Lochinvar 400-801 operation manual Operating information, General, How the boiler operates

Page 39

8 Operating information

General

How the boiler operates

The Outdoor Knight XL uses an advanced stainless steel heat exchanger and electronic control module that allows fully condensing operation. The blower pulls in air and pushes flue products out of the boiler through the heat exchanger and flue piping. The control module regulates blower speed to control the boiler firing rate. The gas valve senses the amount of air flowing into the boiler and allows only the right amount of gas to flow.

How the control module operates

The SMART SYSTEM control module receives inputs from boiler sensors and external devices. The control module activates and controls the blower and gas valve to regulate heat input and switches the boiler, Domestic Hot Water (DHW), and system pumps on and off as needed. The user programs the module to meet system needs by adjusting control parameters. These parameters set operating temperatures and boiler operating modes. Boiler operation can be based on boiler outlet water temperature, boiler inlet water temperature, system temperature, a 0 - 10V signal, or Modbus, depending on the parameter settings.

Control inputs and outputs

Room thermostat

There are three (3) heat/loop demand connections available on this control. These inputs tell the boiler to provide water for space heating. Each demand connection has its own set point and outdoor air reset curve. When multiple demands have a call for heat the control will give priority to the demand with the highest set point.

Example: Assume that both heat/loop demand 1 and heat/ loop demand 2 have a call for heat. Demand 1 has a set point of 110°F. Demand 2 has a set point of 140°F. The boiler will regulate the system temperature to 140°F until Demand 2 has been satisfied. Once Demand 2 has been satisified the boiler will provide 110°F water to the system.

￿CAUTION When multiple temperature loops are used, mixing valves are required for the

protection of any low temperature loops.

SMART SYSTEM Multi-temp loop control

The Outdoor Knight XL boiler is capable of producing up to three (3) set point temperatures to meet different space heating demands. This device controls the temperatures of up to three (3) separate loops, based on the settings for the three (3) heat/loop demands (reference Lochinvar kit RLY30086).

0 - 10V input (set point or power)

The Outdoor Knight XL can be controlled by a Building Management System (BMS) using a 0 - 10 VDC signal. The control can be configured by the installer to use this signal to either control set point or firing rate.

Outdoor Knight XL Installation & Operation Manual

The Outdoor Knight XL can also be programmed to accept a call for heat from a 0 - 10V signal, reference the Outdoor Knight XL Service Manual for a detailed explanation of this procedure.

DHW priority

The SMART SYSTEM control allows the connection of a DHW thermostat or tank sensor to the low voltage connection board. When a tank sensor is connected, the DHW thermostat input is ignored. When a boiler is programmed for DHW Normal Mode, the maximum firing rate can be limited to match the input rating of the indirect tank coil.

DHW / space heating (SH) cycling

If a DHW call for heat is received while a space heating call is in progress, and the DHW is in Normal Mode, the control will start the DHW pump and shut the boiler pump off. The system pump will remain on. For stand-alone boilers, if the space heating call is still active while the DHW call is in operation, the control will wait for 30 minutes (time adjustable by installer) then it will switch back to the space heating demand. There is a timer to switch from space heating to DHW and a timer to switch from DHW to space heating. The control will switch back and forth until one of the heat demands end. This function does not apply to cascade systems.

Programmable controlling sensor

The control module is programmed to use the outlet sensor as the control sensor by default. If a system supply sensor is connected, the control automatically uses it as the control sensor. For stand-alone boilers, the control sensor can be changed by the installer to the inlet sensor. If the inlet sensor is chosen as the controlling sensor, it is recommended that the system supply sensor be installed in the system supply in order to provide the best control of the inlet temperature.

Anti-cycling

After the burner turns off, the control will delay the next burner cycle for a set time period (time is adjustable by the installer). The time delay will be bypassed if the inlet water temperature drops too far during the delay.

Boiler and system pump control

The boiler pump will run whenever the burner is firing, unless the DHW is programmed for Normal Mode and the boiler is heating the DHW tank. The boiler pump will run during Freeze Protection Mode as well. It will continue to run for a short time after the burner turns off or the Freeze Protection Mode ends.

The system pump will run whenever there is a space heating call for heat, or the boiler goes into Freeze Protection Mode. It may be programmed to run during a DHW call for heat when the DHW is programmed for Zone Mode. It will continue to run for a short time after the end of the heat demand or the Freeze Protection Mode. The system pump can be programmed to run continuously if desired, except during outdoor shutdown and/ or a DHW call for heat.

