I ran into a problem last week. My kitchen drain clogged up. I first tried an acid based drain cleaner, then boiling water. It didn't clear and was very slow. I then tried a lye based drain cleaner. Again it didn't clear. My wife suggested a plunger. I dtried that and it stopped up completely. I then used a fish tape (a device used in the telecom industry to snake through conduit so as to pull cables through walls). It wouldn't go around the 90 degree turns and so I fished from the clean outs of the pipe, in a straight line to the end of the pipe. That didn't work. I rented a plumber's snake and ran it down the pipe. That didn't work either. I was scratching my head about what to try next.
My son, Eric, was assisting me while I pushed the snake. He turned the crank. He came up with the idea that cleared the clog. We took a garden hose and connected it to the hot water spigot of my basement washing machine hook up. I turned on the hot water and ran it into the sump-hole until it was good and hot. I then turned off the hot water and shoved the hose into the pipe, throught the clean-out, and when it reached the final bend where the pipe makes 170 degree bend into the main drain pipe, I turned on the hot water. This blew the cog completely out of the pipe and into the septic tanks.
It turned out that grease was the culprit. My basement is faily cool and as grease from normal dishwashing travelled down the pipe, it solidified at the far end, at the final elbow, until it formed the clog. Boiling water didn't work because it cooled on the 30 foot run to the elbow and didn't have sufficient heat to melt the clog.
So, in retrospect, before cleaning a pan that was used to fry foods in, especially if the fat was solid to begin with (lard, shortening, butter, etc.) get as much of that out of the pan before it goes into the soapy water. And use a strong emulsifying agent, such as Dawn dishwashing soap. And use as water as hot as you can stand.
My problem stemmed from not wanting to use dishwashing liquid on my cast iron. My pans are well seasoned and work beautifully. But the plumbing problem brought everything to a standstill in my kitchen for about 3 days.
Heat is your freind. Grease is the enemy.
Seeeeeeya; Goodweed of the North