Dishwashers and garbage disposals
Mike Frentz has covered the home fixes for toilets, bathroom and kitchen sinks, and shower fixtures. In rooms with plumbing in your home, that pretty much leaves three things: the hot water heater; the dishwasher; and the garbage disposal.
Where replacing a washer in a traditional faucet might be considered Plumbing 101, Mike says that by comparison, replacing the hot water heater is graduate level work.
But Mike says installing that hot water heater is one of two things: a lot of work for an amateur, and probably a job for a plumber.
As far as the other two appliances go:
You probably didn’t know all built-in dishwashers are the same size – about 2 feet wide and 2 feet deep. This is good news for people replacing a dishwasher, because most of your work is already done for you.
If you’re installing a built-in dishwasher for the first time, Mike recommends a plumber. “You’re going to need someone to run a water line, a drain line and a power supply. It’s not that these things are really difficult, but you have to know what you’re doing.”
Then again, if you’re replacing a dishwasher, all those lines already are in place. So Mike says the biggest job you’ve got is getting the old dishwasher out from under the counter without hurting the countertop and surrounding cabinetry.
“You’re going to want to disconnect the water line, the drain line and the power supply before you slide the old dishwasher out,” Mike says.
Shut off the water valve – there’s only one, because your dishwasher only uses hot water.
Disconnect the drain hose. It runs from the dishwasher to the disposal and is attached to the disposal with a clamp.
Turn off the electrical – Mike says be safe and shut off the circuit breakers and then disconnect the circuit lines. The circuit breaker panel is in the basement. The rest of the electrical system is behind the kick plate, located at the bottom front of the dishwasher. You’ll have to get down on the floor, with a flashlight, to see the electrical box. “Disconnect everything and you’re done,” Mike says.
Now slide the old dishwasher out and slide the new one in. Reconnect the water, the drain line and then the power lines. When reconnecting the power, black wires match black connections, white matches white, and a bare or green wire is the ground. This is standardized according to the National Electric Code, so you don’t accidentally attach wire A to screw B and end up in hospital emergency room C with no eyebrows.
“I also really recommend people take a look at redoing the water line as long as they’ve got everything disassembled,” Mike says. “The old ones were hooked up with a larger size half-inch copper tubing. The new ones take a connecting hose that’s flexible.”
This new dishwasher connector hose is wrapped in a flexible stainless steel sheath, which makes it more durable if you have to run it around a corner that might eventually wear down a regular rubber hose. It also comes with a 90-degree fitting – properly called a 3/8" MIP (male iron pipe) X 3/8" compression ell.
“Every dishwasher made has to have this fitting,” Mike says. “And dishwashers now come with their own drain hose made of corrugated flexible vinyl, which connects to the garbage disposal. And all garbage disposals have to accept that hose.
“The reason is that’s the hose that carries the soft food and debris from the dishwasher to the garbage disposal.”
Here’s the thing to remember. It’s the last step, but it’s the first thing you need to know.
Once you’ve properly seated the new garbage disposal, it will not line up with the existing pipe. It just won’t. It’s a universal truth.
So when you remove the old garbage disposal, Mike recommends removing the pipe it was attached to, right to the wall, and bringing it in to Frentz and Sons. Not only can they match it up, but Mike will suggest replacing it with a plastic pipe. “The advantage is it’s inexpensive, no corrosion with plastic, and you’re not trying to match up an old pipe with a new fitting, which can be very frustrating,” he says.
Garbage disposals today can be installed with tools you always have with you – your hands. “It’s universally an almost tool-less installation. The garbage disposal attaches to the bottom of the sink.
“If you look at the instructions, you’ll see everything tightens, clockwise, with sometimes as little as a quarter turn. The mounting assembly is on top (directly underneath the sink drain), and that attaches to the mounting ring, and the motor attaches to that. Other than replacing the pipe, that’s it.
A word of caution: Make sure the drain line has a trap in it. It's shaped like a U The water settles in the base of the “U” and forms a seal that keeps sewer gases from backing up through the drain and into your house. “Some people try to get around this by using a straight pipe, which can’t form a seal. That’s just dangerous for them and their family,” Mike says.
What horsepower garbage disposal do you need? Mike says it depends on how you’re going to use it
Most homes really only need a 1/3 or 1/2 horsepower unit. The more expensive disposals have more sound insulation to help keep down the noise. The larger disposals (3/4 and 1 HP) might be for people running a catering business or a small restaurant.
“If you can’t bring in the pipe that connects the disposal, take a Polaroid or digital picture and bring it in. Some of our customers shoot it with a video camera and bring that in