Thomas & Betts UDAP Door Switch Model Udas only Ignition System, Dip Switch, StatusLED Lights

Page 19

19.Door Switch - Model UDAS only

20.Ignition System

All sizes of Model UDAS heaters are equipped with a door switch which prevents the heater from operating when the service door panel is open. The service panel of a Model UDAS is equipped with a pliable gasket material that fully seals the door to provide added protection from building air entering the combustion zone of the heater. (For switch location, see FIGURE 18, page 31.)

This heater is equipped with a direct spark integrated control module (circuit board). The module monitors the safety devices and controls the operation of the fan and venter motors and the gas valve between heat cycles.

FIGURE 14 – DSI Integrated Control Module (circuit board)

 

x

Spark

 

Transformer

Control Plug

 

Fuse

Thermostat

Connections

Dip Switch

Fan/Blower

Off

Delay

StatusLED Lights

Lights

Flame Status - Yellow LED Codes

Control Status - Green LED Codes

Steady ON

Normal Operation, No call for heat

Fast Flash

Normal Operation, Call for heat

1

Flash

System Lockout, Failed to detect or sustain

 

 

flame

2

Flashes

Pressure Switch Did Not Close within 30

 

 

Seconds of Venter Motor

3

Flashes

High Limit or Flame Rollout Switch Open

4 Flashes

Pressure switch is closed before venter

 

 

motor is energized

Steady OFF

Blown Fuse, No Power, or Defective Board

Steady ON

Flame is sensed

Slow Flash

Weak flame (current below 1.0

 

microamps ±50%)

Fast Flash

Undesired Flame (valve open

 

and no call for heat)

Fan/Blower OFF Delay Settings (dip switches)

SW-1 SW-2 Time

Off

Off

120 seconds (factory setting)

Off

On

90 seconds

On

Off

160 seconds

On

On

180 seconds

Normal Heat Cycle

Operating

Sequence

1)Call for Heat - The thermostat calls for heat by energizing the “W” terminal. The control checks to see that the limit switch is closed and the pressure switch is open. If the limit switch is open, the control responds as defined in the “Abnormal Heat Cycle, Limit Switch Operation”. If the pressure switch is closed, the control will do four flashes on the green LED and wait indefinitely for the pressure switch to open. If the pressure switch is open, the control proceeds to prepurge.

2)Prepurge - The control energizes the venter motor and waits for the pressure switch to close. If the pressure switch does not close within 30 seconds of the venter motor energizing, the control will do two flashes on the green LED. The control will leave the venter motor energized indefinitely as long as the call for heat remains and the pressure switch is open.

Form RZ-NA I-UDA, Mfg #195673 Rev 5, Page 19

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Contents Series Fan-Type Unit Heaters Table of ContentsVenting Manual by Model Installation CodesGeneral Hazard Levels of Warnings in this ManualMassachusetts Requirement Warranty Uncrating and PreparationSize DimensionsModel Udas Separated Combustion Fan Size 100 125 Technical DataClearances Instructions for Changing Pressure SwitchPressure Switch High Altitude OperationModel Udap and Model UDAP-CV Combustion Air applies to Model Udap and ModelHeater Throw Unit Heater LocationLocation Recommendations Model Udas Size 100 125 150 175 225 250 300 350 400 Unit Heater Location cont’dHanging the Heater Model Udap Size 100 125 150 175 225 250 300 350 400Locked to Connectors areRecommended maximum hanger rod length is 6 feet 1.8M Be sure Threaded swivelSizing Gas Supply Line Gas Piping and PressuresGas Connection Size Instructions Two -Stage Valve Manifold Pressure Settings by Altitude for CanadaGas Piping and Pressures cont’d Instructions for High Altitude DerateFeet Meters High Altitude Capacity ChangesThermostat and Connections Burner Electrical Supply and ConnectionsCombustion Air Proving Switch Pressure Switch Combustion Air Proving Pressure Switch SettingsLimit Control StatusLED Lights Door Switch Model Udas only Ignition SystemDip Switch Normal Heat Cycle Operating SequenceSW1 SW2 Time Ignition System cont’dContinuous Fan Operation Fault Modes Gas Valve Fan Motor Fault Modes cont’d LockoutOperating Sequence Wiring DiagramsWiring Diagrams cont’d SW1 Check the installation prior to startup Heater Startup Check Installation and StartupOperating Instructions Operating Sequence Vent System Testing Procedure Model Udap Check installation after startupStartup cont’d Maintenance ScheduleUse only factory-authorized parts Burner Removal Instructions Refer to Figure Heat Exchanger Maintenance Burner MaintenanceBurner Orifice Burner Maintenance cont’dInspect and Clean the Burner Re-Install the Burner Instructions to Re-Install the Burner Refer to FigureDSI Fan Blades IgnitionSystem Cont’dUdas only Combustion Air Pressure SwitchDoor Switch Operating Gas ValveDisconnect Flame Rollout Switch Sizes 30-125 onlySwitch Air System TroubleshootingBurner will General TroubleshootingVenter motor Will not startCont’d Troubleshooting cont’d

UDAP, UDAS specifications

Thomas & Betts is a well-respected name in the electrical and industrial products sector, known for its innovation and quality. Among its impressive portfolio, the UDAS and UDAP series of connectors stand out for their reliable performance and advanced features. These connectors are specifically designed to meet the rigorous demands of electrical applications in various industries.

The UDAS (Universal Disconnect Appliance Switch) and UDAP (Universal Disconnect Appliance Plug) are engineered for high-capacity applications where safety, efficiency, and ease of use are paramount. One of the main features of these connectors is their ability to deliver increased electrical resistance and durability. They are constructed from high-quality materials that can withstand extreme environmental conditions, making them ideal for outdoor and harsh industrial applications.

Another key technology employed in the UDAS and UDAP series is the quick-connect mechanism. This innovative design allows users to connect and disconnect circuits swiftly without requiring excessive force or complex tools. This is particularly beneficial in settings where downtime must be minimized and efficiency is crucial. Additionally, the connectors are designed to provide a secure, locking fit to ensure consistent electrical contact, thereby enhancing operational safety.

The UDAS and UDAP connectors are manufactured to comply with several industry standards, ensuring that they meet or exceed the requirements for electrical safety and performance. Their user-centric design features help in reducing installation time and costs, making them a preferred choice among contractors and engineers.

Furthermore, these connectors are versatile, compatible with a wide range of electrical systems, and can be employed in applications such as HVAC, lighting, and power distribution. They also come in various sizes and configurations to accommodate diverse specifications, improving customization options for different projects.

In summary, the Thomas & Betts UDAS and UDAP series stands out for their robust design, quick-connect technology, and versatility across various industrial applications. Their durability and compliance with safety standards make them an excellent choice for professionals seeking reliable connectivity solutions in demanding environments. Investing in these connectors ensures optimal performance and safety in electrical installations, showcasing Thomas & Betts' commitment to excellence in electrical components.
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