What is the reason hot water should not be introduced in to waste systems

It will promote bacteria growth.

Terbewar, which test are you preparing for? Where did you hear or read that hot water should not go to waste, we do it daily.

what is the reason hot water should not be introduced in to waste systems

Where did this come from? What do you think goes down the drain when you bathe or shower? That's right sports fans, hot water!!

Can you give a little more detail about your question. Above answers are dead on. We put hot water down drains everyday. Now, in some areas there is a code that limits the temp of hot water that can enter a drainage system. My code says no hotter than 140 degrees, but I see commercial dishwashers that are putting in 180 degree water into drain and no problems. Please let me know what your thinking, I'm curious.

what is the reason hot water should not be introduced in to waste systems

Thanks to all of you.

I am taking a re-certification test and this is one of the questions. I believe the answer is D.

The principle reason wastes should not be permitted to enter a regular domestic drainage system at a temperature higher than 140 degrees is that at a higher temperature:

A. bursting of the pipes is likely to result.

B. self-siphonage of the fixture traps would occur

C. water and waste products are more corrosive at higher temps

D. fixture traps and piping are subject to stoppage.

Re-certification test for what, cooking? Our domestic hot water heaters are usually set at 120 tops, when we drain a tub the water is about 95 degrees. What are you draining where the waste water is still 140?? I'd go with A if someone forced my hand. Then again I'm thinking you have a text to read or a class to attend, right?

I would also go with A. However, question remains: what is this test for? Plumbing license ?

My guess is C...

In my area, we can't have water exceed 130F, with exceptions.

Check out this link for more information:

Drinking Water Corrosion, Corrosivity, Saturation Index, and Corrosion Treatment (http://www.water-research.net/corrosion.htm)

As presented at the link above, "It is important to keep in mind that the corrosiveness of the water can be increased by the installation of water softeners, aeration devices, increasing hotwater temperatures, chlorinating the water and improper matching of metal pipes. Some water treatment equipment such as softeners and aeration systems can aggravate corrosion. Softeners remove the protective calcium and magnesium, and introduce highly conductive sodium into the water. Aeration devices for iron, sulfur or odor removal add oxygen, which is extremely corrosive in water. Higher water temperatures and suspended materials accelerate the rate of corrosion by increasing the reaction rates or causing physical damage to the pipes. Chlorine is a strong powerful oxidant which can promote corrosion.

In terms of bursting the pipes I just don't see that as a possible answer... ;) I'm thinking of the 180 degree water used in commercial dishwashers and the 190 degree instant hot water devices we see all the time and have never seen BURST pipes as a result. Heck I'm even thinking of the 212 degree water from steam systems that I have seen so many apprentices throw down drain pipes... and never saw any issues, but knew that it wasn't approved.

However, I have seen increased corrosion (thinning and eventual breakdown/leak of the copper pipes) at copper pipes associated with these higher temperature fixtures/devices.

I also don't see D as a good answer as I have not seen increased blockage at dishwashers/sinks/indirect waste lines.

I am not claiming to be 100% correct here, all... just throwing up my thoughts... :)

MARK

e principle reason wastes should not be permitted to enter a regular domestic drainage system at a temperature higher than 140 degrees is that at a higher temperature:

A. bursting of the pipes is likely to result.

B. self-siphonage of the fixture traps would occur

C. water and waste products are more corrosive at higher temps

D. fixture traps and piping are subject to stoppage.

And I say; None of the above. Hot water will clog traps and pipes? Ridiculous!
What's to clog?
What test are you setting for that would ask a silly question like that?

Wow, now I know how it feels, lol. I would also say C. Have to look into this. There are many silly questions like this on test these days. Id like to meet the guy that wrights these things up. Do you have the answer to this question, or are you going to take our advice? If you have the answer, please let us know what it is, and what type of test you are taking, and if a plumbing exam, what code?

Are you a licensed plumber now, and taking a recirt test? If you are indeed a plumber, you may be interested in the post,, (Any interest here?) Check it out and feel free to jump in.

Yes, I am a plumber, 30 yrs and counting. I belong to a union plumbers and pipefitters local. We are required to take a 100 question test to certify, then every three yrs. After that. It is a recertification test and it is given by an independent firm called NITC ( national inspection testing certification) There are really a lot of stupid questions that we as plumbers really do not need to know. We are not engineers! My son is also in the trades and has all the books from his apprenticeship training. I will look it up and let you know what I find.

Bear,
What Plumbing Code do you fall under? Regards, tom

Speedball
I am using the UPC. I am in calif.
All the code. Questions that are on the test are taken from the 2006 code book. The test is made up from all the aspects i.e. sizing water, waste, and gas. Backflow devices. Yadda yadda

Bear,
What Plumbing Code do you fall under? Regards, tom
Speedball
I am using the UPC. I am in calif.
Okeh! You've just explained all those silly questions to my satifaction. I just knew that any code that said putting hot water down a drain would clog up the traps would have to be UPC. Thanks, Tom

I think, in California, hot water is know to cause cancer in some lab animals too. LOL