Photo of a mineral-coated bathroom shower headHow to Detect Hard Water - by visual inspection - Water Softener Guide

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Hard water or high mineral content water supply: how to recognize that you need a water softener by simple visual inspection of fixtures in the building . Here is a description of what to look for and where to find it in diagnosing hard water conditions.

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Easy Ways for a Homeowner, Tenant, or Inspector to Detect Hard Water

Photo of a stained bathtubHard water is not just an aesthetic concern in the shower. Very hard water can clog pipes [photo of scale build-up in a water pipe] and water heating equipment (especially tankless coils such as the ones we show here) leading to costly repairs.

Hard water is not normally health concern people although the treatment of hard water using a conventional ion-exchange (salt) water softener can, especially if improperly adjusted, place salt (NaCl) into the water supply at a level which people on low-salt or no-salt diets may wish to avoid.

We discuss this point further

Separately at WATER TESTING GUIDE we describe easy tests you can make to actually measure the hardness of the building water supply.

Here are some visual clues that the water supply at a building is hard

There is a water softener installed - look for the water softener treatment tank and salt tank, usually installed close to where water enters the building or close to the water pressure tank and pump controls if a private well is in use.

Hot water pressure is noticeably less than cold water pressure in the building.

Since minerals precipitate out of hard water faster when the water is heated, we expect hot water piping to clog with minerals faster than cold water piping.

Photo of tankless coils used to heat domestic hot waterSigns of tankless coil clogging from hard water: When a tankless coil is installed, since that's where our water is the hottest, often the tankless coil clogs before other plumbing materials.

Look for evidence of previous acid-cleanout of the tankless coil. If the coil has been cleaned before, you'll see extra drain valves and shutoff valves installed on the hot and cold water lines close to the tankless coil.

The plumber uses these valves and drains to first isolate the tankless coil from the rest of the building water supply piping, and second, to pump an acid through the coil to try an dissolve the mineral clogging therein.

Once a tankless coil (or "hot water coil") has been acid-cleaned it may re-clog faster than before, since the surface of the copper tubing has been etched by the copper and may be more receptive to mineral deposition.

A pile of tankless coils found in a home, such as we show in the photo in this section, is a likely sign that they have been replaced repeatedly - the water in this home is probably quite hard.

Photo of mineral clogging of a faucet strainer

Mineral deposits on faucets and faucet strainers are an easy-to-spot sign of hard water at a building.

Often faucets and fixtures can be cleaned successfully using special cleaners to dissolve mineral deposits, or sometimes simply by soaking the parts in a vinegar solution.

Our photo at left looks up into the mouth of a bathroom faucet spout, showing minerals deposited by three years of exposure to hard well water.

Photo of a mineral-coated bathroom shower head

Mineral deposits also appear on shower heads
 and are unmistakable.

Our photo of a shower head shown just left shows white and tan minerals deposited by three years of exposure to hard well water.

Photo of a stained bathtub

Stained plumbing fixtures such as the bath tub shown in this photo often tell a lot about the history of a building as well as the condition of its water supply.

When hard water is supplied to a building the deposition of thin mineral deposits on bath tub and shower surfaces forms a rough coating that in turn increases the rate at which soap scum and dirt adhere.

Hard Water Lime Deposits in Other Problem Locations

White lime deposits have been reported on roofs where leaky swamp coolers were installed - WHITE STAINS on ROOFS or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.


Continue reading at WATER HARDNESS: HOW TO MEASURE or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.


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