Lochinvar SNA400-125, SNA500-125 Manual Reset, High Limit, Fan Low, Fan Speed Low, Open

Page 64

TM

Installation & Service Manual

13 Troubleshooting

Table 13E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface

FAULT

DESCRIPTION

CORRECTIVE ACTION

 

 

 

 

The outlet water temperature has exceeded

• Verify that the system is full of water and that all air

 

the fixed setting of the manual reset high

has been properly purged from the system.

 

limit.

• Verify that the water heater is piped properly into the

 

 

 

 

heating system. Refer to Section 6 - System Piping

Manual Reset

 

for the proper piping methods for the Shield water

 

heater.

 

 

High Limit

 

• Check 120 VAC to water heater pump motor on a call

(will require a manual

 

 

for heat. If voltage is not present, check wiring back

reset once the condition

 

 

to the main control board.

has been corrected. Press

 

 

 

 

 

the RESET button on the

 

• Replace the main control board if necessary.

display to reset.)

 

• If 120 VAC is present on a call for heat and the water

 

 

 

 

heater pump is not operating, replace the pump.

 

 

• Check resistance of water sensors and compare to

 

 

Table 13B on page 60 of this manual. Replace

 

 

sensor if necessary.

 

 

 

 

 

The actual fan RPM is 30% lower than what

• Vent/air intake lengths exceed the maximum allowed

 

is being called for.

lengths.

Refer to Section 2 - General Venting for

 

proper lengths.

 

Fan Low

 

 

 

• Check for obstruction

or blockage in the vent/air

OR

 

 

intake pipes or at terminations.

Fan Speed Low

 

 

 

 

 

(will require a manual

 

• Check the wiring connections at the fan and at the

reset once the condition

 

main control board.

 

has been corrected. Press

 

• Replace the fan.

 

the RESET button on the

 

 

 

 

 

 

display to reset.)

 

• Replace the main control board.

 

 

 

 

Blown fuse.

• Replace fuse F4 on the control board, see page 58

 

of this manual.

 

 

 

 

 

 

 

 

 

• Check the wiring connections to switch. Wires

 

 

should be connected to the common and normally

 

 

closed terminals.

 

 

 

• Air intake lengths exceed the maximum allowed

 

 

lengths. Refer to Section 2 - General Venting for

APS

 

proper lengths.

 

 

• Check

for obstruction or blockage in the air

Open

 

 

intake pipes or at terminations.

(will require a manual

 

 

 

 

 

reset once the condition

Air pressure switch contacts are open.

• Check reference hoses connected to the air pressure

has been corrected. Press

 

switch for blockage or obstruction.

the RESET button on the

 

• Inspect

the burner.

Reference page 56 of this

display to reset.)

 

 

manual for removal and cleaning procedures.

 

 

 

 

Replace if necessary.

 

 

 

• Inspect the heat exchanger. Reference page 57 of

 

 

this manual for removal and cleaning procedures.

 

 

Replace if necessary.

 

 

 

• Faulty air pressure switch. Replace switch.

 

 

 

 

 

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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 CSAInstallation must comply with Closet and alcove installationsDetermine water heater location Before locating the water heater, check1Closet Installation Minimum Required Clearances Remove water heater from wood pallet Flooring and foundationPrevent combustion air contamination 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 optionsCanada Venting and combustion airVent pipe and fittings Air intake/vent connections Air inlet pipe materialsRemoving from existing vent Vent LengthVent and air piping If using the alternate sidewall termination Sidewall direct ventingVent/air termination sidewall Vent Size2Clearance to Gravity Air Inlets Prepare wall penetrations Alternate Field Supplied Option Prepare wall penetrationsTermination and fittings Multiple vent/air terminations 5AMultiple Vent Terminations must also comply with -1ASidewall termination optional concentric vent Sidewall termination installationDescription and usage 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 AirSystem piping System water piping methodsScalding General piping informationWater chemistry Piping componentsDelta T Single Unit 3Multiple Units Water Tank Supply Connecting gas supply piping Gas connectionsNatural gas Propane gasCheck inlet gas supply Natural Gas Pipe Capacity ChartLength of Pipe in Straight Feet for 1/2 PSI Gas valve replacement Gas pressureField wiring 3Low Voltage Field Wiring Connections Inputs Condensate disposal Condensate drainCheck for gas leaks Inspect/fill condensate system Start-upFinal checks before starting the water heater Start the water heater If water heater does not start correctlyCheck system and water heater Check flame and combustion2Operating Instructions Models SNR150-100 -- SNA285-125 3Operating Instructions Models SNA400-125 -- SNA500-125 Temperature control Protection featuresOperating information GeneralAdjustable control parameters Water heater temperature regulationSaving parameters Sequence of operation HTR IgnitionShield control module 1Control PanelStatus display screens Status Display ScreensStatus Display Screens cont’d Service technician Maintenance Maintenance and annual startupOwner maintenance Maintenance Flue vent system and air piping Check water systemCheck expansion tank Check water heater relief valveCheck ignition ground wiring Check burner flame Check all water heater wiringCheck control settings Check flame signalCleaning heat exchanger Handling ceramic fiber materialsOiled bearing circulators Niosh stated First AidTroubleshooting Before troubleshootingCheck control module fuses Check the followingNo Display No Burner OperationUnit Does Not Modulate Above 50%Checking temperature sensors Temperature F Resistance ΩTroubleshooting Sequence FlameNo Flame Ign No Flame RunningGV/Relay FailManual Reset High LimitFan Low Fan Speed LowSwitch Fan HighFan Speed High Sensor OpenParameters ProgrService Blk Watch Dog ErrorLow 24 VAC Write EEPromCombustion Analysis Procedure Gas Valve AdjustmentOr Obstruction Gas Supply PressureGas valve adjustment procedure Models SNR150-100 -- SNA285-125Model SNA400-125 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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