Testing Water Hardness Before You Buy a Generator

Why water hardness matters for a steam generator

A steam generator boils water to make the steam that fills your shower or steam room. Everything dissolved in that water stays behind when the water turns to vapor. Calcium and magnesium, the two minerals that make water hard, deposit as scale on the heating elements and inside the tank.

Steam generator makers are direct about this. Amerec's FAQ notes that hard water has negative effects on the generator and recommends a whole house water treatment system if water quality is a concern. The same page warns that tanks need flushing monthly, or more often depending on local water conditions, when the unit lacks an auto drain.

Scale does two kinds of damage. It insulates the heating elements, so the generator works longer to produce the same amount of steam. It also narrows the water inlet and steam outlet passages. Over time the unit produces weaker steam, runs hotter, and wears out sooner. A descaling routine becomes part of upkeep.

Method one: read your municipal water quality report

If you are connected to a city or town water supply, your utility publishes a Consumer Confidence Report, usually once a year. It lists the mineral content of the water it delivers, including hardness expressed as calcium carbonate. This is the cheapest and fastest way to learn your hardness class, and it costs nothing.

Find the row that says hardness, total hardness, or calcium carbonate. The number is usually given in milligrams per liter, which is the same as parts per million. If the report gives hardness only as a range across the year, use the upper end of that range for planning, because seasonal changes can push mineral content higher.

One caveat: the report describes water at the treatment plant, not water at your tap. Minerals can be added by aging pipes between the plant and your home. For that reason, treat the report as a good first estimate and confirm it with a test strip if your reading lands near a boundary between hardness classes.

Method two: measure your tap water with a test strip

A water hardness test strip is a small paper strip coated with a color-changing reagent. You dip it in a glass of cold tap water for a moment, wait the time printed on the package, and compare the strip color to the chart on the bottle. The chart maps colors to hardness levels, usually labeled soft, moderately hard, hard, and very hard.

Test strips are sold at hardware stores and online. They are inexpensive, and one bottle covers dozens of tests, so you can test water from different taps in the same house. Wells, in particular, can vary from one property to the next, so a strip test is the right method if your water comes from a private well rather than a utility.

For accuracy, run the test on cold water that has run for a minute or two. Hot water from a tank has already concentrated minerals and will read higher than your actual supply. Also test at the same tap where you plan to connect the generator, since an in-line filter or softener will change the reading.

If you want more precision than a strip provides, a liquid reagent kit gives a drop-count result. It costs a little more and takes a few extra minutes, but the number it returns is fine enough for choosing a water treatment strategy.

What your reading means for generator choice

Once you have a hardness number, you can plan around it. Low-mineral water needs little more than the standard maintenance routine. High-mineral water calls for a treatment step before the generator, because scale inside the tank is not something you can reverse once it forms.

Amerec's guidance points to two responses. One is a whole house water treatment system, which protects every fixture and appliance, not just the generator. The other is an auto drain option that flushes the tank after each steam bath. MrSteam's AutoFlush works on the same principle, automatically flushing sediment about two hours after every steam session.

A softer middle option is a point-of-use scale-reducing filter, installed on the cold water line feeding the generator. These filters use ion exchange resin to swap hardness minerals for sodium or potassium, and they are sized for a single appliance rather than a whole house.

Maintenance that protects any generator

The generator makers agree on the basics of upkeep. Amerec says the tank should be flushed monthly, or more often depending on local water conditions, when the unit does not have an auto drain. The same page instructs owners to inspect for water leaks, check wiring for signs of overheating, and tighten all connections whenever the generator is opened. A regular descaling routine extends the life of the unit.

MrSteam takes the opposite approach with AutoFlush: the system cleans itself two hours after each bath, removing sediment before it has time to harden into scale. That is worth factoring into your buying decision because it removes the human step from the maintenance routine.

A generator with an auto drain or flush feature costs more up front, but it directly answers the condition that causes most premature generator failures. If your test strip shows hard water and you would rather not commit to a monthly flush reminder, a self-flushing model is the lower-risk choice.

Test before you buy, not after

The best time to learn your hardness number is before you choose a generator, because the reading shapes both the generator model and the water treatment plan. A five-minute strip test at the kitchen sink saves you from installing a generator that will choke on scale within its first year. If you are shopping for a complete setup, see our roundup of steam generators.

Your decision tree looks like this. If the report or strip says soft water, a standard generator with a monthly flush is adequate. If it says hard water, add an auto drain model or a scale-reducing filter, and preferably both. If it says very hard water, treat the water before it reaches the generator and keep a descaling schedule on the calendar.

Wells complicate the picture because groundwater hardness changes with rainfall and season. Test the well at two different times of year before you settle on a treatment strategy. For city water, the annual utility report plus a single strip test is enough to make the call.

Finally, this is a decision about installation, not just the generator itself, so share your hardness reading with your plumber or installer. They can confirm that the treatment equipment fits the space, that the supply line is routed correctly, and that the generator can be serviced without moving furniture or cabinetry.

What to pick for your use

Questions

How do I find my water hardness number?

Read your municipal water quality report, which lists total hardness as calcium carbonate. Or dip a test strip in a glass of cold tap water and compare the color to the chart on the bottle.

What does a water hardness test strip measure?

It measures the concentration of calcium and magnesium dissolved in the water, shown as a color that you match to a chart labeled soft, moderately hard, hard, or very hard.

Can I install a steam generator with hard water?

Yes, but you need to plan for scale. Amerec recommends a water treatment system for hard water, and its FAQ warns that tanks need more frequent flushing when water conditions are poor. An auto drain option reduces the burden.

How often should I flush a steam generator tank?

Amerec recommends flushing monthly, or more often depending on local water conditions, when the generator does not have an auto drain. MrSteam's AutoFlush automates the job by flushing sediment about two hours after each steam bath. See our descaling routine guide for details.

What is the difference between a water softener and a scale filter for a steam generator?

A softener treats the whole house and removes hardness minerals from every tap. A point-of-use scale filter installs on the cold water line to the generator only and reduces scale inside that single appliance.

Is hot water from the tap a good sample for a hardness test?

No. Hot water from a storage tank has already concentrated minerals and will read higher than your actual supply. Always test cold water that has run for a minute or two.