Lochinvar 151 - 801 service manual Checking temperature sensors, Temperature F Resistance Ω

Page 26

Service Manual

3Troubleshooting

Checking temperature sensors

The water heater temperature sensors (inlet water, outlet water, system water, and flue) are all resistance type devices. The following tables show the correct values for the sensors at various temperatures. Use an ohmmeter to read the resistance of the sensor at a known temperature. If the resistance of the sensor does not closely match its corresponding table, replace the sensor.

It is important to note that the flue and outlet water sensors have two temperature sensing devices in one housing. These devices are designated as S1a/S1b, outlet sensor and S3a/S3b, flue sensor. Please reference the wiring diagram in the Armor Water Heater Installation and Operation Manual for correct terminal location.

Table 3B - Inlet System Sensor Resistance vs. Temperature

 

Temperature °F

Resistance Ω

Temperature °F

Resistance Ω

 

 

 

 

 

 

50

18,780

158

1,990

 

 

 

 

 

 

68

12,263

176

1,458

 

86

8,194

194

1,084

 

 

 

 

 

 

104

5,592

212

817

 

122

3,893

--

--

 

140

2,760

--

--

 

 

 

 

 

 

 

 

 

 

Table 3C - Outlet Water Sensor Resistance vs. Temperature

 

 

S1a

 

 

S1b

 

 

 

(Wire Color - R/BK and Y)

 

 

(Wire Color - G and Y)

 

 

 

 

 

 

 

 

 

 

 

Temperature

Resistance

Temperature

Resistance

Temperature

Resistance

Temperature

Resistance

 

 

 

 

 

 

 

 

 

 

50

19,553

158

2,004

50

40,030

158

3,478

 

 

 

 

 

 

 

 

 

 

68

12,690

176

1,464

68

25,030

176

2,492

 

86

8,406

194

1,084

86

16,090

194

1,816

 

 

 

 

 

 

 

 

 

 

104

5,715

212

816

104

10,610

212

1,344

 

122

3,958

 

 

122

7,166

 

 

 

 

 

 

 

 

 

 

 

 

140

2,786

 

 

140

4,943

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 3D - Flue Sensor Resistance vs. Temperature

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

S3a

 

 

S3b

 

 

 

(Wire Color - W/B and Y)

 

 

(Wire Color - PR and Y)

 

 

 

 

 

 

 

 

 

 

 

Temperature

Resistance

Temperature

Resistance

Temperature

Resistance

Temperature

Resistance

 

 

 

 

 

 

 

 

 

 

50

40,030

158

3,478

50

258,500

158

16,870

 

 

 

 

 

 

 

 

 

 

68

25,030

176

2,492

68

125,500

176

12,000

 

86

16,090

194

1,816

86

80,220

194

8,674

 

 

 

 

 

 

 

 

 

 

104

10,610

212

1,344

104

52,590

212

6,369

 

122

7,166

 

 

122

35,270

 

 

 

 

 

 

 

 

 

 

 

 

140

4,943

 

 

140

24,160

 

 

 

 

 

 

 

 

 

 

 

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Contents Models 151 Contents Niosh stated First Aid Please read before proceedingHandling ceramic fiber materials Maintenance What is in this manual?Service TroubleshootingService Armor water heater displaySmart System Control Board Control inputsSmart System Control Board Control outputsHow the water heater operates Access modesGeneral Operation Sequence of operationOperation Display Display panel menu access Button Screen Operation Display StatusDisplay panel parameter access Parameter table GeneralModes Viewable and changeable control parameters Functions DHW SettingsData Logging Anti-CyclingControl modes Minimum On/Off Time Circulation pumpsService Notification 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 wiringCheck all water heater wiring Perform start-up and checksReview with owner Check flame signalCleaning heat exchanger Oiled bearing circulatorsCheck control module fuses TroubleshootingBefore troubleshooting Check the followingOperation No DisplayNo Burner Unit Does NotWire Color R/BK and Y Wire Color G and Y Checking temperature sensorsTemperature F Resistance Ω Resistance TemperatureRelief Valve NoisyNo Pump OpeningFault Description Corrective Action Flow SwitchAnti-cycling Flame Fail IgnNo Flame RunningFlame Sequence Auto ResetManual Reset High LimitGV/Relay Fan LowFan Speed Low FailFlue Temp High Sensor ShortedLouver Proving Delta T HighRem Ctrl Flt Service BlkOutlet Temp High Fatal Error Watch Dog ErrorNo Error Stored Low 24 VACOr Obstruction Combustion Analysis ProcedureGas Valve Adjustment Gas Supply PressureModel Gas valve adjustment procedureModels 151 4Gas Valve Adjustment Model Models 601

151 - 801 specifications

Lochinvar 151 - 801 is a high-efficiency commercial water heater designed to meet the demanding needs of various applications in the hospitality, healthcare, and educational sectors. This advanced system provides reliable hot water with enhanced performance while promoting energy conservation and sustainability.

One of the standout features of the Lochinvar 151 - 801 is its powerful heating capability. With a robust heating input of up to 150,000 BTU per hour, it ensures a steady supply of hot water even during peak demand times. The efficient heat exchanger design optimizes thermal performance, allowing for quicker recovery rates, which is essential for facilities requiring substantial hot water usage.

This model integrates cutting-edge technologies to maximize energy efficiency. Utilized in the Lochinvar 151 - 801 is the Smart System control technology, which provides precise temperature management and diagnostics. This feature not only enhances operation efficiency but simplifies service and maintenance by providing real-time data and alerts, leading to reduced downtime.

Additionally, the Lochinvar 151 - 801 employs a stainless-steel tank construction that promotes durability and robustness. The tank is adequately insulated to minimize heat loss, thus keeping energy costs down. Its compact design also allows for easy installation in various spaces, including those with limited footprints.

Moreover, the unit features advanced combustion technology, including a modulating gas valve that adjusts the flame size according to demand, promoting even greater efficiency. This ensures that the water heater operates at optimum performance levels, reducing fuel consumption while ensuring a consistent supply of hot water.

Safety is a primary concern for Lochinvar, and the 151 - 801 model includes several integrated safety features, such as an ignition safety shutoff and a temperature/pressure relief valve. These systems work together to provide peace of mind while ensuring the unit operates safely within its designated parameters.

In conclusion, the Lochinvar 151 - 801 is an exemplary choice for commercial applications, offering powerful performance, efficient technologies, durable construction, and enhanced safety features. With its combination of high output and advanced monitoring capabilities, it stands as a reliable solution for organizations seeking an effective hot water heating solution.