Navien Water Heater NFB-301C

Unfasten the latches to remove the front cover

Remove the screws on the internal air filter

Remove the filter from the boiler

Remove dust and debris from the filter

Note any issues related to dust and debris accumulation

Inspect interior; clean and vacuum if necessary

Clean condensate trap and fill with fresh water

Verify flue and air lines in good condition and sealed tight

Check system water pressure/system piping/expansion tank

Place a bucket under the boiler to collect the residual water inside the boiler.

Disconnect the power cord to turn off the boiler.

Close the water supply valve and the return valves on the manifold system.

Remove the drain valve on the manifold system to drain the boiler.

Ensure the pump does not become wet during the process.

Check the condition and attachment of the ground wire to the boiler casing

Measure ground continuity using a continuity meter

Is the ground continuity satisfactory?

Replace ground wires if ground continuity is not satisfactory

Visually inspect the vent piping for signs of leakage

Check the vent piping for signs of blockage

Visually inspect the burner flames

Condensate Trap and PVC Fittings Inspection

Inspect the condensate trap for any issues

Inspect the PVC fittings for any signs of wear or damage