Our household plumbing is an area where ignorance too often seems to be bliss.

We take the valuable and labor-saving equipment in our homes for granted, guilelessly believe the silly things people tell us about its use, and thoughtlessly do things that impede the efficiency of its operation and even cause expensive damage. Here are a few facts to undercut some of the most common “myths”:

1. You can put anything down the disposal. Don’t do it—at least not if you want it to work properly. Coffee grounds, grease, leftover foods like rice, pasta and fruit peels (they swell up); flushable cat litter, cotton balls and buds, flushable wipes, diapers, sanitary products (ditto); condoms (can block drain); paint, cleaning products (corrosive); and medications (pollute the water supply)—all these are no-nos.

2. Running water while running the disposal makes it run better. No, it won’t. It causes those foods named above to bloat. And it won’t help if the disposal drain is already blocked.

3. Lemon peel in the disposal will kill odors. See above—and your disposal may not be strong enough to chop up lemon peel.

4. Ice cubes will sharpen disposal blades. No, it won’t, but it will clean them. So will eggshells.

5. Liquid drain cleaner will clean up anything that goes down. No, it won’t, at least not anything solid.

6. There’s no point in repairing a simple leaky faucet. Yes, there is. You’re paying for the water, for one thing, so over time you’re wasting a lot of money. In water shortage areas, like ours, you’re making a bad problem worse. And, in hard water areas like ours, the dripping can corrode your fixture, another unnecessary expense.

7. Putting water and soap on bathroom or kitchen fixtures keeps them clean. Well, maybe, but it also causes corrosion, peeling and bubbling of the fixtures’ surfaces. Wipe them off.