The Impact of Hard Water on Tankless Water Heaters and How to Mitigate It

Tankless water heaters are known for their efficiency and endless hot water. Unlike traditional tanks, they heat water only when needed, saving energy and money. But even the best systems need routine care to stay in top shape.

One hidden threat to their performance? Hard water. Minerals in your tap build up within your unit. This reduces its efficiency and causes damage. Without proper maintenance, your heater may struggle, costing you more in repairs and energy bills.

Want to keep your tankless water heater running like new? Let’s explore how hard water affects it and what you can do to prevent problems.

How Hard Water Affects Tankless Water Heaters

Hard water is one of the most notorious culprits of appliance malfunctions and inefficiencies in any home. Ignore this and these are the problems your unit may suffer from.

Mineral Buildup Restricts Water Flow

When hard water runs through your heater, minerals slowly collect inside. Over time, this buildup forms scale deposits, which narrow the pipes. When this happens, water struggles to flow, making your heater work harder. This extra strain can lead to overheating and costly breakdowns.

Reduces Heating Efficiency

A tankless water heater works by heating water as it passes through. But when mineral deposits coat the heating elements, they act as an insulating layer. This forces the unit to use more energy to heat your water, increasing your utility bills.

Shortens the Lifespan of Your System

The more strain your heater experiences, the faster it wears out. A unit that should last 20 years may fail much sooner if hard water is left unchecked. Repairs will become more frequent, and eventually, you may need a full replacement.

Increases Maintenance Needs

Occasional flushing is required for tankless heaters. But hard water makes maintenance even more critical. Without regular descaling, the buildup can become severe. Ignoring this maintenance need for too long can only worsen your unit’s condition. In the end, you may only have to do more regular tankless water heater repairs moving forward.

How to Protect Your Tankless Water Heater from Hard Water

The good news is that hard water damage can be prevented. With the right steps, you can keep your heater working efficiently for years. Here’s what you can do to achieve these results.

Install a Water Softener

The best way to prevent mineral buildup is to treat the water before it enters your heater. A water softener removes calcium and magnesium, replacing them with sodium or potassium. This stops scale from forming and keeps your system running smoothly.

Use a Scale Inhibitor

If a water softener isn’t an option, a scale inhibitor can help. These systems use chemicals or filters to prevent minerals from sticking to your pipes and heating elements. They won’t remove the hardness, but they will reduce scaling.

Flush Your Heater Regularly

Flushing your tankless water heater removes any buildup before it becomes a problem. Experts recommend doing this at least once a year, but in areas with very hard water, you may need to do it more often.

Here’s how a plumber flushes your system:

1. Turns off power and gas – This ensures safe maintenance. A plumber shuts off electricity and gas to prevent accidents. This step is crucial before opening any part of the system.
2. Closes the water supply valves – Stops new water from entering. The plumber shuts the inlet valve to isolate the heater. This prevents water from diluting the cleaning solution during flushing.
3. Connects hoses to the flush ports – Allows cleaning solution to flow through. Hoses are attached to both hot and cold water ports. This setup lets the cleaning solution circulate and break down the scale.
4. Pumps descaling solution through the system – This breaks down and removes mineral deposits. The plumber uses a pump to push the solution through the heater. It dissolves built-up minerals that restrict water flow.
5. Flushes with clean water – Clears out any remaining solution. After descaling, fresh water is pumped through to rinse the heater. This ensures no chemicals are left behind in the system.
6. Restores power and water supply – The system is now ready to use again. The plumber turns everything back on and checks for proper function. Your heater should now run more efficiently and heat water faster.

This process helps maintain efficiency and extends the life of your heater.

Use a Pre-Filter for Sediment

In addition to minerals, hard water often contains tiny particles like sand or rust. These can clog small openings in your heater. A sediment filter removes these particles before they reach your system, preventing damage.

Keep Your Tankless Water Heater in Optimal Condition with Formula Plumbing Services

Hard water can be tough on a tankless water heater, but you can always prevent it from taking over. By taking these steps, you can keep your heater running efficiently for years. Pair that with dependable maintenance from a trusted plumber, and you can fully enjoy your hot showers without unexpected breakdowns.

Formula Plumbing Services is your go-to expert for water heater care. We offer fast, fail-proof installations, reliable repairs, and comprehensive system diagnostics. Our flexible maintenance plans ensure your heater stays in top condition year-round.

Step up your tankless water heater maintenance—book us now!