IM 742 / Page 19
Multiple Unit Control (up to 2 units) (P/N 106059801)
This multiple unit control board is an accessory used when
you need to control up to 2-units from a single thermostat .
The board is typically mounted in the unit control box closest
to the thermostat . The “G”, “W”, “Y”, “C”, and “L” connections
are short flying leads pre-attached to the board . A maximum
of 3 boards may be used together if up to 4-units must be
connected and controlled from a single thermostat .
This version of the board uses VDC relays and should
not be used in combination with any other accessories
or equipment that require VAC connections to the “G”, “W1”,
or “Y1” terminals (i .e . Boilerless System Kit) . Do not use
the unoccupied (U-terminal) feature with the multiple unit
control board .
The multiple unit control board provides the components
necessary to protect the Mark IV/AC board from electrical
damage that may occur when using standard off-the-shelf
relays .
WSHP Mark IV/AC Board Low Voltage Terminal Strip
O W 2 G W1 Y1 F
E L
U A P V
R C
R
Y
G
W
L
G W1 Y1 R Rc C
Thermostat Terminals
Multiple Unit
Control Panel
O W 2 G W1 Y1 F
E L
U A P V
R C
G W Y
C L
WSHP Mark IV/AC Board Low Voltage Terminal Strip
WSHP Mark IV/AC Board Low Voltage Terminal Strip
O W2 G W1 Y1 F E L U A P V R C
1
2
3
Auxiliary Relay
Orange
Yellow
White
6 3 1
Ti
me Clock
(by others)
Daisy-chain to
additional Mark IV/AC
board “U” terminals
B
L
GN
Motorized Valve & Relay for Unit Sizes 007 thru 070
Wired as shown below the motorized valve will open on a
call for compressor operation . Valves for unit sizes 007 to
019 are
1
⁄
2
" power-open spring-return while unit sizes 024
to 070 are
3
⁄
4
" power-open spring return . Other thermostat
combinations may be used . Valve and auxiliary relay are
purchased separately .
Note: The wiring shown below can only be used when the “P”
terminal is not being used as a pump restart signal to other equip-
ment . If the “P” terminal must be used as a pump restart signal to
other equipment, then wire the auxiliary relay’s yellow wire to “Y1”,
white wire to “W1”, and orange wire to “C”, then the valve will
open on a call for occupied heating or cooling from the thermostat .
6
3
1
Black to 6
White to 1
Plug
Pins,
Female
Conduit
Anti-Short
Bushing
Connector
Valve
36" (915 mm)
Lead Length
P/N 060977401 - 1/2" Motorized Valve Kit
P/N 060977301 - 3/4" Motorized Valve Kit
P/N 859004354 - Valve Relay Kit
