Home Maintenance: 101 - Flushing Tankless Water Heaters

Things that almost all home owners forget or dread doing …. Home Owner Maintenance

If you haven’t noticed yet, water conditions around the Greater Houston area are not always ideal. Most typically, water can be found to have excess amounts of calcium , sediment, mineral deposits causing the water to be classified as Hard Water. This causes scaling, corrosion or calcium build-up on all plumbing components & fixtures.

This is why it’s so crucial to regularly perform maintenance on your water heating equipment. (Both Tankless or Regular Tank Units)

You can always hire a Professional Local Plumbing Company - Brick Plumbing to perform these tasks if you do not feel comfortable or are short on time.

The whole process takes roughly 30 mins - 1.5 Hours.

Things needed for this procedure…

1. Recirculation Pump (submersible pump) (Can be picked up for about $50-75 at local hardware store), you will keep this for future flushings.

2. 5 Gallon Bucket

3. A set or standard Washer & Dryer connection Hoses (2) $17

4. Cleaning Solution, We Recommend This one from Haymaker $20

5. Personal Protection Equipment (Gloves, safety goggles, mask if needed…)

Once you have collected these items, you can begin!

Step 1: It’s always best practice to shut the supply valves off just incase the drain valves are faulty. Almost all plumbing valves are 1/4 turn meaning if the handle is parallel with the pipe it’s open or ON, if you turn the handle perpendicular with the pipe it is OFF. So close the two handles located as number 1 in the picture above.

Step 2: Once the supply valves are closed, unscrew the drain port covers at number 2. Take the two washing machine hoses and connect the ends to the now open ports (make sure the gasket / washer is present in the end of the hose for a tight seal). Then take the hose attached to the cold / blue side and attach to the top of the pump. Add approx. 1 gallon of fresh water to the bucket, then add the entire bottle of descaler / cleaning solution to the bucket. (Recommend wearing gloves throughout whole process) Then place the pump into the bucket along with the hose connected to hot / red side.

Step 3: Next up is to open the Red & Blue valve handles labeled number 3. Plug in / Turn on the pump and once water starts flowing through the Red discharge hose you can then set a 20 Minute timer & allow the cleaning solution time to work.

Step 4: Once the timer is finished, you can shut off the pump, close the Blue valve handle. Unhook the hose from the pump & Blue / Cold side of the water heater. The re-install the drain port cap for this side. Once it finishes draining, you will then want to discharge the remaining liquids in the bucket in a safe manner. (Your clear liquid you started with will likely resemble the picture below)

We now need to flush the system with clean water, as to remove any chance of the cleaner going into the home’s plumbing lines.

Step 5: Place the open end of the Red hose back into the bucket. Slowly open the Cold water inlet valve handle (Right side Number 1) and allow water to flow through the Red hose into the bucket. You will want to let it fill up about 75% of the way and shut off the valve so you can dump the bucket. Repeat this process approx. 3-5 times.

Step 6: Once the previous step is finished, make sure the Cold water supply handle you were just using is closed. Then after the Red hose drains, shut the Red handle (Left side Number 3). Remove the Red hose & reinstall the drain port cap / cover. Once both caps are back in place & both Number 3 Valves are closed, you can finally open the Left or Hot supply valve back to the on position, then the right or Cold valve.

Seems like a lot of steps / work right ?! Well it only needs to be performed once a year and it is crucial in how well your system works & how long your system will last. The process is much simpler than it reads and is definitely easier after the first time!