Tankless water heaters build up debris and calcium on its filter and inside the machine. So it’s essential to flush the whole water heater with food-grade like white vinegar at least once every 12 to 18 months. At this simple maintenance time, it is best to clean the air filter inside the tankless water heater when you are going to flush your water heater. As an expert, we must say that this simple maintenance must improve the efficiency and lifetime of your tankless water heater. Here we provide instructions that will show clearly how to flush a tankless water heater? We took a Takagi tankless water heater to make the steps more comfortable. But we assure you that these instruction steps can be applied to any tankless water heater as you can locate the corresponding components on your water heater.
Let’s Follow The Steps To Clean Your Water heater
- Step 1: Gather Your Flushing Materials
To complete this task, you’re going to need:
- Five-gallon bucket.
- Two stainless steel washing machine hoses.
- A submersible pump.
- Four gallons of white food-grade vinegar. (You can easily buy white food-grade vinegar at any grocery store.)
Note: You can purchase all these materials from Amazon. Click to check the price: Tankless-Water-Heater-Cleaning-Kit.
- Step 2: Locate the Shutoff Valves
In this step, you have to find out the color-coded handles underneath your tankless water heater. These levers shut off the water and gas supply to your tankless water heater. If you see the levers are in line with the pipe, that means it’s ON, and if it’s vertical, that means it’s off. Now carefully turn them all vertical to the pipes. In that way, you can shut off the gas (A yellow handle attached on the right side to the water heater silver pipes, Central handle color is yellow, the cold blue one shows water intake, and the red one is hot water outflow pipes. Before following this step instruction, please unplug your unit from the wall socket.
- Step 3: Unscrew Cold Water Service Valve
In this step, you have to unscrew the cold water service valve. You can find the service valve just above the red and blue levers. Now you have to turn the levers vertically to the pipe and shut off the water from your tankless water heater. But before opening the service valve, you have to read your materials first.
Precaution Note: An external pump is attached to the wall near your floor. Its electronic components are exposed through the vents at the top of the device. So you need to avoid getting any water on this device to reduce the short circuit or an unexpected accident. At the same time, be careful about burning yourself during you open hot water pipes. So do your washing process slowly.
- Step 4: Setup Your Vinegar and Pump
In this step, empty your 5-gallon bucket of any water you collected from the service valves by following steps 3.
Now fill your empty bucket with 4 gallons of food-grade white vinegar and then attach the hose, which goes into the cold water service valve into the top of the sump pump. But make sure all connections are connected tightly and don’t plug in the pump yet.
Now you can place the pump into the vinegar before plugging it into the wall. The most important thing is that there’s no On or Off switch, so it will instantly turn on when you plug it into the wall socket. Again, make sure the hose goes appropriately into the hot water service valve attached safely before plugging the sump pump into the power outlet, and the other end of the sump pump is placed into the bucket. That doesn’t need to screw into the pump; just loosely put it into the vinegar bucket. Now you saw the hoses attached and the pump submerged in the vinegar. That means you’re ready to begin the flushing of your tankless water heater.
- Step 5: Start Circulating vinegar to clean water service valve.
In this step, you can plug the pump into the power outlet. It circulates the vinegar through the cold water service valve whose color is blue and out vinegar through the hot water service valve whose color is red and recycled into the same vinegar bucket. You have to leave the whole process for at least 60 to 90 minutes. The manual manufacturer says go the process for 45 minutes, but we figured it’s been better to go longer to 60 to 90 minutes.
- Step 6: Cleaning the Air Intake Filter
When your vinegar is circulating, you can also clean out the air intake filter. Because if there’s an error message on your display that reads “027, “then you need to clean the air intake filter.
You find the air intake filter located inside the tankless water heater. Don’t worry; it’s not hard to open; first remove the tankless water heater faceplate. It held together with four screws, two on top and two on the bottom of the water heater body. After finding the air intake filter, at first, the very first moment, unscrew all the screws, then lift upwards to unlock the top of the faceplate from the top of the tankless water heater frame. This process exposes the inside of the tankless water heater.
In the following steps, you have to locate the single screw holding the air intake filter in place. Then first pull slightly towards, then slide the whole thing to the left and angle it slightly to slide over the motor without doing any damage. Then I just turned the water spout and turned it on full blast and rinsed the heck out of the filter. Then used paper towels to dry it as best as possible and reinstalled the filter the same way you took it out.
Then replace your tankless water heater faceplate and let the pump continue to run for 60-90 minutes. During this process, please don’t plug your tankless water heater into the outlet until the flush procedure.
- Step 7: Rinse the tankless water heater after the vinegar treatment
After completing the 60 to 90 minutes vinegar circulation through the pump, you’re ready to rinse the vinegar out from the tankless water heater. In the following process, you have to unplug the pump from the wall outlet and lift out the sump pump. Then allow it to drain into the vinegar bucket and place it aside from your space. Now put the empty bucket under your tankless water heater. Then unscrew the hose from the cold water blue side only. After that, replace the service valve cap and screw it. Then leave a hot water hose. The following process opens the lever that controls the cold water inflow and passes the water about 4 to 5 gallons through your tankless water heater.
Now open the output of the hot water hose into the bucket. But make sure to close the cold water valve. When that is complete now, you need to check the water filters. To find out is there any water exit or not. If there is water, unscrew with your finger and redirect them to your tankless water heater hose pipe on the blue side. After that, remove the filters make sure to inspect the debris. Thoroughly rinse filters with water and screw them again.
- Final Step: Reattach everything and Turn on your water heater.
After completing step number seven, your tankless water heater and its air intake filter have been cleaned; now it’s time to reassemble the whole water heater. After reassembly, please make sure to screw all service caps tightly before opening the valves.
When you are sure that everything is perfectly capped tightly, you can start opening valves. Better to start the cold water valve first. After starting a cold water heater valve, you will hear water rushing on your system. Next substep is to open the hot water valve. Then the gas and central circulation valve, whose color is yellow. Finally, you are allowed to plug in your tankless water heater. See carefully, on display to specific icons on the screen. If your power display shows everything right, the cleaning process is completed, and you can use your water heater anytime.
There are many websites like homeguides.sfgate.com or others to research how to flush tankless water heaters? We hope that our research tankless water heater flushing steps help you to clean your tankless water heater to give the best performance like a new one. I hope our research is enough to do your job because these steps are suitable for cleaning almost any tankless water heater to better perform like a new one.