Applies to:
Replacing the Transformers
Both the Express Filter transformer and the control transformer are the same part number. These components drop the line voltage to low voltage components such as, control board, Express Filter board and contactors.
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To avoid electrical shock or property damage, move the power switch to OFF and disconnect power. |
Checkout
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Hinge-down the control panel to access the desired transformer.
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Pull the appropriate white connector, either from the Express Filter PC board or from the control PC board.
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With the power on, take a voltage reading on the appropriate pins, using the chart and drawing below. If transformer proves faulty, continue with replacement instructions.
Test Points | Results |
---|---|
From pin 1 to 2 | 24 VAC |
From pin 4 to 5 | 240 VAC |
From pin 3 to 5 | 208 VAC |
Replacing
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Disconnect power and using a 5/16 inch socket, remove the nuts securing the transformer and pull the transformer from unit.
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Replace transformer in reverse order.
Related Content
Replacing the High Temperature Limit Control
Replacing the Temperature Probe
Replacing the Gas Control Valves
Replacing the Air Pressure Switches
Replacing the Ignitor and Flame Sensor Assembly
Replacing the Ignition Modules
Replacing the Pressure Transducer
Replacing the Main Power Switch
Reference