1 Service (continued)

DHW Settings

DHW Boiler Set Point

When a DHW call for heat becomes active, the control will use the DHW boiler set point to determine the firing rate of the boiler based on the boiler outlet water temperature, or system temperature when DHW is programmed as a zone.

This parameter can be changed by the installer by accessing the DHW Boiler Set point parameter. The temperature range of this parameter is 68°F (20°C) to 180°F (82°C). The default value is 180°F (82°C).

DHW Tank Set Point

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 below the tank set point differential (Tank Set point Differential parameter), and finishes the call for heat when the tank temperature reaches tank set point + offset. This parameter can be changed by the installer by accessing the DHW Tank Set point parameter. The temperature range of this parameter tank minimum set point to tank maximum set point. The default value is 125°F (52°C).

Tank Set Point Differential

When a tank sensor is installed, the tank temperature must drop this amount below the tank set point (DHW Tank Set point parameter) before the boiler turns back on. The installer can adjust this setting by accessing the Tank Set point Differential parameter. The minimum setting is 0° (0°C), and the maximum is 40°F (22°C). The default setting is 6°F (3°C).

DHW Boiler Offset

This parameter reflects the degrees above DHW boiler set point the temperature has to go before the boiler will shut off. The range is 0°F (0°C) to 40°F (22°C). The default setting is 10°F (6°C).

DHW Boiler Differential

This parameter reflects the degrees below DHW boiler set point the temperature has to go before the boiler turns back on. The range is 0°F (0°C) to 60°F (33°C). The default setting is 20°F (13°C).

SH/DHW Switching Time

When a boiler has a space heating demand and it receives a DHW demand, it will immediately switch to the DHW demand and start a timer. Once the timer has expired, the boiler will switch back to the space heating demand and start another timer. Once this timer expires, it will switch back to the DHW demand. The installer can adjust the length of time the boiler will service the space heating demand by accessing SH/DHW Switching Time parameter. The minimum setting is 0 minutes and the maximum setting is 50 minutes. The default time is 30 minutes.

Service Manual

DHW/SH Switching Time

When a boiler has a DHW demand and it receives a space heating demand, the SMART SYSTEM control will start a timer. Once the timer expires, it will stop the DHW demand and service the space heating demand. The installer can adjust the length of time the boiler will service the DHW demand by accessing the DHW/SW Switching Time parameter. The minimum setting is 0 minutes and the maximum setting is 50 minutes. The default setting is 30 minutes.

Tank Minimum Set Point

This setting controls the minimum tank set point for the tank temperature. The installer can adjust this by accessing the Tank Minimum Set point parameter. The minimum setting is 60°F (16°C) and the maximum setting is the maximum tank set point (Tank Maximum Set point parameter). The default value is 60° (16°C).

Tank Maximum Set Point

This setting controls the maximum tank set point for the tank temperature. The installer can adjust this by accessing the Tank Maximum Set point parameter. The minimum setting is the minimum tank set point (Tank Minimum Set point parameter) and the maximum setting is 190°F (88°C). The default value is 140°F (60°C).

DHW Type

This parameter determines whether the Knight boiler treats the indirect DHW tank as a separate load, or as a zone on the primary loop. When programmed as a separate load, the boiler will turn on the DHW pump and then turn off the boiler pump when an indirect DHW demand begins. When programmed as a zone, the boiler will turn on the DHW pump, leave the boiler pump on and change the system set point to the DHW boiler set point (DHW Boiler Set point parameter).

This setting may be changed by the installer by accessing the DHW Type parameter. The choices are NORMAL and ZONE. The default setting is NORMAL.

Fan Speed Limiting for Indirect DHW Tank

This parameter determines the maximum fan speed (and therefore the maximum rate) to be used when heating an indirect DHW tank. This setting may be used when the tank is unable to accept all of the BTU’s available from the boiler. This parameter may be adjusted by the installer by accessing the Fan Speed Limiting for Indirect DHW Tank parameter. The default value is the maximum fan speed for that model.

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Lochinvar 81-286 service manual DHW Settings
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81-286 specifications

Lochinvar 81-286 is a highly efficient and innovative heating solution that represents the latest advancements in boiler technology. This model, part of Lochinvar's prestigious line-up, is designed for commercial applications, delivering superior performance while emphasizing energy efficiency and user-friendly operation.

One of the standout features of the Lochinvar 81-286 is its robust construction. Built with high-quality materials, the unit is engineered for durability and reliability, ensuring long-term operation with minimal maintenance. Its compact design allows for versatility in installation, making it suitable for various building layouts and configurations.

The boiler's primary technology is its advanced condensing capability, which optimizes heat transfer and reduces energy consumption. By efficiently using the heat generated during combustion, the 81-286 can achieve higher thermal efficiencies, often surpassing traditional systems. This results in lower operating costs and reduced greenhouse gas emissions, aligning with the growing demand for sustainable energy solutions in commercial buildings.

Lochinvar incorporates intelligent control systems into the 81-286, featuring user-friendly interfaces that facilitate straightforward programming and monitoring. These control systems enable precise regulation of temperature and pressure, ensuring optimal operation while providing real-time feedback that aids in troubleshooting and maintenance. Users can enjoy the convenience of remote monitoring, enhancing the overall user experience.

Another key characteristic of the Lochinvar 81-286 is its capacity range. The model is available in various sizes, allowing it to meet the specific demands of different facilities, from small businesses to large industrial applications. This flexibility makes it a top choice for contractors and engineers seeking reliable heating solutions that cater to diverse needs.

In addition, the Lochinvar 81-286 boasts exceptional safety features, including built-in safeguards that protect against overheating and pressure surges. These aspects ensure that the unit operates within safe parameters, providing peace of mind for facility managers and operators.

In summary, the Lochinvar 81-286 combines durability, efficiency, and advanced technology, making it an ideal solution for commercial heating needs. With its innovative condensing design, intelligent controls, and safety features, this boiler stands out as a reliable choice for those seeking sustainable and effective heating solutions. Its versatility and performance make it a key player in today’s ever-evolving energy landscape.
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