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.

ELECTRICAL WIRING DIAGRAMS FOR THE HW-120M, 160M, 200M AND 225M WATER HEATERS

I.I.D. SYSTEM (NATURAL)

FIGURE 11

15

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A.O. Smith 160M, 225M, 200M, HW-120M warranty Electrical Information
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HW-120M, 225M, 200M, 160M specifications

A.O. Smith is renowned for its range of advanced water heaters, and the 160M, 200M, 225M, and HW-120M models stand out as some of the most reliable and innovative options available. These water heaters are designed to deliver exceptional performance, energy efficiency, and user-friendly features, making them ideal for various residential and commercial applications.

The A.O. Smith 160M model boasts a robust design that ensures longevity and efficiency. It has a 160-gallon capacity, providing ample hot water for households with high demand. This model incorporates insulation technology that minimizes heat loss, contributing to energy savings and reduced utility bills. Additionally, it features a durable exterior that is resistant to rust and corrosion.

The 200M model takes performance a step further with a higher capacity of 200 gallons, making it suitable for larger homes or businesses. This model is equipped with advanced components, including a high-efficiency burner and a powerful thermocouple that ensures reliable heating. The 200M also includes user-friendly controls that allow for precise temperature settings and easy operation.

Next in line is the A.O. Smith 225M, which offers an impressive 225-gallon capacity. This model is designed for heavy-duty usage and features a reinforced tank to withstand high pressure. The 225M is also equipped with state-of-the-art flame retention technology that optimizes fuel use, enhancing the overall efficiency of the unit. This ensures that customers not only get hot water when needed but also experience considerable savings on energy costs.

Finally, the HW-120M model is a compact solution that does not compromise on performance. With a capacity of 120 gallons, it is ideal for smaller households or spaces where water heating needs are moderate. The HW-120M includes features such as an LED display for easy temperature monitoring and an integrated safety system that prevents overheating.

All these models utilize advanced technologies such as electronic ignition and enhanced insulation materials, contributing to a reduction in energy consumption and maintenance needs. The combination of these features makes A.O. Smith appliances a smart choice for consumers looking for efficiency, reliability, and performance. With a strong commitment to craftsmanship and innovation, A.O. Smith continues to set the standard in water heater technology, ensuring customers enjoy reliable hot water access while promoting energy efficiency.
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