Start-up Instructions

VB/VW 500/750/1000

Series 100/101

Before starting the boiler, please review the boilers instruction manual (AOS Part Number 212800) supplied with the boiler. This is a powered combustion copper tube boiler. Please contact an authorized A.O. Smith representative before starting the unit. Ensure that the water piping, gas line, controls, and venting have been installed per the instruction manual.

Gas supply lines should be sized in accordance with the current edition of National Fuel Gas Code (ANSI Z223.1/NFPA 54) or CAN/CSA B149.1 The Canadian Natural Gas and Propane Installation Code.

Make sure the boiler is not damaged. If the unit is damaged, contact an A.O. Smith representative for service or replacement parts prior to starting the boiler.

This boiler is equipped with a Modulating EMC 5000 control system. The EMC 5000 displays the system status and errors that may occur during normal operation. For full details on the controls, please refer to the Installation Manual supplied with the boiler. The boiler must be installed according to the instructions provided with the unit. Failure to do so will void the warranty.

The following test equipment should be on hand: (all test equipment must be acclimated to ambient temperature before calibration and use.)

•A combustion analyzer capable of measuring CO and CO2 or O2.

•A digital manometer or pressure gauges capable of accurately displaying 0 – 15 (± .01) inches of water column.

•Combination volt/ammeter

•TORX® T40 or 5mm hex wrench – for setting gas mixture at gas valve

•3mm or 7/64 in hex wrench – for setting gas mixture at gas valve

I. Verify utilities

•Ensure that the water piping, gas line, controls, and venting have been installed per the instruction manual.

•Be certain that the system is full of water, that air is purged from all lines, the boiler, and storage tank.

•Ensure that no leaks are present and that all supply and return water valves are open.

•Upstream gas valve should remain closed until start up.

II. Component Sequence Verification

•Ensure that the power supply meets these requirements: single phase, Minimum: 108 VAC RMS; Maximum: 132 VAC RMS and is on a dedicated circuit breaker with separate neutrals and grounds.

•Ensure all control wiring is run in a dedicated conduit per instruction manual.

•Perform power supply test outlined in the instruction manual.

•Ensure that the upstream manual gas valve of the boiler is open.

Prior to turning on the gas, proper sequence of most of the system can be verified. With the water turned on, and the gas turned off by the downstream manual valve, start the system and allow it to run through a heating cycle. It should stop when it checks for the flame and declare a fault. This will verify that the pump, flow switch, igniter, variable frequency drive, modulating gas valve, blower and low/ high blower prover switches are all functioning properly.

III. Initial Boiler Set-up Verification

•Drill a maximum 7/16” hole in the side of the vent boot tee approximately 8” from back panel to insert the gas analyzer probe.

The hole must be sealed upon completion of the start-up testing.

•Open the downstream manual gas valve to the boiler and purge air from the line.

PRINTED 0608

212936-002

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A.O. Smith VB/VW 500/750/1000 instruction manual Verify utilities, II. Component Sequence Verification
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VB/VW 500/750/1000 specifications

A.O. Smith is a well-known name in the water heating industry, and its VB/VW series models, particularly the 500, 750, and 1000, are designed for commercial applications, offering a range of advanced features and technologies. These models are recognized for their high efficiency, reliability, and performance, making them suitable for various industries, including hospitality, healthcare, and food service.

One of the standout features of the VB/VW series is their impressive recovery rates. With a powerful heating capacity, these units can deliver hot water consistently, ensuring that large demands are met without interruptions. This is particularly important for businesses that rely on a steady supply of hot water throughout the day.

The VB/VW series utilizes advanced insulation technology, which significantly reduces energy loss. This feature not only improves the overall energy efficiency of the units but also contributes to lower operational costs. The use of foam insulation helps maintain water temperature, allowing for reduced energy consumption and enhanced performance.

These models come equipped with advanced control systems, providing users with greater flexibility and ease of operation. The user-friendly digital display allows for precise temperature control and monitoring, ensuring optimal performance is maintained at all times. Additionally, the temperature settings can be adjusted to suit specific water heating requirements, catering to the unique needs of various applications.

A.O. Smith's commitment to safety is evident in the design of the VB/VW series. These models incorporate multiple safety features, including a high-temperature limit switch, fusible links, and proper venting systems, ensuring safe operation in any environment. The robust construction of the units, combined with the use of high-quality materials, enhances durability and extends the lifespan of the water heaters.

Moreover, these models are designed for easy maintenance. The intuitive design allows for simplified access to key components, making routine checks and servicing straightforward for technicians. This ease of maintenance contributes to reduced downtime and enhances the overall operational efficiency of the water heating system.

In summary, the A.O. Smith VB/VW 500, 750, and 1000 water heaters are engineered to meet the demands of commercial applications with their high efficiency, advanced technology, and safety features. With their ability to deliver consistent hot water, coupled with ease of maintenance and reduced energy consumption, these models stand out as a reliable choice for businesses seeking efficient and effective water heating solutions.
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