Descaling a Tankless Water Heater
Tankless water heaters are an amazing upgrade for your home. They are energy-efficient, space-saving, and built to last longer than your typical tank water heater. Just like any major appliance, they need some TLC to keep working their best. One of the most important maintenance tasks? Descaling.
Let’s dive into why descaling matters, how often you should do it, signs your system might need attention, and whether you should DIY or call in a pro.
What is Descaling?
Descaling a water heater is the process of removing mineral buildup – mainly calcium and lime – that accumulates inside the tank or heating elements over time, especially in areas with hard water (Cincinnati is one of these areas!) This buildup can reduce your water heater’s efficiency, shorten its lifespan, and lead to inconsistent water temperatures.
Descaling involves flushing the tank with a descaler solution that dissolves the deposits and restore optimal performance. Regular water heater maintenance like this not only helps keep your unit running smoothly, but can also save you money on energy bills and costly repairs down the line.
Why Do Tankless Water Heaters Need Descaled?
Unlike traditional tank water heaters that hold hot water in a tank, tankless units heat water on demand. As water flows through the system, minerals can build up inside the heat exchanger, especially if you have hard water.
Over time, this scale build-up acts like insulation on the heating element; this makes your unit work harder, reduces its efficiency, shortens its lifespan, and even causes damage if left unchecked. Given that the Greater Cincinnati area typically struggles with hard water, you can expect your tankless water heater to require regular descaling maintenance.
How Often Should You Descale a Tankless Water Heater?
Most manufacturers recommend to descale a tankless water heater once a year. However, if you have especially hard water or a larger household that uses a lot of hot water, you might need to do it every 6 – 9 months.
If you’ve installed a water softener, you may be able to extend the time between cleanings. However, it is always recommended to check your tankless water heater at least once a year to ensure maintenance is not required.
Does My Tankless Water Heater Need Descaling?
How do you know when your tankless water heater needs to be descaled? Some tell-tale signs include:
1. Fluctuating water temperature
2. Odd noises that come from your unit while it’s running
3. Reduced water pressure coming from your hot taps.
4. It may take longer time than normal for your water to heat when the tap is running.
If you notice an error code on your tankless water heater, check your manual first to see what the error code means; in some cases, it may signal the need for descaling.
Can You DIY Descale Tankless Water Heaters?
To descale tankless water heaters DIY, you will need a tankless water heater flush kit and a tankless water heater descaler. A tankless water heater flush kit will usually include a submersible pump, two hoses, and a 3 – 5 gallon bucket. Flush kits and descalers can both be found online or at your local home improvement store.
To descale a tankless water heater:
1. Start by turning off the power or gas to the unit and shutting off the cold and hot water valves.
2. Connect the two hoses to the valves. Typically, the cold line hose is then connected to the submersible pump in the bucket, and the hot line hose leads back into the bucket to create a loop.
3. Fill the bucket with your tankless water heater descaler.
4. Plug in the pump and let it circulate the solution through the system for 45 minutes to an hour. This dissolves the mineral buildup inside the heat exchanger.
5. Dump the solution, refill the bucket with clean water, and run the pump for 10–15 minutes to flush out any remaining residue.
You can then remove the hoses from the valves and get your water heater back up and running!
Note: ALWAYS check your tankless water heater’s manual before attempting to perform maintenance on it. Each unit is different and improper handling may void your warranty or damage the unit.
Why It’s Better to Call a Pro
While you can DIY descaling a tankless water heater, it can create bigger problems if not done correctly; incorrect hose setup, over-tightening or damaging of valves, or not rinsing the descaler solution properly can lead to needing expensive repairs or, worse yet, needing to replace the unit entirely. Letting the professionals handle your descaling saves you from having to clean a mess and saves you time!
Professional-grade water heater descaler works more efficiently than an at-home or “over-the-counter” solution found in stores. Contractors use descalers that are stronger than what the average DIY-er is qualified to use, can include corrosion inhibitors to protect metal components, and are designed to work faster and dissolve mineral buildup more effectively.
Contractors will also inspect other components of your tankless water heater while they perform the maintenance, like sensors and filters, to make sure all parts of your unit are running smoothly. They can also catch early signs of wear or malfunction before they become big, expensive issues that are harder to resolve.
Other Maintenance Your Tankless Water Heater Needs
Descaling isn’t the only thing you should do to keep your tankless water heater in tip-top condition. Here’s a quick list of other maintenance items to keep your system running smoothly:
1. Clean the in-line water filter. This tiny filter traps debris before it can get inside your heater. Rinse it every few months.
2. Check the air intake filter (if your unit has one.) Dust and debris can restrict airflow. Clean or replace as needed.
3. Inspect the venting system to make sure there are no blockages or leaks.
4. Flush the system. Besides descaling, flushing removes general sediment and buildup.
Are you in the Cincinnati area and need your tankless water heater serviced? You’re in luck! At Quality Comfort Home Services, we offer tankless water heater maintenance that keeps your system working good as new. Whether you need to descale or you think it’s time for a routine check-up, our plumbing pros are here to help! Contact us and let us put your water heater worries to rest.
