Lochinvar 90 Electrical connections, Terminal Strip Wiring, Boiler Operating Temperature Control

Page 33

Installation & Service Manual

5Electrical connections

This appliance is wired for 120 VAC service. The appliance, when installed, must be electrically grounded in accordance with the requirements of the authority having jurisdiction or in the absence of such requirements, with the latest edition of the National Electrical Code ANSI/NFPA No. 70. When the unit is installed in Canada, it must conform to the CSA C22.1, Canadian Electrical Code, Part 1 and/or local Electrical Codes.

1.All wiring between the appliance and field installed devices shall be made with type T wire [63° F(35° C) rise].

2.Line voltage wire exterior to the appliance must be enclosed in approved conduit or approved metal clad cable.

3.The pump must run continuously when the appliance is being fired.

4.To avoid serious damage, DO NOT energize the appliance until the system is full of water. Serious damage may result.

5.Provide the unit with proper overload protection.

6.Install a wall thermostat on the inside wall. DO NOT install the thermostat in an area affected by drafts, sunlight, light fixtures, hot or cold water pipes or near a fireplace. See “Terminal Strip Connection of a Room Thermostat” (this page), for proper wiring connection.

Boiler Operating Temperature Control

The operating temperature control is located in the control panel, behind the control panel front access door. The sensing element for the operator is placed in a bulbwell installed in the heat exchanger. Carefully observe the inlet water temperature on the initial boiler on cycles. The exact temperature set point is based on your system’s requirements. Turn the control set point dial to the desired operating water temperature. Observe the boiler discharge temperature after each set point adjustment to ensure proper operation.

Room Thermostat or Remote Thermostat Connection to Terminal Strip

A room thermostat or remote temperature control may be connected to the boiler. The room thermostat should be installed on an inside wall, away from the influences of drafts, hot or cold water pipes, lighting fixtures, televisions, sun rays or fireplaces. Follow the manufacturers instructions supplied with the thermostat for proper installation and adjustment. The boiler is equipped with a terminal strip on the left side of the control panel to allow easy connection (FIG. 5-1).

Remove the jumper between the R and W terminals on the terminal strip. Refer to the chart in this section (Table 5A) to determine maximum allowable length and wire gauge recommended to connect the switching contacts of the room thermostat to the R and W terminals on the terminal strip. Connection to the terminal strip will allow the room thermostat to make and break the 24 VAC boiler control circuit turning the boiler on and off based on the room ambient temperature requirements. Set the boiler operating temperature control as described in this section.

B

DETAIL

A

Figure 5-1_Terminal Strip Connections

TABLE - 5A

TERMINAL STRIP WIRING

 

Wire Gauge

Maximum

 

 

Allowable Length

 

 

 

 

 

 

 

 

 

12 GA

100 ft.

 

 

 

 

 

 

14 GA

75 ft.

 

 

 

 

 

 

16 GA

50 ft.

 

 

 

 

 

 

18 GA

30 ft.

 

 

 

 

 

Power Venter Connection to Terminal Strip

A terminal connection strip is provided for ease of connection for Power Venting Systems, see FIG. 5-1, inset A.

A field supplied powered venter or powered louver/damper may be connected to the boiler via a terminal strip located on the left side of the unit, see FIG. 5-1, inset B.

A 24 VAC relay can be powered from this location when a call for heat has been established. A proving switch can be interlocked back to the appliance to ensure its operation before the appliance is allowed to fire.

Reference the wiring diagrams on pages 63 through 66 of this manual.

