Version 2.21
148 NPE Service Manual
8.1.4 Cleaning the Inlet Water Filter and
Recirculation Inlet Filter
To clean the filters:
1. Drain the water heater.
2. While the filters are removed, rinse it with clean running water
(cold) and, if necessary, scrub it clean with a brush.
Cold Water
Inlet Filter
Recirculation
Inlet Filter
3. Reinsert and tighten the filters.
4. Refill the water heater.
8.1.5 Cleaning the Air Intake Filter
If the air intake filter becomes clogged by dust or lint, the water
heater will cease to operate and “Error Code 10” will appear on
the front panel display. To properly maintain the water heater, you
should clean the air intake filter every 3-4 months.
To clean the air intake filter:
1. Press the Power button on the front panel to turn off the water
heater.
2. Disconnect the power supply to the water heater.
3. Remove the front cover of the water heater.
4. Remove the screw that secures the air intake filter (the filter is
located at the top left of the water heater).