A once-a-year plumbing checkup: what to look at so small problems stay small

The yearly list in one paragraph

Once a year, flush the water heater and check its temperature setting, relief valve and drain pan; test the main shutoff and the valves under every sink and toilet; do a water meter test and a toilet dye test for hidden leaks; look under sinks and at washing machine and toilet supply lines; pay attention to slow drains and have the main line scoped in an older home with repeated clogs; prepare outdoor faucets and irrigation for winter; and test your water hardness. That covers most of what turns into an expensive call when it is ignored.

None of it requires special tools, and most of it takes a weekend morning. I would rather you catch a weeping valve or a sediment-heavy tank on your own schedule than meet it as a flooded closet on a holiday.

Pick a date and keep it. It helps to tie it to something you already do every year, such as changing smoke detector batteries in the fall, which also happens to be the right season to get ready for freezing weather. Keep a simple note of what you checked, what you found and what was fixed, along with the age and model of the water heater. That record is useful the next time something goes wrong, and it is worth having when you sell the house and a buyer's inspector starts asking questions.

Water heater: flush, temperature and the parts around it

Sediment settles at the bottom of a tank water heater over time. It makes the heater work harder, causes rumbling and popping, and contributes to an early failure. Draining a few gallons from the valve at the bottom, or flushing the tank fully, once a year slows that buildup. If the drain valve is old and stiff, be gentle; a valve that will not close again is its own small emergency.

Check the temperature while you are there. The U.S. Consumer Product Safety Commission urges households to set water heaters to 120 degrees Fahrenheit, which reduces the risk of scald injuries and saves energy. Look at the drain pan under an attic or closet heater and make sure its drain line is clear, look for rust or moisture around the base and connections, and on a gas heater, make sure nothing is stored close to it.

A tankless heater needs a different routine: periodic descaling of the heat exchanger and cleaning of the inlet screen, according to the manufacturer's schedule. My guide comparing tankless and tank water heaters covers how the upkeep differs.

Every shutoff valve should actually shut off

Valves sit untouched for years, and then the one day you need them, they will not turn or they leak when they do. Once a year, turn each one off and back on: the valves under every sink, behind every toilet, at the washing machine and at the water heater. If one is stiff, drips at the stem or will not stop the flow completely, have it replaced. It is a small job now and a big one in an emergency.

Test the main shutoff too. The City of Dallas Water Utilities notes that the private shutoff valve is often near an outside faucet close to the house, may be near the irrigation valves in homes with in-ground sprinklers, and in older homes may be buried with a small L-shaped handle. Make sure everyone in the house knows where it is and how to close it.

If the house sits empty for stretches, or you simply want a backstop, consider a smart shutoff valve. Installed on the main line, it watches the flow of water and closes the supply automatically when it senses a leak, and many models alert your phone. It does not replace the yearly check, but it limits the damage when something fails between checks.

Two ten-minute leak tests

Hidden leaks are the ones that cost the most, because they run for months. The U.S. Environmental Protection Agency's WaterSense program estimates that household leaks waste more than 9,300 gallons in the average home every year. Two simple tests catch most of them.

• Meter test: turn off all water use, note the meter reading, wait two hours without using water and check again; any change means a leak
• Leak indicator: with everything off, a spinning triangle or wheel on the meter means water is flowing somewhere
• Toilet dye test: put a few drops of food coloring in each tank; color in the bowl within ten minutes means the flapper is leaking
• Winter baseline: WaterSense suggests comparing your use in a cold month, when there is no irrigation, against the rest of the year

Under the sinks and behind the appliances

With a flashlight, look under every sink for drips, water stains, swollen cabinet floors or a musty smell. Check the supply hoses on the washing machine, the toilets, the dishwasher and the refrigerator ice maker. Rubber hoses that are cracked, bulging or stiff should be replaced, and braided supply lines that show rust or fraying at the ends are worth replacing too. A failed washing machine hose can release a lot of water quickly.

Look at the base of each toilet for movement or staining on the floor, and at the caulk around tubs and showers. These are small fixes that keep water out of subfloors and walls. If a leak turns out to be more than a fitting, a licensed plumber can locate it with equipment instead of opening walls to search.

Drains and the main sewer line

Keep strainers in kitchen sinks and showers, clean bathtub stoppers of hair, and pay attention to which drains are slow. A single slow drain is usually a simple clog, and my guide on clearing a clogged drain yourself covers what works. Several slow drains, gurgling toilets or a clog that keeps returning point to the main line.

In an older house, especially one with original cast iron under the slab, a camera inspection of the main line every few years, or after repeated clogs, is money well spent. It shows corrosion, roots and low spots before they become a backup. My guide on what a failing cast iron sewer line means explains what the camera looks for. Also find your outdoor cleanout, usually a capped pipe near the foundation, and keep it clear of mulch and plants so it can be reached.

Outdoor faucets and irrigation before winter

Fall is the time to get the outside of the house ready. The city's winter guidance recommends draining and removing garden hoses, covering outdoor faucets with hard foam covers or cloth, wrapping exposed pipes outside and in unheated areas including the attic, and making sure an automatic sprinkler system has the rain and freeze sensor the City of Dallas requires.

In spring, turn the outdoor faucets on and watch for drips inside the wall or at the foundation, which can mean a pipe split over the winter. Run each irrigation zone and look for broken heads and soggy spots. My guide on keeping pipes from freezing in a winter storm has the full freeze routine.

Hard water and what is in your glass

Mineral content in water shows up as white scale on faucets and showerheads, spotty glasses and a heater that seems to lose efficiency. It also shortens the life of water heaters, tankless units and fixture valves. A hard water test once a year tells you whether scale is a real issue in your house and whether it is changing.

If it is, there are options. A water softener addresses hardness. Filtration addresses taste and contaminants: an activated carbon filter or a reverse osmosis system can remove substances such as chlorine. The right choice depends on what the test shows and what bothers you, scale, taste or both. A plumber who tests first and then recommends is more useful than one who leads with a product.

A softener or filter needs its own yearly attention once it is installed. Softeners need salt and an occasional check that they are regenerating as they should, and filter cartridges and reverse osmosis membranes have replacement schedules set by the manufacturer. An overdue filter does not just stop working; it can restrict flow and make the system seem broken.

Signs that mean call now, not next year

Some findings should not wait for the next yearly check. If you smell gas, leave the house and call the gas company from outside. For the plumbing items on this list, call a plumber if you find any of these.

• Water leaking from the water heater tank itself
• A meter that moves with everything in the house turned off
• A warm spot on the floor or the sound of running water when nothing is on
• Sewage smell, or water backing up into a tub or shower
• A main shutoff valve that will not close

Letting us handle the checkup

If you would rather not do this yourself, our Home Guard membership covers the core of it: a yearly safety inspection of all your plumbing, a water heater flush and a hard water test, along with priority service and discount pricing on repairs (replacements excluded). The same membership includes spring and fall heating and cooling inspections for members who want both done by one company.

When the technician finds something, you get an explanation and a job price before any work begins, and nothing is done until you approve it. We serve homes across Dallas, the Park Cities and the northern suburbs, we call ahead to confirm the arrival time, and our work is guaranteed.

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