How to Maintain a Tankless Water Heater
- 1). Turn off the water heater.
- 2). Turn off the incoming and outgoing water valves by turning the handles clockwise.
- 3). Fill a bucket or basin tub with a gallon of white vinegar.
- 4). Connect a short length of garden hose to the outgoing water valve. Place the tub of vinegar under the hose and valves.
- 5). Connect a garden hose to the incoming water valve. Connect the other end of the hose to a water pump.
- 6). Place the submersible water pump into the tub of vinegar.
- 7). Open the outgoing/incoming water valves, and turn on the water pump. The pump will begin to flush vinegar through the tank. Let the tank flush for 15 to 30 minutes. After you've finished flushing vinegar through the tank, flush some clean water through it for a few minutes to clean out all of the vinegar.
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