Lochinvar 999 - 750, CF-CH(E)-i&s-08, 399 service manual Sequence of Operation

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Hydronic Heating Boilers and Domestic Water Heaters

SEQUENCE OF OPERATION Continued

MANUAL RESET HIGH-LIMIT THERMOSTAT

A manual reset high limit thermostat is provided as backup for the electronic adjustable temperature controller. An adjustable dial thermostat will trip and require resetting should water temperature exceed its settings. When tripped, all controls remain powered, but 24VAC is prevented from being delivered to the ignition module’s thermostat input.

EMS/SEQUENCER/REMOTE AQUASTAT TERMINALS

The EMS/sequencer/remote aquastat terminals are provided for connection of the unit to an external energy management system or sequencer and are located along the top edge of the terminal strip located within the electrical wiring box. In addition to providing a means to externally stage fire the unit, these terminals also provide for remote shutdown and override by routing through dry contacts from external devices. Connection of the external dry contacts to these terminals requires the removal of one or more factory installed jumpers located on the terminal strip.

SAFETY DEVICE TERMINALS

The safety device terminals ensure that no power can be delivered to the ignition module unless factory/field-installed safety devices such as flow switches and gas pressure switches are closed. These safety device terminals are located below the EMS/Sequencer/Remote Aquastat terminals located within the electrical wiring box.

Two types of connections are offered: Continuous terminals provide for connection of safety devices that are desired to be constantly monitored. Intermittent terminals are provided for devices that are only monitored during a “call for heat” cycle. Connection to either of these terminals requires the removal of a factory-installed jumper located on the terminal strip.

ELECTRONIC TEMPERATURE CONTROLLER

(Operator) A multiple stage electronic temperature controller is provided on the unit and it serves to maintain a user selectable temperature set point. In addition to maintaining a set point, it can provide for various desired modes of operation. Ultimately, the temperature controller delivers 24VAC to the ignition module and pressure switch when it senses heat mode is desired.

IGNITION MODULE

(Controlled by Electronic Temperature Controller)

Upon sensing the 24VAC delivered to the ignition module by the electronic controller, the ignition modules check for a shorted

pressure switch and then, provided the air switch isn’t shorted, supplies 120VAC to its blower output relay and waits for a pressure switch signal.

TWO SPEED BLOWER(S)

(Controlled by Ignition Module and Relay Board)

Two-speed blower(s) serve to provide combustion air to the unit. The blower is provided with a high and low speed tap. Depending upon the number of stages in operation, a blower’s speed may increase or decrease accordingly. Stage 2 will increase the blower’s speed to high.

PRESSURE SWITCH

(Activated by Blower Turning On)

One pressure switch is provided per blower to monitor its on/off operation. Upon a call for heat, 24VAC is delivered to the pressure switch. If the blower being monitored generates adequate air pressure, the pressure switch closes to deliver 24VAC to their respective ignition module’s pressure switch monitoring input terminal.

PREPURGE

(Ignition Module Function)

Once an ignition module sees a 24VAC input from its pressure switch, it runs the blowers for approximately 15 seconds in order to purge the combustion chamber of any unburned fuel/air mixture.

TRIAL FOR IGNITION

(Ignition Module Function)

Once an ignition module has completed its prepurge period, it turns on a hot surface igniter. Once the hot surface igniter’s current draw reaches a proper level, the ignition module begins a trial for ignition period of approximately 25 seconds to allow time for the igniter to reach the ignition temperature necessary to ignite the fuel/air mixture.

IGNITER

(Controlled by Ignition Module)

One igniter per ignition module is provided in order to ignite the fuel/air mixture and its on/off operation is controlled by the ignition module.

RELAYS

(Controlled by Electronic Temperature Controller and Ignition Module)

A relay is provided to switch each blower from low to high speed and to deliver power from the primary stages to the secondary stages depending upon the electronic thermostat’s settings. The relay also serves to override the pressure switch proving function of the second ignition control (if equipped) to activate during a call for heat because both blowers run whenever any or all stages

