17
HP IOM, Rev. B
Enertech Global
Section 5: Unit Piping Installation
+
-
DC
Bridge
LED
Diode
RY1
24VAC input
from unit #1
+
-
Diode
RY2
24VAC input
from unit #2
RY1
RY2
240VAC input
240VAC to pump(s)
24VAC 24VAC
Figure 1: Board Layout
Figure 2: Board Schematic
240V IN 240V OUT
Relay
Relay
240VAC
Power Source
240VAC
to Pump(s)
24VAC
connection
to unit #2
(Y1 & C From Thermostat)
24VAC
connection
to unit #1
(Y1 & C From Thermostat)
APSMA PUMP SHARING MODULE
The pump sharing module, part number APSMA, is designed
to allow two units to share one flow center. With the APSMA
module, either unit can energize the pump(s). Connect the
units and flow center as shown in the drawing, below. A
schematic of the board is also shown. The module must be
mounted in a NEMA enclosure or inside the unit control
box. Local code supersedes any recommendations in this
document�
APSMA Module Layout
APSMA Module Wiring Schematic
