User Guide

Part number 550-100-193/0817
– 33 –
®
CONDENSING GAS BOILER — 70/110/155 Advanced Manual
M. Proof of closure (flow switch and/or CAD) – OPTIONAL
Jumper on Terminal Strip P7 (EVG control)
1. A flow switch or combustion air damper (CAD) interlock can be con-
figured by clipping the jumper on terminal strip P7. Strip the jumper
ends and wire components as shown at right and in the wiring diagram
(Figure 15, page 34).
2. No control settings are required when using a flow switch.
a. Each boiler is assumed to have its own flow switch, wired as shown
at right.
3. To configure the EVG control for a CAD interlock:
a. Assign any INPUT (recommend
INPUT 3) as a AUX PUMP/ OUT-
PUT
function. For multiple boiler applications, use any input on
any boiler in the network
. The example at right demonstrates using
INPUT/OUTPUT 3 on the MASTER boiler.
b. For the AUX PUMP/ OUTPUT operating mode, select ANY BURNER
DEMAND. This ensures the damper will be activated any time any
boiler is called on to fire.
c. Wire the corresponding
OUTPUT (following recommendation,
OUTPUT 3) to provide 120 VAC to the damper motor when activated.
Use an isolation relay if damper motor requires another voltage or
more than 2.0 amps on 120 VAC.
d. For a multiple boiler system, when any boiler is called on to fire,
whether for local or network demand, the combustion air damper will
be powered (120 VAC) from the assigned boiler
OUTPUT as shown
at right (using OUTPUT 3 on the master boiler).
The devices used must provide electrically isolated contacts,
because the P7 jumper circuit carries 5 VDC.
Ensure that the wires are connected only as shown. The right
side of each jumper must connect only to the right side of
other jumpers
. Failure to comply will cause incorrect opera-
tion of the proof of closure circuits.
See Figure 15, page 34 for details
N. Multiple Boiler and BMS Connections
Terminal Strip JP4 on Comm Board (display bracket right side)
1. The boiler control is capable of multiple boiler communication and
control of up to eight Evergreen
®
boilers in one installation.
2. The boiler control is also capable of BMS (Building Management System)
communication.
3. See wiring at right and in the wiring diagram (Figure 15, page 34).
4. Use shielded 3-wire cable. Do not exceed 1,000 feet wire length.
5. Boiler to Boiler wiring connections
a. Connect 3-wire cable between Boiler-to-Boiler OUT (JP4-GND, B2,
A2) on one boiler to Boiler-to-Boiler IN (JP4-GND, B3, A3) on the
next boiler.
b. Continue this wiring until all boilers are interconnected.
6. MODBUS to BMS (Building Management System)
a. The control is equipped with MODBUS communication to com-
municate with a BMS.
b. Use terminal JP4 (JP4-BMSA, BMSB, GND) to wire to the BMS
control.
c. If the BMS uses BACnet protocol, install a BACnet converter between
the BMS and the Evergreen
®
MODBUS-to-BMS terminals (P5).
See Figure 15, page 34 for details
Field wiring (see wiring diagram, Figure 15, page 34)(continued)