"Airing Out" your pipes
By Samantha Mazzotta

Q: When flushing the toilets, the pipes in the house make a banging noise for about 20 seconds. The noise stops when we run water from the faucets in the bathroom or kitchen. What is the cure? -- Rosemarie G., via e-mail

A:The banging noise you're hearing, also known as "water hammer," is a result of air being trapped somewhere in the plumbing system - - most likely in the cold-water supply lines, since you're able to stop the noise by turning on faucets. A home's pipes have lots of bends and turns and odd short stems that lead nowhere. This is not just so the pipes will get where they need to go; certain parts are deliberately placed in certain configurations to redirect air bubbles so they don't impede water flow or cause annoying problems like water hammer. Even with this preventive planning, air can still get trapped in spots where it isn't supposed to be. This can occur after work is done on the plumbing, such as repairing or replacing pipes, faucets or other hardware. It can also occur due to high water pressure in the pipes, which can happen when the home's supply system is not designed to compensate for municipal supply feeds that might be delivered at high pressure. You can attempt to "bleed" air out of the supply pipes first. Turn off the main water supply to the house. Locate the lowest faucet in the pipe system (the first-floor bathroom, or an outdoor spigot); then locate the highest faucet in the system (such as an upstairs bathroom). Open the lowest and highest faucets and allow all the water to drip out. When the dripping stops,

close both faucets. Turn on the main water supply. Test the system by flushing the toilets a few times. If this does not work, contact a plumber to inspect the water supply lines and

measure the

water pressure. He or she may recommend installing a pressure-reducing valve at the main supply feed, or a water-hammer reduction valve.

HOME TIP:

To loosen a stubborn shower head so it can be cleaned or replaced, squirt a few drops of penetrating oil (3-in-1 or WD40, for example) around the threads, and allow it to set for 24 hours.

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