Water Heater Service Manuals & Error Codes

Service manuals, error codes, and parts diagrams for water heater repair across all major brands.

324Manuals

162Error Codes

13Brands

MyPros+ Max

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Step-by-step tests with expected resistance, voltage, and continuity values
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M+

M+ Max·Whirlpool Water Heater

My appliance shows an error code

M+

Control board fault diagnosis

From Tech Sheet W10810403, p.8:

1.Access the service diagnostic mode using the tech sheet procedure. Record all stored fault codes from the error history, not just the most recent active code.

2.Measure control board supply voltage at the test points. Expected: 12 VDC and 5 VDC. A drop below 4.75 VDC on the logic rail points to a failed onboard regulator.

3.Inspect all connectors on the main control board for corrosion, thermal stress, or backed-out pins. Reseat each connector with the power disconnected.

Part WPW10804018

Electronic control board

Top Error Codes for Water Heater Repair

CodeBrandDescription

A7BoschOutlet temperature sensor not sensing expected output temperature...E9BoschOverheat sensor (ECO) open circuit (resets when cooler temperatures...EABoschNo flame ionization detected with water flow.ECBoschGas leakage error, gas valve circuit not closing properly.0Bradford WhiteNo electrical power to the gas control; control LED is not on or...0 FlashesHoneywellControl is off or pilot is out.031A.O. SmithIncorrect dipswitch settings on the computer board.05RheemAir intake or vent exhaust opening may be blocked.1A.O. SmithCommunication error between the upper (electronic control display)...1 flashBradford WhiteGas Control V1: Pilot flame is detected and gas control is powered,...1 FlashHoneywellNormal operation (bright/dim heartbeat).1 flash (V1)Bradford WhitePilot flame is detected and gas control is powered, waiting for...1 flash every 4 sec (green)Bradford WhiteGas Control V2: Not an error; indicates pilot is lit and main burner...1 flash every 4 sec (WR Electronic)Bradford WhiteWhite Rodgers Electronic: Not an error; indicates pilot is lit and...1 flash every 4 sec green (V2)Bradford WhiteNot an error; indicates pilot is lit and main burner is off. Turn...

Show all 13 brands

A.O. Smith American Water Heater Aquastar Bosch Bradford White Electrolux Hatco Kenmore Maytag Reliance Rheem Rinnai State

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Access 324 service manuals, 162 error codes, and step-by-step diagnostics for water heater repair.