Adding a tankless water heater to your home is a great idea that saves you money on both electricity and water. But did you know that they require special maintenance? If you neglect this maintenance, you will void your heater’s warranty which could be expensive if there’s ever a problem.
These water heaters build up calcium and magnesium deposits on the inside of the device. They can also accumulate rust and sediment. Eliminating all these accumulations on a regular basis can help your tankless water heater work better and longer.
Scale Buildup Will Require More Energy to Heat Water
When calcium and magnesium build up on your plumbing fixtures, this mineral deposit is called scale. When this crust of scale gets too thick, the water heater simply won’t work well anymore. That’s because scale acts as an insulator, keeping the heat source from contacting the water. This means more energy will be required to heat the water to the desired temperature. It’s also possible that your flow of hot water will begin to dwindle.
Even worse, if you wait too long and there’s a heavy buildup of scale, it may not even be possible to clean out the water heater.
How to Eliminate Scale from Your Tankless Water Heater
First, choose a memorable date for your annual maintenance, like your birthday or New Year’s Day. Then follow this procedure:
- Look at the owner’s manual to see if the power needs to be shut off. If it’s electric, you’ll need to shut off the power at the breaker panel. If it’s gas-powered you’ll need to rotate the gas cutoff until all fuel is cut off.
- Turn off the valves that control the water supply to the heater and that control the release of water.
- For the next step, you’ll need a large bottle (over a gallon) of white vinegar, hoses and a sump pump. Place the pump in a large (five gallon) bucket and attach the hoses to the water heater and the pump.
- Pour the vinegar into the bucket and start the pump. The vinegar solution will flow into the water heater and back into the bucket.
- Let the pump flow for at least 45 minutes.
- Turn off the pump and disconnect the hoses. Pour the vinegar back into the bottle and dispose of it. You might notice that the water is a light blue-green from whatever copper oxidation existed in the water heater.
- Rinse the bucket and pour two gallons of fresh water into it. Reattach the hoses to the heater and the pump and run the pump. This step washes out the vinegar which could corrode the metal parts inside the heater if it’s left in contact with them.
- After a few minutes, turn off the pump and disconnect the hoses.
- Open both valves.
- Turn the power or gas supply back on.
What to Do After Descaling Is Complete
Vinegar is a weak acid that dissolves scale. But because it’s corrosive, you should also wash the pump and the hoses very well before putting them away. Once the hoses are washed, drain the water out of them and hang them for a while to ensure all water is removed.
Let the sump pump dry out well before putting it away.
You’re now done with your tankless water heater flush until next year!
A Warning for Households with Very Hard Water
If your community has very hard water, you would be smart to install a water-softening system to remove calcium, magnesium and other minerals. You will protect the longevity of all your water-using appliances, including water heater, dishwasher, washing machine and refrigerator ice maker. Your dishes and clothes will look cleaner and your skin and hair will feel softer. Your plumbing fixtures will not develop crusty yellow or blue scum on them.
If you need to flush a tankless water heater but don’t want to do it yourself, give us a call. We can provide a tankless water heater if you don’t have one, flush one that’s working or repair or replace one that’s not. We’re available 24 hours a day at (505) 243-1227.