WIRING DIAGRAM 480V THREE-PHASE (WYE)

SYSTEM CLEANING

The hot water system should be internally cleaned and flushed to remove contaminants which may have accumulated during installation. System cleaning provides chemical stability necessary for component life and system performance.

Failure to clean the system may cause:

1.Poor heating due to formation of gas.

•Residual pipe dope, thread cutting oil, solder flux, dirt and other foreign materials breakdown to form gas. This is indicated by a continuing need for purging even through the system is “closed”.

2.Pump seal leakage.

•Acidic water (low pH) and contamination such as soil and sand result in premature or recurring pump seal failures.

3.Automatic air valve leakage.

•Contaminants cause sticky sealing surfaces and result in leakage.

4.Relief valve operation.

•Gas formation increases system pressure and relief valve spillage.

5.Water leaks at joints and fittings.

•Corrosion and eventual failure of connections occur when system pH is low.

6.Noisy operation.

•Heat transfer surfaces can be fouled with dirty, oily water. This plus gas lead to noisy water circulation.

WARNING

Be sure to turn off power when working on or near the electrical system of the boiler. Never touch electrical components with wet hands or when standing in water. When replacing fuses always use the correct size for the circuit.

OPERATION

GENERAL

Never operate the heating elements without being certain the boiler is filled with water and a pressure relief valve is installed in the relief valve opening provided.

An electronic type low water cutoff is provided on all boilers as standard equipment. The water probe is installed near the top of the tank to monitor the presence of water. The control circuit is opened if the water level is below this point.

The pilot switch on the cabinet front permits the boiler to be turned on and off without having to operate the electrical disconnect switch. Additional switches may be provided for manually operating contactor coils.

WARNING

Full power is present whenever the cabinet door is opened even with the pilot switch(es) turned off. Never operate the boiler with cabinet doors open or panels removed.

FILLING

Refer to SYSTEM CLEANING section for preparing the system prior to final filling and operation.

Hard Water: in areas which have hard water it may be desirable to fill the system with soft water and/or provide water treatment as recommended by a consultant familiar with local conditions. In this way harmful water scale build-up on the heating elements is minimized.

1.Close the boiler drain valve and system valves as necessary.

2.Open a vent in the highest point of the system to allow the air to escape.

3.Fully open the make-up water inlet valve. Fill the boiler and piping.

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A.O. Smith NW 37-670 warranty Operation, System Cleaning, Filling, Failure to clean the system may cause
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NW 37-670 specifications

A.O. Smith NW 37-670 is a highly regarded water heater that stands out in the residential water heating market. Renowned for its efficiency and reliability, this unit offers homeowners a perfect blend of advanced technology, high performance, and convenience.

One of the main features of the A.O. Smith NW 37-670 is its high recovery rate, which allows for rapid heating of water to meet the demands of a busy household. With a 37-gallon tank capacity, this model can effectively supply hot water for various applications, such as showers, dishwashing, and laundry. The design incorporates a powerful heating element that ensures the water is heated quickly, thus minimizing wait times and improving overall comfort.

Efficiency is a cornerstone of the NW 37-670's design. This water heater features an impressive Energy Factor (EF), which translates to lower energy bills for homeowners. A.O. Smith has integrated advanced insulation materials to maintain water temperature longer, reducing the energy required for reheating. This not only helps in cutting down costs but also promotes eco-friendliness, making it an excellent option for environmentally conscious consumers.

The technology behind the A.O. Smith NW 37-670 includes a state-of-the-art electronic control system. This system continuously monitors the unit's performance and adjusts operations to optimize efficiency. Additionally, the water heater is equipped with a robust diagnostic system that provides real-time feedback, making it easier for homeowners to identify any potential issues before they escalate.

Durability is another defining characteristic of the NW 37-670. Constructed with high-quality materials, including a glass-lined tank for added protection against corrosion, this water heater is designed to last for years with minimal maintenance. The anode rod further enhances its longevity by reducing the potential for rust and increases the lifespan of the unit.

Installation and maintenance are straightforward due to the user-friendly design of the A.O. Smith NW 37-670. It can fit into various spaces, making it a versatile option for both new constructions and replacement projects. A.O. Smith also provides comprehensive support and warranty services, ensuring customer satisfaction and peace of mind.

In summary, the A.O. Smith NW 37-670 is a top-tier water heater that combines efficiency, advanced technology, and durable construction. With its substantial capacity, rapid recovery rate, and modern control features, it is an excellent choice for any home looking for dependable hot water solutions.
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