Bradford White Water Heater M1TW40S6FBN

Verify 120VAC and proper polarity at wall outlet.

With unit plugged in and control power switch in the “ON” position, verify LED status.

Using a volt meter set to volts AC, is there 120VAC across terminals shown in photo 29?

Is there 120VAC across terminals shown in photo 30?

Is there 120VAC across black & white wires as shown in photo 32?

Check for 120VAC between black & white wires.

Verify error code as listed on page 13.

Blower Temperature Switch Testing

WARNING — 120 volt potential exposure. Use caution to avoid personal injury

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

Remove the three screws from control access cover on blower and remove cover.

Locate blower temperature switch.

Switch setting: opens on rise at approximately 165°F, auto resets on fall at approximately 130°F.

Disconnect wire leads to switch.

Using a multi-meter set to the ohms setting, is there continuity between the switch terminals?

Cast Iron Burner Air Shutter Adjustment

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

Adjust air shutter for proper burning

Is the flame blue with a minimum of yellow tips?

Is the burner operation noisy or is there soot formation?

Close inner door and observe burner operation

Does the burner operate as adjusted in step 2?

Repeat air shutter adjustment if necessary

Refer to 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.

Refer to page 25 to obtain water temperature.

Are thermal well resistance values correct?

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

Turn off gas supply to water heater.

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

Disconnect pilot tube (7/16 wrench) and feedline (¾ wrench) from gas control.

Disconnect igniter/flame sensor wire from gas control.

Remove burner assembly from combustion chamber.

Thoroughly inspect burner surface area and burner port area and remove any loose debris.

For cast iron burners, inspect for any debris build up inside burner casting.