How To Flush A Navien Tankless Water Heater

Alright, gather 'round, friends! Let's talk about something truly riveting: flushing your Navien tankless water heater. Now, I know what you’re thinking: "Flushing? Sounds like something I do after questionable sushi." But trust me, this is crucial for keeping your hot water flowing and avoiding a chilly shower surprise. Think of it as giving your water heater a spa day. A spa day involving vinegar and pumps, but a spa day nonetheless.

Why bother flushing it anyway? Well, hard water is a real menace. It's like the clingy ex of the plumbing world, leaving mineral deposits (mostly calcium and magnesium – the same stuff that builds strong bones, ironically) all over the inside of your water heater. These deposits, also known as scale, can reduce efficiency, increase energy bills (nobody wants that!), and even lead to catastrophic failure. And by catastrophic, I mean a cold shower and a hefty repair bill. So, let's avoid plumbing Armageddon, shall we?

What You'll Need: The Flushing Arsenal

Before we dive in, let’s assemble the tools of the trade. You’ll need:

• A submersible pump: This little guy is the workhorse of the operation. Don't skimp – get one that can handle hot water. Unless you enjoy the smell of melted plastic.
• Two hoses: Typically, washing machine hoses work great. Make sure they're long enough to reach from your water heater to a bucket (more on that bucket later).
• A bucket: A five-gallon bucket is ideal. You'll be surprised how much gunk comes out. Prepare to be disgusted.
• White vinegar: The magic elixir! Don't even think about using anything else. It's cheap, effective, and environmentally friendly. Plus, your garage will smell like pickles, which is a bonus in my book. You'll need several gallons, depending on your system's size.
• A wrench or pliers: For loosening and tightening connections.
• Eye protection: Safety first, people! You don't want vinegar splashing into your eyeballs. Trust me on this one.
• Gloves: Because nobody likes vinegary hands.
• A timer or your phone: Because who actually keeps track of time anymore?

Fun Fact: Did you know that hard water can also make your hair dull and your skin itchy? So, by flushing your water heater, you're basically giving yourself a free beauty treatment. Okay, maybe not free, but definitely cheaper than Botox.

The Step-by-Step Flushing Fiesta

Alright, now for the main event. Follow these steps carefully, and you'll be a tankless water heater flushing pro in no time. Or at least, you won't break anything. Probably.

Step 1: Power Down and Cool Off

First things first, turn off the power to your water heater at the breaker. Safety, remember? Then, turn off the gas supply valve to the unit, usually a yellow handle near the unit itself. Let the water heater cool down for a bit. We don't want any scalding surprises. It's like trying to hug a porcupine – best to let it calm down first.

Step 2: Isolate the Water Heater

Next, you need to isolate your water heater from the rest of your plumbing system. Find the cold water inlet valve and the hot water outlet valve on your unit (usually they're clearly marked in blue and red, respectively.) Close both of these valves. This prevents the vinegary goodness from contaminating your entire house’s water supply. Imagine brushing your teeth with vinegar – yuck!

Step 3: Connect the Hoses

Now, grab your trusty hoses. Connect one hose to the cold water inlet (the blue one) and the other to the hot water outlet (the red one). The ends of the hose that aren't connected to the unit, should go in the bucket. Make sure the hoses are securely connected to prevent leaks. Leaks mean wasted vinegar, and nobody wants that!

Important Tip: Before connecting the hoses, open the drain valve on the bottom of the unit (if it has one) and let any remaining water drain out. This will help speed up the flushing process.

Step 4: The Vinegar Bath

Place the submersible pump inside the bucket. Fill the bucket with several gallons of white vinegar. Submerge the pump completely, making sure the inlet is fully submerged. This is where the magic happens. The pump will circulate the vinegar through the water heater, dissolving those pesky mineral deposits.

Step 5: Circulation Time

Plug in the submersible pump. The vinegar should now be circulating through the water heater. Let it run for at least one hour. For heavily scaled units, you can let it run for up to three hours. The longer, the better. This is a good time to catch up on your favorite show, bake a pie, or finally learn how to knit. Just don't forget about the vinegar!

Pro-Tip: Every 30 minutes or so, reverse the flow of the vinegar by switching the hoses on the inlet and outlet valves. This helps to dislodge deposits from both directions.

Step 6: The Great Flush

After the vinegar has done its work, it’s time to flush the system with clean water. Disconnect the pump. Remove the hose from the cold water inlet (blue one). Let that hose drain into a safe drain or another large bucket. Open the cold water inlet valve and let fresh water run through the system until the water coming out runs clear. This can take a while, so be patient. You're basically giving your water heater a vinegar detox. And it’s probably feeling much better!

After that, disconnect the hose from the hot water outlet (red one), and put it where you drained the other hose. Now, open the hot water outlet valve. Again, let the water run until it is completely clear. Then, close both valves.

Step 7: Reconnect and Restart

Now that the system is clean, it's time to put everything back together. Disconnect the hoses and reconnect the cold and hot water lines as they were originally. Open the cold and hot water inlet valves. Turn the gas supply back on. Finally, turn the power back on at the breaker. Cross your fingers and hope for the best!

Warning: There might be some air in the lines, so expect some sputtering and gurgling when you first turn on the hot water. This is normal. Just let it run for a few minutes until the air is purged.

Step 8: Check for Leaks

Carefully inspect all the connections for leaks. If you find any, tighten the fittings or replace the hoses if necessary. A small leak can turn into a big problem, so don't ignore it.

Congratulations! You've Flushed Your Navien Tankless Water Heater!

Pat yourself on the back. You've successfully flushed your tankless water heater. Now you can enjoy long, hot showers without worrying about mineral buildup or unexpected cold-water surprises. How often should you do this? Well, it depends on your water hardness. If you have really hard water, you might need to flush it every year. If your water is relatively soft, you can probably get away with every two years. Keep in mind, you should always follow the manufacturer's instructions.

So, there you have it. Flushing your Navien tankless water heater isn't exactly a party, but it's a necessary evil. And who knows, maybe you'll even find it strangely satisfying. Just remember to wear your eye protection, and don't drink the vinegar! Happy flushing!