Plumbing Troubleshooting
Plumbing trouble shows up as a symptom long before it shows up as a flood: a drain that takes a little longer each week, a knock in the wall when the washer stops, a brown ring on the ceiling. Most symptoms have two or three usual causes, and a few checks will tell you which one you’re facing and whether it can wait.
Narrow It Down by Symptom
The first thing to settle is how far the problem reaches. One fixture acting up points to that fixture or the pipe under it; several at once point farther along, to the main drain or the supply line.
Symptom Check
Choose a symptom, then press the button.
Three Checks Worth Making First
The Water Meter Test
Turn off every faucet and appliance that uses water, then look at the water meter. Most meters have a small triangle or star-shaped dial that turns whenever water moves. If it turns with everything off, water is going somewhere; close the small valves behind the toilets and look again, and if the dial stops, a toilet is the leak.
The Dye Test for a Running Toilet
Put a few drops of food coloring in the tank and don’t flush for about 15 minutes. Color in the bowl means the flapper is letting water past, the most common reason a toilet runs on its own.
One Drain or Several
One slow drain is almost always a clog near that fixture: hair in a tub, grease in a kitchen line. Several slow drains at once, or water rising in the lowest drain when a toilet upstairs is flushed, point to the main line, a job for drain cleaning or a look at the sewer line.
What That Noise in the Pipes Means
A plumbing system makes noise for a reason, and the sound usually says where to look.
| Sound | Likely cause | Urgency |
|---|---|---|
| Banging when a faucet or the washer shuts off | Water hammer: water stopping fast with nothing to cushion it, loose pipe straps, or high pressure | Soon. Repeated hammer shakes joints loose; check the pressure first. |
| Whistling or squealing | A worn washer or cartridge in a faucet, a tired toilet fill valve, or a valve left partly open | Low, unless the toilet also keeps running. |
| Gurgling in a drain | Air pulled through a trap by a partial clog farther down or a blocked vent | Moderate; high when several drains gurgle together or the lowest one backs up. |
| Popping or rumbling in the water heater | Hard-water scale on the tank bottom, with water trapped under it boiling | Moderate. Have the water heater looked at; sooner if it leaks or the water runs rusty. |
| Dripping inside a wall or ceiling | A leaking supply or drain line, or in summer, condensation on a cold-water pipe | High. Run the meter test, and shut the main if the dial moves with everything off. |
| Humming | High pressure vibrating a valve or pipe, or a pump running: a sump, well or recirculating pump | Low to moderate, but a sump pump that hums without moving water needs fixing before the next heavy rain. |
| Running water when nothing is on | Most often a toilet flapper; also a hidden leak, a dripping outside spigot, or a water softener running its cycle | Find out soon: dye-test each toilet, then do the meter test. |
Where Do-It-Yourself Should Stop
A careful homeowner can clean an aerator, swap a flapper or clear a sink trap. These four jobs are different, because a mistake costs far more than the repair:
- Gas lines and gas connections. A joint that’s slightly off can leak slowly for weeks, and every gas connection has to be leak-tested before the appliance runs again; mistakes here end in fires and carbon monoxide, not puddles.
- The main sewer line. Opening a cleanout on a backed-up main lets everything standing in the pipes out at once, often onto the basement floor, and a rented drum machine can punch through old clay or cast iron and turn a clog into a sewer line repair.
- Water heater relief valves. The temperature and pressure relief valve keeps a tank from bursting; one that drips may be doing its job because the pressure or heat is too high, and capping or swapping it without finding out why removes the last safeguard.
- A main shutoff that won’t turn. Forcing a seized gate valve can snap its stem and leave a leak at the one valve that controls the house.
Pressure Gauges and Hard-Water Scale
Two things decide how water behaves at the tap: the pressure it arrives at and the minerals it carries. Lancaster County’s water is hard, heavy with calcium and magnesium, and those minerals settle out as scale in aerators, shower heads, faucet cartridges and water heaters.
A faucet that loses flow over a few months and wears a white crust on its aerator is telling you about scale, not the pipes. Pressure is the other half: too little makes a weak shower, too much wears out valves and sets off water hammer.
What water pressure should a house have?
Most homes run between about 40 and 80 psi, and many plumbers like to see 50 to 60. Plumbing codes call for a pressure-reducing valve when the supply runs above 80 psi, because pressure that high wears out valves, supply lines and fill valves early.
How can I check the pressure myself?
Hardware stores sell a gauge that threads onto an outdoor spigot or the washer hookup. Read it with nothing else running, then again at another time of day, since street pressure changes from morning to evening.
Why has my water pressure dropped over the years?
Galvanized steel pipe closes up from the inside with rust and scale, a little more every year. A worn pressure-reducing valve, a main valve left partly closed, or aerators packed with scale do the same thing faster. One weak faucet starts with its aerator; a whole house that runs weak calls for a look at the supply lines.
Is hard water hurting my plumbing?
Slowly. Scale shortens the life of tank water heaters and clogs tankless heat exchangers, faucet cartridges and toilet fill valves, which start to drip or run. Soaking aerators and shower heads in white vinegar clears the worst of it, and flushing a tank heater once a year keeps the sediment down.
Bring What You Found to the Call
Before you call, write down which fixture it is, what it sounds or looks like, when it started and what the checks showed. Good notes make the first conversation short and point straight at the right part of the house.