Lochinvar SNR150-100, SNA500-125, SNR200-100, SNA285-125 Gas pressure, Gas valve replacement

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TM

Installation & Service Manual

7Gas connections

17.Check burner performance by cycling the system while you observe burner response. The burner should ignite promptly. Flame pattern should be stable. Turn system off and allow burner to cool, then cycle burner again to ensure proper ignition and flame characteristics.

Figure 7-4Inlet Gas Supply Check - Models SNR150/100 -- SNA285-125

LOOSEN THE SET SCREW ONE (1) FULL TURN AND PLACE THE MANOMETER TUBING OVER THE PRESSURE TAP

Gas pressure

The gas pressure must remain between 4 inches w.c. (natural), 8 inches w.c. (LP) minimum and 14 inches w.c. (natural and LP) maximum during stand-by (static) mode and while in operating (dynamic) mode. If an in-line regulator is used, it must be a minimum of 10 feet from the Shield water heater. It is very important that the gas line is properly purged by the gas supplier or utility company. Failure to properly purge the lines or improper line sizing, will result in ignition failure.

The problem is especially noticeable in NEW LP installations and also in empty tank situations. This can also occur when a utility company shuts off service to an area to provide maintenance to their lines.

Gas valve replacement

The gas valve MUST NOT be replaced with a conventional gas valve under any circumstances. As an additional safety feature, this gas valve has a flanged connection to the venturi and blower.

DETAIL

Figure 7-5Inlet Gas Supply Check - Model SNA400/125

LOOSEN THE SET SCREW ONE (1) FULL TURN AND

PLACE THE MANOMETER TUBING OVER THE

PRESSURE TAP

￿WARNING

￿WARNING

Failure to follow all precautions could result in fire, explosion, or death!

DO NOT adjust or attempt to measure gas valve outlet pressure. The gas valve is factory-set for the correct outlet pressure. This setting is suitable for natural gas and propane (when configured for LP), requiring no field adjustment. Attempting to alter or measure the gas valve outlet pressure could result in damage to the valve, causing potential severe personal injury, death, or substantial property damage.

