Navien Error Code E351: Abnormal Auto Feeder Valve
How to Fix Navien Code E351
- Step 1: Check the system pressure gauge on your Navien boiler. It should typically be between 12-15 PSI when the system is cold.
- Step 2: If the pressure is significantly below 12 PSI, try manually adding water to the system using the manual fill valve (refer to your Navien manual for its location). Slowly open the valve until the pressure reaches the desired range, then close it tightly.
- Step 3: Inspect your radiators and accessible piping for any signs of leaks (water stains, drips). If you find any leaks, try to contain them and call a qualified technician immediately.
- Step 4: If the pressure drops again quickly after adding water, or if you are uncomfortable performing these steps, contact a qualified HVAC technician to diagnose and repair the problem.
What Does Navien Error Code E351 Mean?
The E351 error code on your Navien boiler indicates an issue with the automatic water feeder valve. This valve is responsible for maintaining the correct water pressure inside your boiler system. When the system pressure drops (due to leaks or usage), the auto feeder valve opens to add more water and keep the system running smoothly. If the system detects an abnormal operation of this valve, it will display the E351 error and potentially shut down to prevent damage. This error is important because low water pressure can cause the boiler to overheat, operate inefficiently, or even damage components. It's like trying to run your car with low oil – eventually, something will break. Addressing this issue promptly will help ensure your heating system operates safely and reliably.
Common Causes of Navien Code E351
- Faulty auto feeder valve: The valve itself may be defective and not opening or closing properly.
- Low water pressure in the supply line: If the incoming water pressure to the boiler is too low, the auto feeder valve may struggle to maintain the correct system pressure.
- Leaks in the heating system: A leak somewhere in your radiators, pipes, or boiler components can cause a continuous drop in pressure, forcing the auto feeder valve to work overtime and eventually trigger the error.
- Air in the system: Air pockets can interfere with pressure readings and the operation of the auto feeder valve.
Applicable Navien Models
Source Documentation
This error code is documented in 3 official Navien technical manuals.
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