Installation & Operation Manual

8 Field wiring (continued)

 

Tank thermostat

Low gas pressure switch

1.Connect the tank thermostats (isolated contact only) to the tank thermostat contacts as shown in FIG. 8-3.

Tank sensor

1.By installing a tank sensor, the SMART SYSTEM control can perform the tank thermostat function. The SMART SYSTEM control automatically detects the presence of this sensor and generates a DHW call for heat when the tank temperature drops 6°F (3°C) below the tank set point and finishes the call for heat when the tank temperature reaches 3°F (1.5°C) above the tank set point.

2.The tank sensor TST20015 is the only sensor suitable for use with the SMART SYSTEM control. Connect the sensor leads to the Tank Sensor terminals on the Low Voltage Connection Board (FIG. 8-3). Consult the tank manufacturer for application and performance when

used with any other indirect tank.

Louver relay

If louvers need to operate when the water heater fires, they can be controlled by this output. Connect these terminals to a 24 VAC relay coil, which is wired to operate the louvers (FIG. 8-3).

Louver proving switch

When the operation of the louvers needs to be verified before the water heater fires, remove the jumper wire from these terminals and connect them to the normally open contacts on its proving switch (FIG. 8-3).

High gas pressure switch

If a switch is provided to detect excessive gas pressure, remove the jumper wire from the terminals on the connection board, and then connect them to its normally closed contacts (FIG. 8-3).

1.If a switch is provided to detect low gas pressure, remove the jumper wire from the terminals on the connection board and connect them to its normally open contacts (FIG. 8-3).

2.If both a high and low gas pressure switch are used, connect their respective contacts in series, and connect them to the terminals on the connection board (FIG. 8-3).

NOTICE

See Section 7 - Gas Connections for a detailed

explanation regarding high and low gas

 

pressure switch operation.

Flow switch

1.A flow switch is used to guarantee flow through the water heater before allowing it to fire. The flow switch must be installed at the water heater outlet.

2.Connect these terminals to the normally open contacts on the flow switch (FIG. 8-3).

Rate output

This output provides a 0 - 10V signal that is proportional to the firing rate of the water heater. This may be used by a BMS system to monitor the actual rate of the water heater.

ModBus

When the optional ModBus interface module is installed, the RS-485 ModBus cable is connected to these terminals. Use shielded, 2-wire twisted pair cable. If desired, the shield can be connected to ground by installing a jumper wire between terminals 1 and 3 on connector X5 on the optional ModBus interface module.

Water heater Building Management System (BMS)

1.An external control may be connected to control either the firing rate or the set point of the water heater. If the external control uses a set of contacts to enable the water heater, connect the contacts to the Tank Thermostat terminals. Otherwise, the SMART SYSTEM control will be enabled by the 0-10V signal.

2.Make sure the ground terminal is connected to the ground output terminal of the external control, and the 0 - 10 VDC terminal is connected to the 0 - 10 VDC terminal of the external control.

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Lochinvar 151 Tank thermostat Low gas pressure switch, Tank sensor, Louver relay, Louver proving switch, Flow switch
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151 specifications

Lochinvar 151,286 is a notable model in the realm of commercial water heating solutions, designed primarily for large-scale applications. This model incorporates advanced technologies and features that set it apart in terms of efficiency, usability, and reliability.

One of the hallmark features of Lochinvar 151,286 is its high-efficiency system that leverages condensing technology. This technology enables the unit to extract additional heat from exhaust gases, allowing it to operate at an impressive annual fuel utilization efficiency (AFUE) rating. This not only reduces energy consumption, but it also significantly lowers operational costs.

The Lochinvar 151,286 is equipped with a robust stainless steel heat exchanger, which provides both durability and enhanced thermal efficiency. This design withstands the rigors of high-demand environments, making it ideal for restaurants, schools, hospitals, or any facility requiring consistent hot water supply. Its compact footprint allows it to be installed in tight spaces without sacrificing performance.

Another standout characteristic is its intelligent control system. The built-in touchscreen interface offers users an intuitive way to manage settings, monitor performance, and troubleshoot issues. This smart technology aids in simplifying maintenance and improves overall system reliability. The unit also features advanced safety protocols, including multiple sensors that monitor operation and provide alerts in case of irregular performance.

In terms of capacity, the Lochinvar 151,286 can deliver an impressive output, accommodating varying demands with ease. Its innovative modulation capabilities allow the unit to adjust its heating output based on real-time hot water needs, ensuring unmatched comfort and efficiency.

Supporting the model’s performance are versatile connectivity options. Lochinvar 151,286 can integrate seamlessly with building management systems, allowing facility managers to monitor and control heating processes remotely. This level of connectivity not only enhances control but also supports energy-saving strategies across the facility.

In conclusion, Lochinvar 151,286 stands out as a premium choice for commercial water heating needs. With its high-efficiency ratings, durable construction, intelligent control system, impressive capacity, and versatile connectivity, it ensures that hot water is delivered reliably and efficiently, meeting the demands of modern businesses while reducing energy costs. This combination of technology and design makes it an essential component for any large-scale facility focused on performance and sustainability.
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