect to contactor
and ground (Figure 13c). Close control box and replace
grounding fastener before unit startup.
Ground Fastener
must be installed for
proper unit ground
Wire Insert
Location
Figure 13c:
Line Voltage 220-240/50/1 control box
Figure 13b:
Wire access (control box closed)
Figure 13a:
Wire access (control box open)
Electrical Connections
Accessory Relay
A set of “dry” contacts has been provided to control
accessory devices, such as water solenoid valves on open
loop installations, electronic air cleaners, humidifiers, etc.
This relay contact should be used only with 24 volt signals
and not line voltage power. The relay has both normally
open and normally closed contacts and can operate with
either the blower or the compressor. Use DIP switch SW2-4
and 5 to cycle the relay with blower, compressor, or control
a slow opening water valve. The relay contacts are available
on terminals #2 and #3 of P2.
A second configurable accessory relay is provided on the
AXB board. When powering high VA draw components
such as electronic air cleaners or VM type open loop water
valves, R should be taken ‘pre-fuse’ from the ‘R’ quick
connect on the ABC board and not the ‘post-fuse’ ‘R’
terminal on the thermostat connection. If not, blown ABC
fuses might result.
220 Volt Operation
All 220-240 units are factory wired for 240 volt operation.
For 220 volt operation, the red and blue transformer wires
must be switched on terminal strip PS.
L1
L2
PB1
CB
L1
L2
Compressor
Drive
Overload
CAUTION: Frequent cycling of power to the drive
can damage the drive! Wait at least 5 minutes
between cycles (connecting and disconnecting
power to the drive).