A.O. Smith Water Heater Blinking 4 Times
Four flashes on an A.O. Smith gas water heater means High-Temperature Shutdown. Here’s the reset procedure and when it means a real problem.
Water Heater Blinking Light: What It Means
A blinking or flashing status light means something different on every water heater brand. Find your brand and flash count below.
Rheem ProTerra Alert Codes (A/T Series)
Rheem ProTerra heat pump water heaters use A- and T-prefix alert codes — not the generic E1/E2/E3 codes some sites list. Here’s the real pattern.
Rheem Tankless Error Code 29 (Condensate/Neutralizer)
Rheem tankless code 29 points to the condensate drainage or neutralizer system. Here’s what to check before calling for service.
Rheem Tankless Error Codes
Every Rheem tankless water heater error code, what it means, and the safe first steps before calling a technician.
Navien Error Code E016 (Overheat)
Navien E016 means the unit’s overheat protection tripped. Scale buildup and restricted flow are the usual suspects — here’s the order to check.
Navien Error Code E515 (PCB Error)
Navien E515 points to a control board (PCB) fault, often tied to grounding or a power surge. Here’s what to check before calling a tech.
Navien Error Code E012 (Flame Loss)
Navien E012 means the burner lit, then lost its flame signal mid-cycle. Here’s the diagnosis order, from gas pressure to the flame rod.
Navien Error Code E110 (Air Pressure / Exhaust Blockage)
Navien E110 means the unit detected abnormal air pressure or an exhaust blockage and shut down safely. Check the filter, vents, and drain.
Navien Error Code E003 (Ignition Failure)
Navien E003 means ignition failure: the unit couldn’t safely light or detect a burner flame. Check gas supply and the flame rod first.