Anyone have experience with drains for a steam oven?

[Rossn]

Does anyone have experience setting up drains for a steam oven, such as the Miele DGC 6705-1? Drains are covered on p 183 of this manual, but I'm not clear if this ties in similar to how a dishwasher would connect to a drain port on a disposal? Or... does it require it's own trap, etc. I am sure volume is quite low.

If it's own trap - I'm assuming that we could call this 1/2 DFU, akin to a drinking fountain, and use 1-1/4" trap with 1-1/2" drain.

I would probably tie it into a bar sink, which I assume is 1 DFU, and the drain running to this area is currently 1-1/2", which I believe can support 3 DFUs. All that soud good?

 

[Jeff H Young]

might require going to a indirect waste or an airgap? likely needs protection.

 

[Sponsor]

 

[WorthFlorida]

This specification sheet has a drainage requirement paragraph. It does mention an air gap but then the picture shows it connected like a dishwasher.

https://us.mieleusa.com/MieleMedia/...tourLine DGC 6705-1 XL_Spec_Plumbed_FINAL.pdf

 

[Jeff H Young]

This specification sheet has a drainage requirement paragraph. It does mention an air gap but then the picture shows it connected like a dishwasher.

https://us.mieleusa.com/MieleMedia/docs/products/specs/pdf/dg/ContourLine DGC 6705-1 XL_Spec_Plumbed_FINAL.pdf

it says drain hose can be run high to provide proper air gap. then has totally contradicting picture showing no air gap or high loop.
Not to mention that a high loop is not an " air gap " at all. many codes allow D/w connections with a high loop but have never heard of a high loop to be a" proper air gap " because it is not an air gap .
frustrating poor manufactures instructions, but in my code UPC I would expect a problem passing inspection without air gap

 

[Rossn]

Thanks guys - yes, totally confused by the mfg docs. Does it make sense to get a dedicated drain to the location beneath the cabinet where the steam oven will live?

The kitchen remodel (with new appliances, layout, cabinets) isn't coming for another couple years, but all the plumbing, electrical, wall-reframing, range hood ducting, etc is getting done with the current remodel.

 

[Jeff H Young]

I tried to do alittle checking and a dishwasher looks like it requires a 1 inch airgap in Colorado. hopefully someone a little better on your code or familiar with this steam oven chimes in . just wondering is that being pumped? you might not want a dedicated stack as keeping it primed may be an issue. hopefully a place to run it to is nearby

 

[Rossn]

Thanks, Jeff. Appreciate the help.

I'm not sure if it is pumped... details are vague. I have not necessarily chosen this steam oven, but am looking for one that is plumbed, to minimize daily maintenance (recommendation from a friend). There aren't many that are plumbed, and I'll see if I can find some other reference. When I called Miele today they didn't sound very confident and mentioned a dedicated trap. Once installed, I think it will see quite a bit of use and likely be OK on the keeping-the-trap-full.

Should I decide run a dedicated stack (2x4 studs on exterior wall with 1" exterior continuous foam), can I set this up like a washer box (if available), with a 1-1/4" welded trap in the wall, or is that a no-no? I'd have to use an AAV for venting in this case.

 

[Rossn]

So far, I've only found the Miele and Gaggeneau ovens to be plumbed. Below are the Gaggeneau instructions.

3/4" Supply needed??? It also calls out 2.6 GPM. Using a 3/4" supply seems bizarre. I know it has a washing/cleaning function, but can't imagine that requires a 3/4" supply.

Sounds like they also want a 1-1/2" trap.

For the Miele, it sounds like they want a 3/4" threaded union? I'm definitely not clear why they are calling for a union:

"The water intake hose must be connected to the drinking water supply by a faucet with a ³/₄" threaded union. If this is not present, one must be installed by a suitably qualified plumber"

 

[Reach4]

For the Miele, it sounds like they want a 3/4" threaded union? I'm definitely not clear why they are calling for a union:

"The water intake hose must be connected to the drinking water supply by a faucet with a ³/₄" threaded union. If this is not present, one must be installed by a suitably qualified plumber"

I would guess that the union would be for serviceability.

That 3/4 size, if NPT or NPS, would seem let you use a corrugated metal flex line intended for water heaters. Those might be considered to double as a union. You would not want a line with a braided covering because the inside rubber can deteriorate.

 

[Rossn]

The funny thing is that both mfg's (apparently only 2 make plumbed steam ovens)mention that you cannot extend or shorten the drain line, which appears to be plastic. My guess is that is part of the cooling the water before it enters the drain.

Since this kitchen work would be a couple years out, best I can figure I would run and cap a 1-1/2" drain beneath the adjacent cabinet, as well as a 1/2" water line (with a remote cutoff valve), and then the subfloor could be cut and final plumbing completed within the cabinet when installed.

I saw a reference in a diy forum that mentioned (paraphrased): "classified waste due to temp of discharge, and temp must be reduced to 140F before it enters the drain system" and "for food prep, must use an indirect drain".

Can anyone confirm these two comments? I know Jeff mentioned an air gap for the dishwasher, and knowing the bottom of the steam oven would maybe 6-12" above the flood level of other appliances, I'm not clear if that air gap is required. I am pretty sure the Gaggenau mentioned backup prevention, though I'm not sure about Miele.

 

[Plumber01]

I install combi ovens in commercial kitchens and restaurants all the time. I had no idea they make a residential model. This wont be much help but in a commercial setting the drains are plumbed indirect to a floor sink. The water connection is 3/4" hose thread, run through a filter and backflow preventer.

The drain water temp is very hot typically 180 degrees and must run through a drain tempering kit before it enters the drainage system if plumbed with schedule 40 ABS or PVC. Sometimes we use cast iron to get around that and sometimes the plans call for cast iron for that very reason.

In your situation i would run the drain through a dishwasher airgap. The Miele you spec'd says it discharges at approx 160. 3/8" water connection to a standard angle stop. Install and hookup to the manufacturers guidelines with the exception of the airgap aforementioned. I guess Miele expects the drainage system to hold up to those temperatures?

 

[Jeff H Young]

for some reason it shows a maximum height on the drain connection of 19 11/16 inches so running up to an air gap like we use for a D/W on the counter top might not be an option. I did see the spec on do not shorten drain hose, I thought of excess heat as well . I usually dont do this much thinking lol. Wouldnt hurt to call manufacture they probebly will have some good staff to help. and if you do Rossyn share what they tell.
Plumber01 mentioned running through a D/W air gap Im thinking that might be to high trapping water all the way to bottom of sink. (manufacture says keep below 19 11/16 for some reason)
This stuff supposed to be figured out for us ?

 

[Rossn]

Thanks, guys! Yeah, I did call Miele and they almost seemed confused and didn't give any information not already known. The supposed discharge temp is 160F, and I don't know for sure, but suspect that is why they don't allow trimming down the drain hose... maybe it drops another 5 degrees before it exists.

On a couple sites, I found a working temperature of ABS up to 170F. I know I regularly pour a pot of boiling pasta water down the drain, though I think about the heat a lot and you might say 'don't do that'

For now, I'll just rough and cap the drain to the location of the cabinet that will be next to the steam oven and call it good. I can sort through all the other stuff later.

 

[Jeff H Young]

ok good enough. would not expect the most knowlegeable people there to help on 3rd or 4th of july sat or sunday. but worry about if and when you need makes sence