39

Page 38 Page 40
Image 39
Page 38 Page 40
Contents Outdoor Knight XL Models 400 Contents Please read before proceeding When servicing boilerStainless steel heat exchanger Outdoor Knight XL How it worksModel Models 601 Outdoor Knight XL Boiler Ahri Rating RatingsInstallation must comply with Determine boiler locationBefore locating the boiler, check Prevent combustion air contamination Provide clearancesOutdoor vent / air intake location Flooring and foundationInstall flue pipe assembly Models 400 Prepare boilerRemove boiler from wood pallet Models 701 3Install flue pipe assembly Models 701Gas conversions Model 4Installing Propane Orifice ModelLeveling the boiler Models 601Hydronic piping TEE with 1 Fitting on TOP Nipple Close Nipple Near boiler piping components Flow switch adjustmentNear boiler piping connections Circulator sizingVariable speed pump option Head Feet Pressure20F 25F 30F 35F Model 7Single Boiler Multiple Temperatures 8Single Boiler Primary/Secondary Piping Manifold Pipe Sizes in Inches mm Number of Units10Multiple Boilers Primary/Secondary Piping Temperature Wires to Loop Sensors 120VAC to Gas connections Connecting gas supply pipingPropane Gas Natural gasInches Check inlet gas supplyGas pressure Gas valve replacementLow voltage connections Field wiringInstallation must comply with Line voltage connectionsThermostat Outdoor temperature sensorHigh gas pressure switch Low gas pressure switchModBus Flow switchAlarm contacts Wiring of the cascade3Low Voltage Field Wiring Connections Condensate drain Condensate disposalFill and test water system Freeze protection when usedStart-up Check/control water chemistryInspect/check condensate lines and fittings Check for gas leaksCheck thermostat circuits Inspect/fill condensate systemCheck system and boiler Final checks before starting the boilerStart the boiler If boiler does not start correctlyFor Your Safety Read Before Operating Natural Gas Propane Set space heating operationVerify DHW mode Set domestic hot water DHW operationConfiguration of the cascade How the control module operates Operating informationGeneral How the boiler operatesProtection features Temperature controlBoiler temperature regulation Cascade Outdoor reset operation, if usedOperation Display Sequence of operationStandby, ready to start a new cycle User Access modesInstaller Outdoor Knight XL control moduleCall for Heat Information Dial Function Maintenance Maintenance and annual startup Service technicianOwner maintenance Maintenance Check boiler relief valve Flue vent system and air pipingCheck water system Check expansion tankInspect ignition and flame sense electrodes Check ignition ground wiringCheck all boiler wiring Check control settingsModel Kit Part Component Number Description Check flame signalCleaning boiler heat exchanger Review with ownerHigh Voltage Diagrams2Ladder Diagram
Related manuals
Manual 48 pages 50.5 Kb

400-801 specifications

The Lochinvar 400-801 is a high-efficiency commercial boiler that embodies advanced engineering and cutting-edge technology. Designed for a variety of commercial applications, this boiler is known for its reliability, efficiency, and robust performance.

One of the standout features of the Lochinvar 400-801 is its high thermal efficiency, which can reach up to 99%. This efficiency not only reduces fuel consumption but also lowers operating costs, making it an economical choice for businesses seeking to minimize overhead. The boiler employs a stainless steel fire-tube heat exchanger that ensures optimal heat transfer and durability. This construction allows for enhanced resistance to corrosion, thereby extending the boiler's lifespan.

The Lochinvar 400-801 is equipped with advanced control technologies that enhance its performance. With its built-in SMART SYSTEM control, users can easily monitor and manage the boiler’s operations, optimizing performance while ensuring ease of use. This control system features a user-friendly interface that provides real-time data, including temperature settings, pressure readings, and operational status, allowing for quick diagnostics and efficient troubleshooting.

Safety is paramount in the design of the Lochinvar 400-801. The boiler includes a comprehensive safety system that incorporates multiple safety interlocks and a venting system that prevents backflow and ensures safe exhaust. Moreover, the unit is designed to operate with minimal noise, making it suitable for environments where noise reduction is crucial.

Installation and maintenance of the Lochinvar 400-801 are straightforward, thanks to its compact design and multiple venting options. The low-profile construction allows for flexibility in placement, making it an ideal fit for tight spaces. Maintenance tasks are simplified with accessible components, minimizing downtime and ensuring the system operates efficiently over its lifespan.

In conclusion, the Lochinvar 400-801 stands out in the commercial boiler market with its blend of efficiency, reliability, and innovation. With its advanced technologies and features, businesses can achieve significant energy savings while ensuring comfortable and consistent heat for various applications. The Lochinvar 400-801 is an investment in quality and performance, backed by a well-established brand in the heating industry. Whether for a new installation or a replacement, this boiler offers a comprehensive solution for commercial heating needs.
Top Page Image Contents