A.O. Smith GPVL-50 ProLine XE 50 Gal 38,000 BTU ProLine XE Power Vent Gas Water Heater 4 Flashes Error Fix: Temperature Exceeded High Limit

Error code 4 Flashes on the A.O. Smith GPVL-50 ProLine XE 50 Gal 38,000 BTU ProLine XE Power Vent Gas Water Heater means: Temperature Exceeded High Limit. The water temperature has exceeded the high limit safety threshold. The ECO (Energy Cut Off) switch has tripped to prevent scalding or tank damage. This can be caused by a defective thermostat that fails to shut off the gas burner, sediment buildup insulating the tank bottom causing localized overheating, or a malfunctioning gas valve. Let the water cool, then press the reset button on the ECO switch (located on the gas valve). If it trips again, the gas control valve or thermostat may need replacement.

The most successful fix is "Replace the Thermostat or Gas Control Valve to Fix High Temperature Limit Trips" (hard difficulty, ~90 minutes). Estimated DIY cost: $50-$100. HomeMD has 2 community-ranked fixes for this error.

This error is rated high severity. You should address it promptly — continued use could cause damage or safety concerns.

Yes — the top-ranked community fix ("Replace the Thermostat or Gas Control Valve to Fix High Temperature Limit Trips") is rated hard difficulty and takes about 90 minutes. Tools needed: T20 Torx screwdriver, Multimeter, Pipe wrench, Wire labels.

DIY cost: $50-$100. Professional repair typically costs $250-$400. Many homeowners save money by trying the top-ranked community fix first.

The A.O. Smith GPVL-50 ProLine XE 50 Gal 38,000 BTU ProLine XE Power Vent Gas Water Heater has 5 other known error codes, including: 1 Flash (Normal Operation), 2 Flashes (Thermopile Voltage Low), 5 Flashes (Temperature Sensor Failure), 7 Flashes (Gas Control Valve Failure), 8 Flashes (Loss of Pilot Signal).

Error code 4 Flashes also appears on 3 other A.O. Smith models: GCR-40 ProLine 40 Gal 38,000 BTU ProLine Gas Water Heater with Energy Saver, GNVR-50 ProMax Gas 50 Gal 40,000 BTU ProMax Gas Water Heater with Electronic Ignition, GPVT-50 Power Vent 50 Gal 38,000 BTU Power Vent Gas Water Heater with Electronic Ignition. The fix may vary by model, so check each model's specific page for tailored repair steps.