Bradford White Water Heater M4TW50T6FBN

Burner Inspection and Air Shutter Adjustment

Check for potential causes of unstable pilot flame

Inspect pilot flame for stability

Inspect main burner for smooth ignition and blue flame with minimal yellow tips

Ensure main burner is free from debris accumulation

Gas Control & Thermal Well Removal From Water Heater

Position gas valve power switch to the “OFF” position and unplug heater from power supply.

Drain heater to a point below the gas control level.

Turn off gas supply to water heater and disconnect gas piping from gas control.

Disconnect wire harnesses and burner assembly from gas control.

Remove gas control & thermal well by rotating flats of Thermal Well counter clockwise (1-5/16" wrench).

Gas Control Removal From Thermal Well

Position gas control power switch to the “OFF” position and unplug water heater from power supply.

Turn off gas supply to water heater and disconnect gas piping from gas control.

Position gas control power switch to the “OFF” position.

Unplug blower power cord from wall outlet.

Disconnect vent system from exhaust adapter on top of blower.

Remove exhaust adapter from blower using a blade screwdriver and retain for use on new blower.

Remove the three blower mounting screws using a ¼" nut driver.

Remove blower with gasket from water heater.

Cast Iron Burner Air Shutter Adjustment

Ensure safety precautions are taken to prevent personal injury due to hot components.

Remove outer jacket door and slide inner door from left to right to open.

Loosen the air shutter nut and adjust the air shutter to achieve a blue flame with minimal yellow tips.

Tighten the air shutter nut after adjustment.

Is the flame lifting off the burner ports or creating noisy operation?

Close inner door and observe burner operation.

Does the burner operate as adjusted with the inner door closed?

See pages 29 & 30 for gas control input & output testing.

Position gas valve power switch to the “OFF” position and disconnect thermal well harness from gas control.

Determine the resistance of thermal well sensors 1 & 2 using a multi-meter set to the Ohms setting.

Insert one meter probe into center wire position of thermal well connector, insert the second probe into either of the outside wire positions.

Alternate the probe on the outside position to the opposite outside wire position.

See page 25 to obtain water temperature.

Are thermal well resistance values correct?