How to Stop a Water Hammer

CLANK! THUD! BANG! If these are the sounds that greet you every time you turn off a faucet, then your plumbing has a water hammer. And it’s a real problem.

What is a Water Hammer?

Imagine running as fast as you can, and suddenly a wall drops in front of you. SLAM! That’s basically what’s happening inside your plumbing when you shut off a faucet. When high-pressure water in the line is brought to a halt, it can make an alarming clamor. The water’s velocity may also cause the pipe to rattle against boards, adding more unnecessary noise.

Water hammers can happen anytime you turn off a faucet, or when a washing machine or dishwasher automatically closes a valve. This is more than an audible nuisance. If left untreated, the thudding and banging can loosen joints and connections in the pipes. Leaks are the inevitable result.

Check the Water Pressure

Buy a water pressure gauge at any hardware store and attach it to a faucet. The water pressure shouldn’t exceed 45 pounds-per-square inch. If you get a high reading, try adjusting the regulator at the incoming main water line. The pressure regulator is a brass, bell-shaped device. With a simple turn of a screw, you can adjust the pressure anywhere from 25 to 75 psi.

If that doesn’t work, have a plumber install a water hammer.

How a Water Hammer Arrestor Works

A water hammer arrestor is a device that cushions the blow by directing the hydraulic shock upward into an air-filled chamber. It’s consists of a coupling and a 4-inch vertical chamber. The device can be positioned any which way, so fitting it between wood frames usually isn’t a problem.

It’s not a DIY job. A plumber will first drain down your system and solder water hammer arresters onto both the cold and hot water supply lines near the offending faucet. Soldering copper pipes isn’t something that an amateur should attempt. The installation also may involve cutting out some drywall. Leave this job to the professionals.

For all of your plumbing needs, turn to your friendly neighborhood plumbers at Plumb Doctor. Call (770) 293-7080 to schedule an appointment.