Arizona CJ
New Member
I'm trying to install an overflow fitting for a "kitchen" sink. It's actually going in a laundry room, but for all practical purposes (usage) it's a single bowl stainless steel kitchen sink with a disposal. It'll have one trap. (Or, if I have to, I could put a waterless trap on the overflow and join the lines downstream).
I put an overflow in the old laundry sink, and it worked great for many years. But there was no disposal then, plus it was easy to make a hole in that sink (plastic). That overflow was a re-purposed bathtub overflow. I'm probably going that route again (I can't seem to find kitchen sink overflows online that'll ship to the USA). This means cutting holes in the new steel sink, which looks like the hardest part of the job.
My question is the plumbing connections. I'm going to have the disposal and the sink overflow (functionaly the same as a bathtub overflow) joining (upstream of the trap, of course). I'd prefer to do this with a wye, or failing that, a san T. (with the overflow coming in from the side). I'm also thinking flexible line for the overflow (due to the shapes and angles it has to deal with). It almost never carries water, so as long as I can keep outflow from the disposal going up it, I hope it'll work. My other option for the overflow pipe is radiator hose. (I'm leaning that way; it's less prone to trapping gunk). I will be using standard fittings for the rest of the plumbing under the sink (I know it's never a good idea to use flex line for actual wastewater).
Accordion pipe is what kitchen sink overflow kits come with (they are commonplace in Europe and the far east) so I figure it's okay for this (no issues with my old one, either). The only worry I have is I've never hooked up a sink overflow to a disposal drain before. I'm tempted to use the disposal's dishwasher port, but I think the diameter is too small for the flow (I measured the faucet outflow at 3.2 GPM).
In case anyone is wondering why I'm so hell-bent on an overflow for this sink, it's for my mom's house, and she's always (even when young) been prone to starting the sink filling then forgetting it. Thus, I've always made certain every sink she has has an overflow (it's prevented several floodings already).
My priorities, in order, are;
#1, Safety.
#2 flood damage/water damage protection.
#3 code (UPC).
Does my plan sound viable? If not, what should I change to make this work? I'm concerned on this one because I've never hooked a disposal and a sink overflow to the same trap before, and I'm worried there may be pitfalls I'm not aware of.
I put an overflow in the old laundry sink, and it worked great for many years. But there was no disposal then, plus it was easy to make a hole in that sink (plastic). That overflow was a re-purposed bathtub overflow. I'm probably going that route again (I can't seem to find kitchen sink overflows online that'll ship to the USA). This means cutting holes in the new steel sink, which looks like the hardest part of the job.
My question is the plumbing connections. I'm going to have the disposal and the sink overflow (functionaly the same as a bathtub overflow) joining (upstream of the trap, of course). I'd prefer to do this with a wye, or failing that, a san T. (with the overflow coming in from the side). I'm also thinking flexible line for the overflow (due to the shapes and angles it has to deal with). It almost never carries water, so as long as I can keep outflow from the disposal going up it, I hope it'll work. My other option for the overflow pipe is radiator hose. (I'm leaning that way; it's less prone to trapping gunk). I will be using standard fittings for the rest of the plumbing under the sink (I know it's never a good idea to use flex line for actual wastewater).
Accordion pipe is what kitchen sink overflow kits come with (they are commonplace in Europe and the far east) so I figure it's okay for this (no issues with my old one, either). The only worry I have is I've never hooked up a sink overflow to a disposal drain before. I'm tempted to use the disposal's dishwasher port, but I think the diameter is too small for the flow (I measured the faucet outflow at 3.2 GPM).
In case anyone is wondering why I'm so hell-bent on an overflow for this sink, it's for my mom's house, and she's always (even when young) been prone to starting the sink filling then forgetting it. Thus, I've always made certain every sink she has has an overflow (it's prevented several floodings already).
My priorities, in order, are;
#1, Safety.
#2 flood damage/water damage protection.
#3 code (UPC).
Does my plan sound viable? If not, what should I change to make this work? I'm concerned on this one because I've never hooked a disposal and a sink overflow to the same trap before, and I'm worried there may be pitfalls I'm not aware of.