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Contents Domestic Water Heaters Hydronic Heating Boilers and Domestic Water Heaters General Product Information UnpackingSafety Information Installation Installation Clearances from Combustible ConstructionOutdoor Boiler Installation LocationFreeze Protection Pump OperationShut-Down and Draining Freeze Protection for a Heating Boiler System if requiredCombustion and Ventilation AIR Combustion Air FilterCombustion Air Options Outside Combustion Air, No DuctsCombustion Air from Interior Space Venting Exhaust FansGeneral Information Vertical Vent Termination Clearances and LocationSidewall Vent Termination Clearances and Location ChimneyCombustion Air Inlet Piping Length of Air Inlet PipeSidewall Air Inlet Vertical Rooftop Air Inlet ClearancesVent System Options Combined Air Inlet PointsBarometric Damper Location Conventional Negative Draft Venting Negative DraftFlue Outlet Piping Vertical DirectAire Venting Vertical Vent Termination Clearances and LocationInstallation Vent Kits Venting of Flue ProductsSidewall Venting Sidewall FanSidewall Venting Termination Sidewall Venting Without FanVenting Guidelines Masonry Chimney Installation Horizontal DirectAire VentingVent Kits Direct VentingVertical DV Venting Termination Connecting the Air Inlet Pipe to the Unit Horizontal DV Venting TerminationFlue Pipe Materials Combustion Air Inlet PipingAir Inlet Piping Materials Sealing PVC, CPVC, ABS, Dryer Vent, and Flex Duct Vent PipeOutdoor Installation Venting MaximumOutdoor Vent/Air Inlet Location Outdoor Vent Cap KitConnecting to GAS Supply Connecting Gas Piping to UnitGas Piping Gas Pressure TestGas Train and Controls TABLE-JBtu/hr Distance From Meter in feet Input 51-100 101-200 201-300 301-500Combination Gas Valves Checking Gas Supply PressureVenting of Combination Gas Valves Gas Manifold Pressure Adjustment Multiple Unit Installations Gas Supply Pipe SizingTable L Connecting to Water Supply Water Flow Switch Relief ValveLow Water Cutoff General Plumbing Rules Water Connections Heating Boilers OnlyCirculator Pump Requirements Heat Exchanger Pressure Drop Chart Circulator Pump SpecificationsPump Installation and Maintenance Primary/Secondary Boiler PipingLow Temperature Return Water Systems Table O LTV Valve KitsInput LTV Valve Kit Btu/hr Radiant Floor and Snow Melt Heating Systems 10ºF 20ºF 30ºF 40ºFTemperature/Pressure Gauge Boiler Flow RatePlacing the Boiler in Operation Boiler Bypass RequirementsInstallation with a Chilled Water System Boiler Operating Temperature ControlWater Treatment Terminal Strip Connection OptionsFor Your Safety Read Before Operating Remote ON/OFF Boiler or Water HeaterOperation Power Up Quick Programming OverviewTo Turn Off Gas To Appliance Standard Btu/hr ModelsAdjust Menu Setting Descriptions Adjust Menu Settings for Operating ModesTABLE-Q TABLE-RIgnition Systems and Stages Operating ModesProgramming Buttons Access Levels Temperature ControlPlacement of Sensors Graphic Symbols Programming For Mode 1, Boiler OperationStaging Logic Programming For Mode 2, Water Heating Operation Programming For Mode 3, Sequenced OperationRemote Mounting of Sensors TABLE-SError and Warning Messages HOT Surface Ignition SystemHot Surface Igniter and Ignition Control Module Hot Surface Ignition Control ModuleDiagnostic Status Indication Access to Internal Control PanelIgnition Control Diagnostic Codes Removing the Control PanelOperation and Diagnostic Lights Status LED Diagnostic CodesIgnition and Control Timings Hot Surface Ignition Module Timings NominalRequired Temperature Rise Temperature Rise ChartWater Velocity Control Water ChemistryPipe Size Requirements Circulating PumpTABLE-X 399,999 750,000 Btu/hr ModelsPotable Hot Water Temperature Control Settings Minimum Pump PerformanceHeat Exchanger TABLE-YHigh Water Temperature Limit Control Optional Relief ValveThermal Expansion Location of Cold Water Supply Piping ConnectionsFlue Gas Passageways Cleaning Procedures Burner Removal and CleaningAppliance Area Water Circulating PumpHeat Exchanger Cleaning ElectricalCombustion and Ventilation Air Adjusting Differential Air Pressure Set Up ProcedureAdjustment Procedure Servicing Hot Surface Igniter and Ignition Module Ignition System CheckoutSequence of Operation Ignition Troubleshooting Guide 990,000 2,070,000 Btu/hr Models Domestic Water Heaters Hydronic Heating Boilers Ladder Diagram 399,999 750,000 BTU/HR Models Hydronic Heating Boilers and Domestic Water Heaters Installation Ladder Diagram 990,000 2,070,000 BTU/HR Models Models Wiring Diagram Hydronic Heating Boilers and Domestic Water Heaters BTU/HR Models
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399, CF-CH(E)-i&s-08, 999 - 750 specifications

Lochinvar 999 - 750, CF-CH(E)-i&s-08,399 is a cutting-edge boiler designed for commercial heating applications. With its robust construction and high efficiency, this model stands out in the crowded market of heating solutions.

One of the main features of the Lochinvar 999 - 750 is its exceptional thermal efficiency rating. The unit incorporates advanced condensing technology that allows it to recover heat from flue gases, which helps in achieving efficiency levels of up to 99%. This efficiency not only reduces energy consumption but also lowers operational costs, making it an excellent investment for businesses looking to minimize their carbon footprint.

The boiler is designed to provide a powerful output of 750 kW, ensuring it meets the heating demands of larger buildings or commercial spaces. Its capacity makes it suitable for a range of applications including schools, hospitals, and industrial facilities. Moreover, the unit features a built-in cascading system that enables multiple boilers to be connected, enhancing system reliability and flexibility.

In terms of technology, the Lochinvar 999 - 750 is equipped with a user-friendly touchscreen interface. This innovative control system allows operators to monitor and adjust settings with ease, providing real-time performance data and alerts for maintenance needs. The intelligent controls optimize operation to match the heating load, further enhancing energy efficiency.

Safety is a top priority with this model. It is built with multiple safety features such as automatic shut-off valves, pressure relief valves, and flame monitoring systems, ensuring safe operation under various conditions. The unit also adheres to stringent industry standards and regulations, making it a reliable choice for commercial applications.

Furthermore, the Lochinvar 999 - 750 is designed with serviceability in mind. Its compact footprint and accessible components simplify maintenance, reducing downtime and associated costs. The unit also supports a variety of fuel sources, including natural gas, propane, and biodiesel, providing flexibility to meet different facility requirements.

In summary, the Lochinvar 999 - 750, CF-CH(E)-i&s-08,399 represents a blend of efficiency, reliability, and safety in commercial heating. Its advanced technologies and thoughtful design make it a powerful solution for various heating needs, making it an ideal choice for businesses aiming for excellence in energy management and operational efficiency.
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