Service Manual

3Troubleshooting

Checking temperature sensors

The boiler temperature sensors (inlet water, outlet water, system water, flue, and outdoor air) 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.

Table 3B - Inlet/Outlet System Sensor Resistance vs. Temperature

Temperature

Resistance

 

Temperature

Resistance

 

 

 

 

 

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 - Flue Temperature Sensor Resistance vs. Temperature

 

 

 

 

 

 

Temperature

Resistance

 

Temperature

Resistance

 

 

 

 

 

68

14,773

 

176

1,707

 

 

 

 

 

86

9,804

 

194

1,266

 

 

 

 

 

104

6,652

 

212

952

 

 

 

 

 

122

4,607

 

230

726

 

 

 

 

 

140

3,252

 

248

560

 

 

 

 

 

158

2,337

 

--

--

 

 

 

 

 

 

 

 

 

 

Table 3D - Outdoor Air Sensor Resistance vs. Temperature

 

 

 

 

 

 

 

Temperature

Resistance

 

Temperature

Resistance

 

 

 

 

 

-50

490,813

 

20

46,218

 

 

 

 

 

-40

336,606

 

30

34,558

 

 

 

 

 

-30

234,196

 

40

26,099

 

 

 

 

 

-20

165,180

 

50

19,900

 

 

 

 

 

10

118,018

 

60

15,311

 

 

 

 

 

0

85,362

 

70

11,883

 

 

 

 

 

10

62,465

 

80

9,299

 

 

 

 

 

30

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Lochinvar 399 - 800 service manual Checking temperature sensors, Temperature Resistance

399 - 800 specifications

Lochinvar is known for its cutting-edge water heating and boiler systems, and the Lochinvar 399 - 800 series is no exception. Specifically designed for commercial applications, this series brings advanced technology and engineering to the forefront of hydronic heating solutions.

One of the standout features of the Lochinvar 399 - 800 series is its impressive efficiency. Equipped with a condensing design, these boilers utilize high-efficiency stainless steel heat exchangers that allow for maximum heat transfer while minimizing energy consumption. With an impressive thermal efficiency of up to 96%, the Lochinvar 399 - 800 series stands out in its class, offering significant energy savings and reduced operational costs over time.

Another key characteristic of this series is its robust construction. Designed with longevity in mind, the boilers are built using high-quality materials that withstand extreme temperatures and pressures. The stainless steel design not only enhances durability but also combats corrosion, ensuring a long service life and reduced maintenance costs for users.

The Lochinvar 399 - 800 series also incorporates advanced control technologies. With its intuitive control system, users can easily adjust and monitor heating parameters, ensuring optimal performance and comfort. The integrated Control Wizard feature simplifies the setup process, allowing for quick commissioning and troubleshooting. Additionally, the optional Lochinvar SMART CONTROL technology provides remote monitoring capabilities, allowing operators to keep track of system performance from anywhere.

Versatility is another hallmark of the Lochinvar 399 - 800 series. These boilers come in a range of sizes, with the ability to modulate output based on real-time heating demands. This flexibility ensures that systems can operate efficiently under varying load conditions, making them ideal for schools, hospitals, and commercial buildings requiring consistent hot water availability.

In summary, the Lochinvar 399 - 800 series exemplifies modern boiler technology, combining energy efficiency, durability, advanced controls, and versatility. As businesses and facilities seek to enhance their heating systems, the Lochinvar 399 - 800 offers a reliable and forward-thinking solution for today's energy-conscious environment. Investing in this state-of-the-art boiler system not only improves comfort but also fosters sustainability and cost-effectiveness in commercial heating applications.