Outdoor Knight Boiler Installation & Operation Manual

8 Operating information

Outdoor reset operation

Target temperature with outdoor reset

This feature improves the system's efficiency by decreasing set point as the outdoor temperature warms up. Energy Efficiency Standards require the use of a control that automatically adjusts set point in relation to heat demand. In the absence of an external energy management system, this feature MUST BE used.

See the Outdoor Knight Boiler Service Manual to change the settings.

Reset curve

The reset curve looks at outdoor air temperature and adjusts the set point in relation to heat demand.

Cascade

When multiple boilers are installed, they can be wired together in a cascade sequence. A maximum of eight boilers can be controlled from a single control. In this application one boiler would be designated as the Leader control and all others would be designated as Member controls. The Leader control can be programmed to use Lead/Lag or Efficiency Optimization control methods.

Once the Leader boiler receives a call for heat from a room thermostat, BMS, or ModBus, the control will determine what the set point will be. If outdoor air reset is desired, connect the outdoor air sensor to the terminals on the Low Voltage Connection Board on the Leader boiler. The set point will be calculated based on the programmed reset curve parameters. See the Outdoor Knight Boiler Service Manual to program the reset curve. If outdoor air reset is not desired, do not connect the outdoor air sensor. A fixed temperature set point can be programmed into the control. See page 37 of this manual to program the set point.

If the water temperature at the system supply sensor is less than the set point + the turn-off offset - the off-on differential, then the control will initiate a call for heat on the Cascade (see the Outdoor Knight Boiler Service Manual for an explanation of the offset and differential). The Leader will energize the lead boiler on the Cascade. For a new startup this will be the Leader boiler.

Sequence of the cascade

To equalize the run time of all boilers on the Cascade, the firing sequence will automatically be changed at set intervals.

During the first 24 hours of operation, the sequence will change every hour. After that, the sequence will change every

24 hours. The switching on/off sequence will be as follows:

TIME

SWITCHING ON SEQUENCE

 

 

Start

L-M1-M2-M3-M4-M5-M6-M7

1 hour

M1-M2-M3-M4-M5-M6-M7-L

2 hours

M2-M3-M4-M5-M6-M7-L-M1

 

 

If a boiler locks out or is used to heat an indirect DHW tank, it will automatically be given the lowest priority for the rest of that 24 hour period.

DHW, Night Setback, and Ramp Delay operation with cascade

For Normal Mode DHW operation any boiler(s) in the Cascade can be selected to provide heat for a DHW call. Select a boiler to be designated as the DHW boiler. Connect the DHW thermostat or sensor to the terminals on the Low Voltage Connection Board marked for the corresponding device. When the boiler receives a DHW call, the Leader control will take that boiler out of the Cascade sequence. If another boiler is available, the Leader will start it up to take its place.

The DHW boiler will adjust its set point to the programmed DHW boiler set point and will adjust its firing rate to maintain this. Once the DHW call has been satisfied, the Leader control will place that boiler back into the Cascade sequence.

Switching of the boiler between DHW operation and SH operation when there is a call for both does not occur in Cascade Mode.

When DHW is programmed for Zone Mode, connect the DHW thermostat or tank sensor to the Leader boiler. When a DHW call is received, the Leader will modulate the entire Cascade to bring the system supply temperature up to the DHW boiler set point.

Night Setback operation of the boilers within the Cascade is available. Programming of the Night Setback will be done through the Leader boiler. Refer to the Outdoor Knight Boiler Service Manual for information regarding Night Setback.

Ramp Delay operation of the boilers as described in the Outdoor Knight Boiler Service Manual is available when the boilers are part of a Cascade system.

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Lochinvar 151-286 operation manual Outdoor reset operation, Cascade
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151-286 specifications

Lochinvar 151-286 is a high-efficiency water heater designed for both residential and commercial applications. This model stands out due to its advanced technology, user-friendly controls, and robust construction, making it a reliable choice for those seeking to optimize their hot water supply.

One of the key features of the Lochinvar 151-286 is its impressive heating capacity. With a maximum input of 286,000 BTU/hr, it can efficiently meet hot water demands for a variety of settings, including hotels, restaurants, and other commercial facilities. This substantial output ensures that even during peak usage hours, hot water availability is maximized, reducing wait times and enhancing customer satisfaction.

The water heater utilizes a state-of-the-art condensing technology that maximizes efficiency by capturing and utilizing flue gas heat. This process allows the Lochinvar 151-286 to achieve an impressive thermal efficiency rating of up to 98%. The benefit of such high efficiency translates to significant energy savings and reduced operational costs over time, making it an environmentally friendly option as well.

The Lochinvar 151-286 is equipped with a user-friendly control system featuring advanced microprocessor controls. These controls allow for precise temperature management and monitoring, enabling users to set optimal temperatures according to their specific needs. Additionally, the heater includes built-in diagnostics, allowing for easy troubleshooting and maintenance, which minimizes downtime and extends the life of the unit.

Another standout characteristic of the Lochinvar 151-286 is its durable construction. Built with high-quality materials, including a robust stainless steel heat exchanger, this model is designed to withstand the rigors of daily use. The unit also features a compact design, which facilitates easy installation in various locations, whether it be in a utility closet or alongside existing equipment.

Safety features are paramount in the Lochinvar 151-286, with multiple safeguards in place to protect against overheating and other potential issues. The unit is designed to operate reliably, ensuring peace of mind for users who depend on consistent hot water availability.

In summary, the Lochinvar 151-286 water heater combines high capacity, exceptional efficiency, and user-friendly technology, making it an excellent choice for those seeking reliable hot water solutions. Its advanced features deliver performance and durability that stand out in the competitive market of water heating systems.
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