RE: COEX cellular core PVC schedule 40, non pressure
I've been pouring a gallon or so of boiling macaroni water down the kitchen drain a couple of times every week. A friend recently told me to stop since the hot water could damage my drainpipe. No probs yet after 4 years, but was he right?

when in doubt, seek manufacturer advice. it's easy these days on the wacky wacky webbipoo. http://plasticpipe.org/pdf/tn-...tic_non_pressure.pdf is the standard by the plastic pipe industry. they list maximum continuous flow temperature, nonpressure, for plain PVC pipe as 150 degrees. for CPVC pipe, 210. for ABS and PB, 210 degrees.

note if you go to the originator of plastic pipe, Genova, their website says it meets NSF requirements. the National Sanitation Federation requires smoothness to avoid hiding particles of food or offal, and sanitizing temperatures for cleaning (180 plus.) so it's probably fine.

if you have enough length in some of that drainage, and nobody has washed off the code markings with gasoline or goof-off, you can easily tell if it's PVC or CPVC. generally, plain PVC is white (or grey if it's UV stabilized) and CPVS is light brown, almost flesh tone.

Thanks, the info was good.

Granted, I'm no cook, but this would seem to "solve" your problem. When the macaroni is done to perfection, you put the pot in the sink and run cold water into it. It stops the macaroni from getting overcooked in those last few minutes and leaves you with not boiling water to drain off. Besides your PVC dilemma, should you really be pouring boiling water down the drain if you can avoid it? You run the risk of burning yourself in the process (I've slopped some boiling water on me at times-not fun).
Just a thought.

JaysMom, I don't think the issue was how to not pour off boiling water but rather whether it would affect the pipes. But your concern for safety is a good one and something to keep in mind.

My plumber told me to run hot water down all my drains for about 5 minutes weekly. that's a lot of water, especially at the cost that the municipality charges.

But I do pour boiling water down the drains whenever I have it from cooking, or after running the water first thing in the morning to let the lead run out. I don't have the same kind of pipe that the OP has though. Still, I find I have to do it to help keep the drains clear.

This message has been edited. Last edited by: GardenSprite,

the boiling water helps clear out soap gunk and any stray grease that might have gotten in the drains and turned into hard knobs.