Royal Appliance Air Furnace A, RT

29733 R2 06/01/2003

Thermostat is calling for heat, burner is not running.

Reset control box.

Burner Starts Burner Does Not Start

Test for 120 Vac Supply at sub-base between L and N or terminals #3 and #5.

120 Vac No Voltage

· Check system fuse, ensure service switch is ON.

· Verify that all control limits are closed.

· Verify 24 Vac at T-T on switching relay.

Turn off power supply. Remove control

box and jumper terminals #5 and #6.

Restore power.

Motor Runs Motor Does Not Run.

· Verify reduced voltage (42 – 52 Vac

between terminals #3 and #7.

· Ensure good contact between control box

spades and sub-base terminals.

· Defective control box / Replace.

· Verify electrical connections.

· Check for seized pump, motor, or fan

against housing.

· Defective motor capacitor.

· Thermal Overload (Hot motor).

Burner stays in Pre-purge

· Faulty CAD cell or seeing light before trial for ignition.

· Coil wires on terminals #1 and #2 or #1 and #8 reversed.

· Open coil circuit; terminals #2 and #8.

· Open coil circuit; terminal #1

· Defective 42 – 52 Vac supply, terminals #3 and #7.

· Defective control box / Re

lace.

Burner Continues to Purge and Light-off with Immediate Flame Drop-out

· Metal yoke for coil missing.

· Coil wire #2 and #8 reversed.

· Low resistance of coil holding circuit, terminals #1 and #2,

(

1350 ohms ± 10%

)

Burner Locks Out After Trial For Ignition

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