DETAIL

Figure 7-6Inlet Gas Supply Check - Model SNA500/125

LOOSEN THE SET SCREW ONE (1) FULL TURN AND PLACE THE MANOMETER TUBING OVER THE PRESSURE TAP

DETAIL

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Contents Installation & Service Manual What to do if YOU Smell GASContents Please read before proceeding Hazard definitionsShield How it works BlowerModels SNR150-100 -- SNA285-125 Model SNA400-125 Model SNA500-125Ratings CSADetermine water heater location Installation must comply withCloset and alcove installations Before locating the water heater, check1Closet Installation Minimum Required Clearances Prevent combustion air contamination Flooring and foundationRemove water heater from wood pallet Do not install the Shield water heater into 3Combustion Air Direct from Outside Minimum Recommended Combustion AIR Supply to Equipment Room General venting Direct venting optionsVent pipe and fittings Venting and combustion airCanada Air intake/vent connections Air inlet pipe materialsVent and air piping Vent LengthRemoving from existing vent Vent/air termination sidewall If using the alternate sidewall terminationSidewall direct venting Vent Size2Clearance to Gravity Air Inlets Termination and fittings Prepare wall penetrationsPrepare wall penetrations Alternate Field Supplied Option Multiple vent/air terminations 5AMultiple Vent Terminations must also comply with -1ADescription and usage Sidewall termination installationSidewall termination optional concentric vent 9Concentric Vent Dimensional Drawing 12Concentric Vent Sidewall Attachment Multiventing sidewall terminationsVertical direct venting Vent/air termination verticalPrepare roof penetrations 2Vertical Terminations with Multiple Water HeatersVertical termination installation Vertical termination optional concentric vent6Concentric Vent Roof Installation Multiventing vertical terminationsConventional and sidewall venting 1Vertical Direct Venting w/Room AirScalding System pipingSystem water piping methods General piping informationDelta T Piping componentsWater chemistry Single Unit 3Multiple Units Water Tank Supply Connecting gas supply piping Gas connectionsNatural gas Propane gasLength of Pipe in Straight Feet for 1/2 PSI Natural Gas Pipe Capacity ChartCheck inlet gas supply Gas valve replacement Gas pressureField wiring 3Low Voltage Field Wiring Connections Inputs Condensate disposal Condensate drainFinal checks before starting the water heater Start-upCheck for gas leaks Inspect/fill condensate system Check system and water heater Start the water heaterIf water heater does not start correctly Check flame and combustion2Operating Instructions Models SNR150-100 -- SNA285-125 3Operating Instructions Models SNA400-125 -- SNA500-125 Operating information Temperature controlProtection features GeneralSaving parameters Water heater temperature regulationAdjustable control parameters Sequence of operation HTR IgnitionShield control module 1Control PanelStatus display screens Status Display ScreensStatus Display Screens cont’d Owner maintenance Maintenance Maintenance and annual startupService technician Maintenance Check expansion tank Flue vent system and air pipingCheck water system Check water heater relief valveCheck control settings Check ignition ground wiring Check burner flameCheck all water heater wiring Check flame signalOiled bearing circulators Cleaning heat exchangerHandling ceramic fiber materials Niosh stated First AidCheck control module fuses TroubleshootingBefore troubleshooting Check the followingUnit Does Not Modulate No DisplayNo Burner Operation Above 50%Checking temperature sensors Temperature F Resistance ΩTroubleshooting No Flame Ign FlameSequence GV/Relay No FlameRunning FailFan Low Manual ResetHigh Limit Fan Speed LowFan Speed High SwitchFan High Sensor OpenParameters ProgrLow 24 VAC Service BlkWatch Dog Error Write EEPromOr Obstruction Combustion Analysis ProcedureGas Valve Adjustment Gas Supply PressureModel SNA400-125 Gas valve adjustment procedureModels SNR150-100 -- SNA285-125 Model SNA500-125Diagrams 120 VACLOW Voltage

SNA400-125, SNR150-100, SNA285-125, SNR200-100, SNA500-125 specifications

Lochinvar has established itself as a leader in the realm of high-efficiency heating solutions, and its line of condensing boilers, including the SNA500-125, SNR200-100, SNA400-125, SNA285-125, and SNR150-100, exemplifies the brand’s commitment to innovation, efficiency, and reliability.

The SNA500-125 model stands out with its impressive heating capacity, designed for larger commercial applications. Featuring advanced modulating burners, it can precisely adjust its output based on real-time demand, significantly enhancing energy efficiency. The stainless steel heat exchanger ensures robust durability and improved thermal performance, while the integrated controls offer advanced diagnostic capabilities and user-friendly operation.

Next in the lineup, the SNR200-100 serves as a versatile option for mid-sized applications. Its compact design allows for flexible installation, making it a valuable choice for facilities with limited space. The boiler incorporates a high-efficiency combustion system that maximizes fuel utilization, while its low NOx emissions technology aligns with environmental standards, reducing the carbon footprint of users.

The SNA400-125 delivers a robust solution for diverse heating needs, equipped with state-of-the-art modulation technology that not only optimizes efficiency but also offers quiet operation – a crucial feature for facilities where noise reduction is paramount. This model also includes built-in redundancy options, enhancing reliability during peak operational periods.

The SNA285-125 provides a balance of performance and efficiency for smaller commercial settings. Its innovative control system offers precise temperature management and easy integration with existing systems. Energy Star certified, this model is not only cost-effective but supports sustainability efforts in various industries.

Lastly, the SNR150-100 is ideally suited for light commercial applications, featuring a compact footprint and excellent heat transfer capabilities. The user-friendly interface and robust safety features make it an excellent choice for operators prioritizing both ease of use and reliability.

All these models incorporate Lochinvar's commitment to superior design and advanced technologies, setting a benchmark in the high-efficiency heating market. With a focus on long-term performance and compliance with modern environmental standards, Lochinvar continues to deliver top-tier solutions tailored to meet diverse customer needs. Whether for large-scale operations or smaller settings, these boilers represent a significant advancement in commercial heating technology.
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