How to Install a Garbage Disposal

Learn how to install a garbage disposal in this Howcast plumbing repair video with expert Tim Flynn.

"I’m Tim Flynn and I’m the owner of Winters Plumbing and Heating in Cambridge, Massachusetts. Winters Company offers plumbing, heating, cooling. If you need service today; we’re the business to call. My website is wintershomeservices.com. I’ll be talking to you today about plumbing.

Installing a garbage disposal is generally a very easy task to take on. I think the biggest thing you have to watch out for is the.. a lot of times people have dishwashers, and dishwashers do discharge into the side of the disposal. We get a lot of people that call in, say, you know, we replaced the new disposal but now my dishwasher doesn’t drain, and that’s because the side of the disposal, where the dishwasher discharges into has a knock-out plug within it, that most people don’t take out. So I think that’s probably one of the biggest challenges I’ve seen.

Putting in a disposal itself is a matter of disconnecting some electricity, so if you have the wherewithal to disconnect electricity and shut it off, there’s a challenge there. If you have the wherewithal to disconnect a couple of plumbing slip nuts, there’s going to be at least one connection, then the final connection is to the sink, and the the disposal could come down fairly easily.

People may get in over their head trying to replace a disposal. So, especially around the electricity, I tend to go to the side of caution and not advise doing something like that.

Disposals are sold by horsepower, quarter-horse, third horse, and half horsepower. The half horsepower, at the top of the scale, is made for someone who does a lot of cooking, and uses the sink as a trashcan, and really just drops a lot of stuff down. You usually see a lot of half-horse powers like, people that cook every day. The mid-range people, they use it infrequently to a lot, you could probably get away with a third-horse power. But the quarter-horse ones, the smaller ones, are basically bachelors, for those who don’t do a lot of cooking, just disposing whatever he has to."