User Guide

Part number 550-100-400/0717
30
Field wiring — basic system
3EEPAGE!DVANCEDSECTIONFOROTHERWIRINGOPTIONS
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SERIES 4 GAS-FIRED WATER BOILERBoiler Manual
%,%#42)#!, 3(/#+ (!:!2$ — For your
safety, turn off electrical power supply at service
entrance panel before making any electrical connec-
tions to avoid possible electric shock hazard. Failure
to do so can cause severe personal injury or death.
The installation must comply with: National Electrical
Code and any other national, state, provincial or local
codes or regulations. In Canada, CSA C22.1 Canadian
Electrical Code Part 1, and any local codes.
Wiring must be N.E.C. Class 1. If original wiring
as supplied with boiler must be replaced, use only
type 105 °C wire or equivalent. Boiler must be
electrically grounded as required by National Elec-
trical Code ANSI/NFPA 70 – latest edition, and/
or the Canadian Electrical Code Part I, CSA C22.1,
Electrical Code.
The boiler when installed, must be electrically bonded
to ground in accordance with the requirements of the
authority having jurisdiction or, in the absence of
such requirements, with the National Electrical Code,
ANSI/NFPA 70 – latest edition, and/or the Canadian
Electrical Code Part I, CSA C22.1, Electrical Code.
Line voltage power input
1. Provide and install a fused disconnect or service switch
(15-ampere rated recommended) as required by applicable
codes.
2. Connect minimum 15-ampere, 120 VAC power wiring
to Ultra boiler line voltage terminal strip as shown in
Figure 34, page 31 , and Figure 111, page 96 .
Wiring circulators
1. The U-Control provides for connection of up to three circula-
tors, one of which must be the boiler circulator. In addition,
you can connect a system circulator and a DHW circulator,
for examples.
4HE MAXIMUM ALLOWABLE CURRENT FOR EACH
CIRCULATORISAMPSAT6!#
. For circula-
tors with higher amp ratings, you must install a
circulator relay or starter to provide line voltage to
the circulator. For circulators rated over 2.2 amps,
connect only the circulator relay or starter coil to
the Ultra circulator terminals.
Wiring — general
1. The U-Control provides plug-in, color-coded, non-
interchangeable terminal strips for all fi eld wiring. See the
schematic diagram ( Figure 111, page 96LADDERDIAGRAM
( Figure 112, page 97 ).
2. The U-Control provides programmable fl exibility in system
operation, allowing control of heat supply for up to three dif-
ferent heating systems. Read this manual thoroughly before
connecting the wiring to ensure trouble-free start-up and
operation.
Wiring — overview
See this and following pages for wiring information. Also
see the Advanced section of this manual for additional wir-
ing connections and options
.
Make the following connections, some of which depend on
your system and how the U-Control will be programmed.
#ONNECT6!#POWERMINIMUMAMPSOURCE
#ONNECTWIRINGFORUPTOTHREECIRCULATORS
#ONNECTTHERMOSTATSANDORHEATDEMANDCONTACTS
s The U-Control can regulate the boiler for up to three
different heating systems.
)NSTALLSYSTEMOUTDOORSENSORSWHENUSED
s The boiler is shipped with an outdoor sensor, a system
supply sensor and a system return sensor. The system
supply sensor will be required for most space heating ap-
plications. The system return sensor must also be installed
when using the system supply sensor. Use of the outdoor
sensor is optional.
s Locate the sensors on the system piping as shown in
Figure 4, page 11 and other piping drawings throughout
this manual.