User Guide

Field wiring (see wiring diagram, Figure 15, page 34 )
Figure 14 Field wiring overview (see Figure 15, page 34 and
Figure 16, page 35 for detailed schematic and ladder
wiring diagrams)
Line
Voltage
Multiple
boiler
communication
wiring
Low
Voltage
®
CONDENSING GAS BOILER — 70/110/155 Advanced Manual
Part number 550-100-193/0817
– 26 –
Evergreen
®
boiler wiring
Connecting terminals
All fi eld wiring is made through the eight (8) colored connectors
(shipped loose with boiler) directly to the control module. Line volt-
age, 120 VAC, terminals are on the top of the control module. Low
voltage, 24 VAC, terminals are on the bottom of the control module.
Wire entrances
Wire entrance knockouts are provided on the top left, the bottom
left side and the top right side of the boiler cabinet:
1. Line voltage— fi ve (5) knockouts on the top left of the cabinet
(Line In, Output 1, 2, 3, Boiler Circ.).
2. Low voltage— two (2) knockouts on the bottom left side of
the cabinet.
3. Multiple boiler communication wiring—a single knockout on
the top right side of the cabinet.
Installer MUST use a strain relief through jacket
knockouts. Failure to do so can cause severe personal
injury, death or substantial property damage.
Installer MUST SEAL all electrical entrances using a
sealed strain relief or a strain relief sealed with duct
seal putty or silicone. Sealing the entrances prevents
the boiler from drawing air from inside the boiler
room. This is particularly important if the boiler is
located in the same room as other gas appliances.
Failure to seal entrances could result in sever per-
sonal injury, death or substantial property damage.
Wire routing in the cabinet
Line voltage: (120VAC in, circulator outputs)
1. Install four (4) of the wire tie bases to the holes on the left side
interior of the cabinet.
2. Line voltage should be wired from the top left electrical en-
trances following the left side of the cabinet.
3. Wires should be bundled together and secure with the
provided wire ties to the wire tie bases located on the left
side wire chase. Two (2) sets of bases are provided, one (1)
for line in and one (1) for the circulator outputs. Route
wires in front of the transformer then into terminal blocks.
4. Strip end of wire no more than 1/8” to avoid exposing unin-
sulated wire.
5. It is recommended to install an On/Off service switch in a
junction box mounted near the boiler. Installation must meet
all National and local electrical codes.
Low voltage:
1. Mount low voltage wire grommet to desired low voltage
knockout.
2. Thermostat, aquastat, limit devices, system sensors, 0-10VDC
input and outdoor temperature sensor wire pairs should be
routed through the grommet.
3. Wires should be connected directly into the corresponding
terminal block.
4. Low water cutoff (optional) should be routed following the
instructions in step 3. Provide strain relief and a seal at cabinet
entry.
5. Bundle all wires together with provided wire ties.
6. After wires are attached to the control terminal blocks, make
sure wires are properly sealed in the cabinet electrical entrances.
Multiple boiler communication wiring
1. Wires should be shielded thermostat wires, or equivalent.
2. Route wires through top right knockout to communication
board on display bracket.
3. Provide strain relief and seal at cabinet entry.
Wiring to
Comm board
inside cabinet
boiler