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Contents Models 90,000 500,000 Btu/hr Contents Checking equipment Please read before proceedingCodes Copper-fin =B=R Rating RatingsCopper-fin Specifications Gas connection pipe Copper-fin How it worksModels CWN270 Front View Model CWN399 Front View 422 Location of unit Determine unit location3Combustion Air Direct from Outside Determine boiler location6Combustion Air from Outside Single Opening Minimum Recommended Combustion AIR Supply to Equipment Room Venting Conventional Negative Draft Venting SystemVent Pipe Sizes Venting Less from Ridge From Parapet Wall Vertical Vent Termination ClearancesVent Materials Masonry Chimney InstallationSidewall Venting Number7CB with Vent Damper and Vent Damper Terminal Block Automatic Vent DamperGas Supply Gas Pressure Test Gas connectionsGas Connection Manifold PressureGas Piping Install Piping to ControlClockwise to raise regulator gas pressure, counterclockwise Gas Manifold Pressure Adjustment Procedure4Gas Supply Pressure Checking Gas Supply PressureCombination Gas Valves Venting of Combination Gas ValvesTwo Stage Burner Control System Water Flow Switch if equipped Hydronic pipingRelief Valve Low Water Cutoff if equipped Typical Heating Boiler InstallationsMinimum Required Flow For Heating Boiler General Plumbing RulesPiping of the Boiler System System Temperature Rise ChartCirculator Pump Specifications Heat Exchanger Pressure Drop ChartWater Connections Heating Boilers Only Circulator Pump RequirementsPrimary/Secondary Boiler Piping Boiler Flow Rates Three Way Valves4Primary / Secondary Piping of a Single Boiler Primary / Secondary PipingNot to Exceed 4 Pipe DIA or MAX. of 12 Apart 8Multiple Boilers Zoned with Circulators Boiler Operating Temperature Control Terminal Strip WiringPower Venter Connection to Terminal Strip Electrical connectionsTemperature Adjustment Pump Wiring for a Heating BoilerOperating Temperature Control Temperature Control Settings Locating Temperature ControlMaximum SET Point Determination Maximum Set Point DeterminationInlet Water Temperature Sensor Temperature Control SensorsMulti-Purpose Temperature Sensor Outdoor Air Temperature SensorOutdoor Air Reset Option Installation of a Remote Sensor Boiler ApplicationInstallation of a Tank Sensor Water Heater Application Additional Temperature Controls Manual Reset High Water Temperature Limit Control Blocked Vent and Flame Roll-Out / Flame Interlock SwitchPre-start Checklist Start-upInitial Start-up 1Gas Valve 90,000 270,000 Btu/hr Models Lighting InstructionsTo Turn OFF GAS to Appliance Safety Shutoff Test For Standing Pilot Ignition SystemOperating Instructions Intermittent Pilot Spark Ignition System F9/M9 Safety Shutoff Test for Spark Ignition Pilot SystemFreeze Protection To Turn Off Gas to ApplianceFreeze Protection for a Heating Boiler System if required Water TreatmentRequired Temperature Rise Required Temperature RiseDomestic water heaters Domestic Water Heaters 90,000 500,000 Btu/hr ModelsWater Chemistry Softened Water SystemsPump Operation 1Single water heatersingle tank 2Single water heatermultiple tank 3Multiple water heatersingle tank Thermostat Settings Remote Sensor InstallationMinimum Pump Performance Heat Exchanger5Danger Warning Pressure Only Relief Valve Water Flow Switch if equippedThermal Expansion Cathodic ProtectionService technician Maintenance and annual startupOwner maintenance See the User’s Information Manual for instructionsMaintenance Check Relief Valve Check Expansion TankCheck Control Settings Check All WiringCombustion Air Adjustment Perform Start-up and ChecksInspect and Clean Burner Heat Exchanger / Burner AccessInspection and Cleaning Procedure Clear Area Pilot Flame Adjustment ProcedureInspection of Heat Exchanger Waterways Water Circulating PumpGas Train and Controls Review with ownerTroubleshooting Pilot or replace Schematic Diagram F1 Unit DiagramsWiring Diagram F1 Unit 90,000 270,000 Btu/hr ModelsSchematic Diagram F9 Unit Wiring Diagram F9 Unit315,000 399,999 Btu/hr Models Diagrams Diagrams Page Revision a ECO #C06290 initial release CFA-I-S Rev a 09/10
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