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Multiple Unit Control Panel for Mark IV
Up to 3 Units (Part No. 056794201)
The multiple unit control board is an accessory used when you
need to control up to 3-units from a single thermostat. The
board is typically mounted in the unit control box closest to the
thermostat. A maximum of 2 boards may be used together if up
to 6-units must be connected and controlled from a single
thermostat.
The 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
O W2 G W1 Y1
F
E
L
U
A
P
V
R
C
WSHP Mark IV/AC Board Low Voltage Terminal Strip
O W2 G W1 Y1
F
E
L
U
A
P
V
R
C
O W2 G W1 Y1
F
E
L
U
A
P
V
R
C
R
Y
G
W
R
Y
G
W
R
Y
G
W
G
W
Y
R C
WSHP Mark IV/AC Board Low Voltage Terminal Strip
WSHP Mark IV/AC Board Low Voltage Terminal Strip
Multiple Unit
Control Panel
TB3
TB2
TB1
TB4
RC
W
1
Y1
W2
Y2
G
Thermostat T
e
rminals
This version of the board uses VAC relays and should not be
used in combination with any other accessories or equipment
that require VDC connections to the "G", "W1", or "Y1" terminals
(i.e. Boilerless System Kit).
The multiple unit control board provides the components nec-
essary to protect the Mark IV/AC board from electrical damage
that may occur when using standard off-the-shelf relays.
Up to 2 Units (Part No. 106059801)
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 nec-
essary 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 W2 G W1 Y1
F
E
L
U
A
P
V
R
C
R
Y
G
W
L
Multiple Unit
Control
Panel
WSHP Mark IV/AC Board Low Voltage Terminal Strip
O W2 G W1 Y1
F
E
L
U
A
P
V
R
C
G
W
Y
C
L
RC
W
1
Y1
W2
Y2
G
Thermostat T
erminals