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NORA Oilheat Technicians Manual

within approximately 5 seconds after “valve delay-on,” the control shuts the burner “off on safety.” • If the cad cell loses sight of the flame at any time during the firing cycle, the control immediately closes the oil valve to prevent oil flow, then goes back into “valve-delay-on” mode and makes one attempt to relight. Safety check • Turn off the service switch • Remove the control box from the sub-base • Remove the cad cell from the control box • Replace the control box on the sub-base • Turn on the service switch and make sure that the line voltage circuit is complete The control should energize and the burner should “go off on safety” approximately 5 seconds after the “valve-delayon” cycle. If the control does NOT “go off on safety”, replace it and be sure to check the timing on the new control. Troubleshooting tips In general, it is good practice to check that the control box spades and sub-base terminals are making good contact, and to verify that there is between 42 and 52 Volts AC between terminals 3 and 7 while the motor is running. If the burner stays in “valve-delay-on,” check for the following before you condemn the control: • Cad cell faulty or sensing light before “trial for ignition.” • Coil wires are reversed on Terminals 1 and 2 or on Terminals 1 and 8. • Open coil circuit, Terminals 2 and 8. To check this, connect your ohmmeter between terminals 2 and 8; if the coil circuit is open, the reading will be 0 ohms. • Open coil circuit, Terminals 1 and 2. Reading should be 1235 ohms or less. • Note—this is for the 530 SE primary control only. An open coil circuit on Terminal 1 will cause the 483 SE control to lock out. • Insufficient voltage between Terminals 3 and 7. It should read 42 to 52 Volts AC. If you have lower voltage, check the incoming supply. If there is proper incoming voltage, above 102 Volts AC, change the burner motor. If a burner with a 530 SE control continues to purge and light off with immediate flame dropout, or a burner with a 483 SE control cycles on and off in quick succession, check the following: • The metal yoke for the coil may be missing or improperly installed. • Coil wires 2 and 8 may be reversed. • There may be low resistance on the coil holding circuit, terminals 1 & 2. Resistance should be 1350 ohms, plus or minus 10%. If the resistance is low, change the coil. The following pages show reference guides for the Riello primary control. Chapter 11 Primary Controls Chapter 11—Primary Controls 11-17


NORA Oilheat Technicians Manual
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