15
ELECTRICAL WIRING DIAGRAMS FOR THE HW-120M, 160M, 200M AND 225M WATER HEATERS
I.I.D. SYSTEM (NATURAL)
FIGURE 11
A minimum gas supply pressure of 4.5" W.C. (1.12kPa) for natural
gas and 11" W.C. (1.74kPa) for propane gas is required for
purposes of input adjustment.
ELECTRICAL INFORMATION
ALL ELECTRICAL WORK MUST BE INSTALLED IN
ACCORDANCE WITH THE NATIONAL ELECTRICAL CODE IN
THE UNITED STATES AND IN CANADA MUST CONFORM TO
LOCAL REGULATIONS OR THE CANADIAN ELECTRICAL
CODE CSA C22.
The electrical connections must be made so that both the circulator
and intermittent ignition device operate simultaneously when the
storage tank temperature control calls for heat.
The appliance, when installed, must be electrically grounded in
accordance with local codes or, in the absence of local codes, in
the United States with the NATIONAL ELECTRICAL CODE, ANSI/
NFPA 70. In Canada with the CANADIAN ELECTRIC CODE,
CSA C22.
A screw is provided in the heater junction box for a ground
connection.
All piping diagrams include an electrical wiring diagram to assist
the installer in properly wiring of the additional components
required to assure correct system operation.
Figures 11 and 12 show the heater mounted controls as they are
wired when the heater leaves the factory. Using the individual
wiring diagrams on the installation diagrams, the installer connects
his wiring to terminals in the heater(s) mounted junction box as
shown.
All wiring should be done such that the heater(s) will operate in
the following manner:
1. When the tank temperature control calls for heat:
• The circulating pump starts to operate. Once the safety flow
switch contacts close, intermittent ignition device is powered
and sequence through steps as described for I.I.D. Control
Module on Page 5.
2. When the tank temperature control is satisfied:
• The main burners should stop firing, but the circulating pump
should continue to operate for about 2 minutes when equipped
with a thermal balancer.
3. When the automatic gas shutoff control or coil protector switch
operate (break electric circuit):
• The main burners should stop firing. Circulating pump should
continue to operate.