dslreports logo
 
    All Forums Hot Topics Gallery
spc
uniqs
26

ArgMeMatey
join:2001-08-09
Milwaukee, WI

ArgMeMatey to nunya

Member

to nunya

Re: Question for plumbers

As in IL, here in WI a dishwasher drain hose could not be connected to the food grinder (the term used in the code) connection intended for that purpose.

However, I understand the code was changed recently to allow it.

My understanding was that the reason this was not allowed was that in case there was unground food in the grinder preventing the sink from draining, and you ran the dishwasher, the dishwasher could back up into the sink. Given that, I have no idea what the rationale was for changing it.

Maybe before the days of the vacuum breaker, there was a fear of the sprayer hose being left in the sink, and the sink backing up while there were simultaneously conditions for backflow, and the water supply being thereby contaminated.

I'd be interested in a history lesson on this issue.
towerdave
join:2002-01-16
O Fallon, IL

towerdave

Member

said by ArgMeMatey:

As in IL, here in WI a dishwasher drain hose could not be connected to the food grinder (the term used in the code) connection intended for that purpose.

However, I understand the code was changed recently to allow it.

My understanding was that the reason this was not allowed was that in case there was unground food in the grinder preventing the sink from draining, and you ran the dishwasher, the dishwasher could back up into the sink. Given that, I have no idea what the rationale was for changing it.

Maybe before the days of the vacuum breaker, there was a fear of the sprayer hose being left in the sink, and the sink backing up while there were simultaneously conditions for backflow, and the water supply being thereby contaminated.

I'd be interested in a history lesson on this issue.

The reason given to me by the plumbing inspector was that the disposals were wearing out early due to the water (and maybe what's in it?) coming from the dishwasher. Which doesn't really make sense to me, but I'm not a plumber.

TD

cdru
Go Colts
MVM
join:2003-05-14
Fort Wayne, IN

cdru

MVM

said by towerdave:

The reason given to me by the plumbing inspector was that the disposals were wearing out early due to the water (and maybe what's in it?) coming from the dishwasher. Which doesn't really make sense to me, but I'm not a plumber.

Yes, because hot water with detergent is pretty caustic to stainless steel and plastic, which was what almost all the disposals were made of last time I looked at them. I can maybe see that it keeps the grinder wet so it might corrode, but I run my sink faucet far more then my dishwasher so I don't think that could even be it.
towerdave
join:2002-01-16
O Fallon, IL

towerdave

Member

said by cdru:

said by towerdave:

The reason given to me by the plumbing inspector was that the disposals were wearing out early due to the water (and maybe what's in it?) coming from the dishwasher. Which doesn't really make sense to me, but I'm not a plumber.

Yes, because hot water with detergent is pretty caustic to stainless steel and plastic, which was what almost all the disposals were made of last time I looked at them. I can maybe see that it keeps the grinder wet so it might corrode, but I run my sink faucet far more then my dishwasher so I don't think that could even be it.

Ok, that makes sense. I'm not a chemist either, but I can see that, and he may have even mentioned the detergents.

Either way, it's code in IL. And I'm glad he mentioned it to me when he did, because we had a new disposal and hadn't punched out the knockout yet.

Before we re-did the kitchen the DW was draining into the disposal, but that wasn't an inspected installation.

TD

cdru
Go Colts
MVM
join:2003-05-14
Fort Wayne, IN

cdru

MVM

said by towerdave:

said by cdru:

Yes, because hot water with detergent is pretty caustic to stainless steel and plastic, which was what almost all the disposals were made of last time I looked at them. I can maybe see that it keeps the grinder wet so it might corrode, but I run my sink faucet far more then my dishwasher so I don't think that could even be it.

Ok, that makes sense. I'm not a chemist either, but I can see that, and he may have even mentioned the detergents.

I said that with sarcasm. Plastics and stainless steel are going to be pretty immune to hot water and dish washer detergent. Your plumbing inspector was feeding you a line of bull.

Hall
MVM
join:2000-04-28
Germantown, OH

Hall

MVM

said by cdru:

Plastics and stainless steel are going to be pretty immune to hot water and dish washer detergent.

Hehe, I'd hope so else everyone's dishwashers would rot away !
towerdave
join:2002-01-16
O Fallon, IL

towerdave to cdru

Member

to cdru
said by cdru:

said by towerdave:

said by cdru:

Yes, because hot water with detergent is pretty caustic to stainless steel and plastic, which was what almost all the disposals were made of last time I looked at them. I can maybe see that it keeps the grinder wet so it might corrode, but I run my sink faucet far more then my dishwasher so I don't think that could even be it.

Ok, that makes sense. I'm not a chemist either, but I can see that, and he may have even mentioned the detergents.

I said that with sarcasm. Plastics and stainless steel are going to be pretty immune to hot water and dish washer detergent. Your plumbing inspector was feeding you a line of bull.

Either way, it didn't matter why. And because it didn't cause me any headache, I was happy to comply.

TD