8 Field wiring (continued)

Thermostat

1.Connect the room thermostats or end switches (isolated contact only) to room thermostat 1, 2, or 3, as shown in FIG. 8-3.

2.Install the thermostat on the inside wall away from influences of drafts, hot or cold water pipes, lighting fixtures, television, sunlight, or fireplaces.

3.Thermostat anticipator (if applicable):

a.If connected directly to boiler, set for 0.1 amps.

b.If connected to relays or other devices, set to match total electrical power requirements of connected devices. See device manufacturers’ specifications and thermostat instructions for details.

Outdoor temperature sensor

1.Mount the sensor on an exterior wall, shielded from direct sunlight or flow of heat or cooling from other sources.

2.Route sensor wires through a knockout at the rear of the boiler (see FIG. 8-2).

3.Connect the outdoor temperature sensor (FIG. 8-3) to the outdoor sensor terminals on the connection board to enable outdoor reset operation of the Knight XL. Do not install the outdoor sensor.

DHW (Domestic Hot Water) thermostat

Connect storage indirect water heater (DHW) thermostat (FIG. 8-3) to the DHW thermostat terminals on the connection board. If a tank sensor is connected (see DHW Tank Sensor below) the tank thermostat is ignored.

DHW tank sensor

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 the tank set point. The tank sensor included with the Lochinvar Squire® indirect DHW tanks (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.

Installation & Operation Manual

If TST20015 is not compatible with the indirect tank, a tank thermostat can be used to control the boiler. The tank thermostat should be installed per the manufacturer’s instructions and wired to the DHW Thermostat terminals on the low voltage connection board (FIG. 8-3).

Louver proving switch

1.When the operation of the louvers needs to be verified before the boiler 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

1.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).

Low gas pressure switch

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 is used, connect their respective contacts in series, and connect them to the terminals on the connection board (FIG. 8-3).

Variable speed system pump

If a variable speed pump is used in the primary loop, and a 0-10V signal is available from the pump speed control, this signal can be used by the SMART SYSTEM control to anticipate changes in the building heat load. By connecting this 0 - 10V signal to the 0 - 10V SYS PUMP IN terminals, the boiler (or cascade) can modulate up and down as the primary flow increases and decreases.

Boiler pump speed output

This 0 - 10V output is available to control the speed of a variable speed boiler pump. The SMART SYSTEM control will vary the speed of this pump in order to maintain a minimum ΔT across the heat exchanger, as well as prevent high limit lockouts when the flow in the primary loop is extremely low. Connect this output to the 0 - 10V input on the boiler pump speed control.

Rate output

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

￿WARNING

Failure to use the correct sensor may result in the tank temperature being either above or below the set point. Failure to consult the manufacturer of the indirect tank, when the Squire is not used, may result in decreased performance or the risk of scald injury.

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Lochinvar 400, 801 Thermostat, Outdoor temperature sensor, DHW Domestic Hot Water thermostat, DHW tank sensor, Rate output
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400, 801 specifications

The Lochinvar 801,400 is a cutting-edge solution in the realm of high-efficiency commercial water heating. This model represents a significant advancement in the design and functionality of water heaters, catering primarily to the demands of large-scale facilities like hotels, hospitals, and large industrial operations.

One of the standout features of the Lochinvar 801,400 is its impressive heating capacity, which can produce up to 801,400 BTUs, making it suitable for high-demand applications. This output is crucial for establishments that require a consistent supply of hot water, such as commercial kitchens and laundry facilities. The robust design ensures that it can handle peak demand periods without compromising performance.

Another significant aspect is the innovative use of advanced technology in its operation. The Lochinvar 801,400 integrates smart controls that enhance its efficiency and ease of operation. These controls allow for precise monitoring and adjustment of water temperatures, ensuring that the system operates within optimal parameters while maximizing energy savings. The intelligent monitoring system can provide real-time updates, making it easier for facility managers to keep track of performance and address maintenance needs proactively.

The construction of the Lochinvar 801,400 incorporates durable materials that not only enhance the longevity of the unit but also offer resistance to corrosion and wear. This durability translates into lower maintenance costs and an extended lifespan for the unit, making it a worthwhile investment for businesses.

Moreover, the Lochinvar 801,400 is designed with energy efficiency in mind. It boasts a high thermal efficiency rating, which reduces operational costs and minimizes the carbon footprint of heating operations. This efficiency is critical in today’s environmentally conscious market, where businesses are seeking to reduce their energy consumption and comply with strict regulations.

The design of the Lochinvar 801,400 also prioritizes safety, featuring innovative safety controls and fail-safes that protect both the unit and the users.

In summary, the Lochinvar 801,400 offers a combination of high capacity, advanced technology, durability, and energy efficiency, making it an excellent choice for commercial water heating solutions. As industries continue to evolve, the demand for reliable and efficient water heating solutions like the Lochinvar 801,400 will only increase.
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