Dishwasher nightmare followed by mould

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Jmaclicious
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Dishwasher nightmare followed by mould

Post by Jmaclicious » Wed Dec 18, 2019 5:30 pm

So I was trying to eliminate some junction boxes by running new home runs and ran into a nice surprise. I was checking to see how the dishwasher was hard-wired, noticed it was MC cable from a junction box downstairs up through the hole underneath the dishwasher that went into the hard-wired box on the unit itself. Opened up the box and sure enough, burnt wires... I disconnected everything, pulled the unit out and found another surprise, BAM Black mould! I remember a while back when the electrician changed out the panel he put the Dishwasher on a 15a circuit.. I looked at pictures from a long time ago and remember it being on a 20a circuit. So I checked the wire thicknesses and compared to both a 12/2 and 14/2 rome's I had laying around. It appears the old MC wire that was running from a 20a cct to the dishwasher is only 14/2. I notice theres a dry stain probably old water leak on the sub floor.. (the fresh water was the supply hose dripping after i removed it)..

Which brings me to my next question.

1.) How the hell do I go about cleaning this mess up to install a new dish washer (do not wish to re-do the entire kitchen at this time)

and 2.) If I get a new dishwasher, can i run another power line if done in normal romex and use the same hole in the subfloor underneath the dishwasher as well? (the picture i took, the power hole didn't make it into the picture as its too far forward.

Heres pics! I will be looking online for some new ones in the mean time :(
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Aaron
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Re: Dishwasher nightmare followed by mould

Post by Aaron » Wed Dec 18, 2019 8:57 pm

Yikes. I'm guessing there was some sort of leak from the dishwasher, perhaps even a small one--enough to keep everything damp and allow mould to grow. You need to kill that mould. I would get a nice high quality spray bottle and fill it with white distilled vinegar and liberally douse the whole cavity. Then use a stiff brush with baking soda and scrub it down. The acid should kill and clean up the mould.

When the wall is fully dry, apply Zinsser Mould Stop primer on the wall before putting the dishwasher back in. A good topcoat is Zinsser Perma-White.

For electrical, I suggest you use the armoured cable, it's what's needed for flexible permanent electrical cable that is not behind walls. Honestly I think 15A is fine enough for a dishwasher, but there may be a plate or tag on the dishwasher that specifies its current requirements.

Jmaclicious
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Re: Dishwasher nightmare followed by mould

Post by Jmaclicious » Wed Dec 18, 2019 9:18 pm

Aaron wrote:
Wed Dec 18, 2019 8:57 pm
Yikes. I'm guessing there was some sort of leak from the dishwasher, perhaps even a small one--enough to keep everything damp and allow mould to grow. You need to kill that mould. I would get a nice high quality spray bottle and fill it with white distilled vinegar and liberally douse the whole cavity. Then use a stiff brush with baking soda and scrub it down. The acid should kill and clean up the mould.

When the wall is fully dry, apply Zinsser Mould Stop primer on the wall before putting the dishwasher back in. A good topcoat is Zinsser Perma-White.

For electrical, I suggest you use the armoured cable, it's what's needed for flexible permanent electrical cable that is not behind walls. Honestly I think 15A is fine enough for a dishwasher, but there may be a plate or tag on the dishwasher that specifies its current requirements.
I like this suggestion, saves my kitchen! I won't die touching this black mold though will I? :P I mean i did it before, just not on wood/drywall! :mrgreen: :geek:

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Aaron
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Re: Dishwasher nightmare followed by mould

Post by Aaron » Thu Dec 19, 2019 12:44 am

Might not hurt to wear a respirator as you're cleaning. Have a fan running out a window for ventilation. Can't be too careful.

Put a coat of that Mould Stop on that subfloor too.

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emtnut
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Re: Dishwasher nightmare followed by mould

Post by emtnut » Thu Dec 19, 2019 8:26 am

Jmaclicious wrote:
Wed Dec 18, 2019 5:30 pm
So I was trying to eliminate some junction boxes by running new home runs and ran into a nice surprise. I was checking to see how the dishwasher was hard-wired, noticed it was MC cable from a junction box downstairs up through the hole underneath the dishwasher that went into the hard-wired box on the unit itself. Opened up the box and sure enough, burnt wires...
I remember a while back when the electrician changed out the panel he put the Dishwasher on a 15a circuit.. I looked at pictures from a long time ago and remember it being on a 20a circuit. So I checked the wire thicknesses and compared to both a 12/2 and 14/2 rome's I had laying around. It appears the old MC wire that was running from a 20a cct to the dishwasher is only 14/2.

and 2.) If I get a new dishwasher, can i run another power line if done in normal romex and use the same hole in the subfloor underneath the dishwasher as well? (the picture i took, the power hole didn't make it into the picture as its too far forward.
15A is plenty for any dishwasher I've seen. As Aaron said, you could look at the nameplate to be sure.

Romex is fine for the wiring, since it's not exposed.

I'm certain that the neutral is charred from a bad connection. It can be a bit tricky trying to wirenut a solid wire and a stranded one.
I usually strip the solid about 3/4" , and the stranded about 1 1/4" so I can wrap alot of it around the solid.
Another option would be a Wago lever nut connector.

*Edit to add* That wirenut may also be too big. I think they are for 2 #14s. The stranded is probably #16 awg.

In that connection box, I see there is a box connector for the incoming line, but it looks like the 2 wires going to the machine are run thru a metal hole ! If a box connector fits in that hole, I'd put one in. If not, let us know, there are other options.
Last edited by emtnut on Thu Dec 19, 2019 8:38 am, edited 1 time in total.
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Shannon
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Re: Dishwasher nightmare followed by mould

Post by Shannon » Thu Dec 19, 2019 8:32 am

That extra hole does have a rolled edge on it so it is not sharp . I see that on almost every dishwasher now for the wires coming from the unit to the hook up area.
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emtnut
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Re: Dishwasher nightmare followed by mould

Post by emtnut » Thu Dec 19, 2019 8:35 am

Shannon wrote:
Thu Dec 19, 2019 8:32 am
That extra hole does have a rolled edge on it so it is not sharp . I see that on almost every dishwasher now for the wires coming from the unit to the hook up area.
Thanks Shannon, good to know. I'm pre-programmed to freak out if I see wires thru a metal hole !! :lol:
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Aaron
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Re: Dishwasher nightmare followed by mould

Post by Aaron » Thu Dec 19, 2019 12:40 pm

Yeah I'd feel better seeing a plastic grommet or bushing of some sort.

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Shannon
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Re: Dishwasher nightmare followed by mould

Post by Shannon » Fri Dec 20, 2019 8:00 am

Aaron wrote:
Thu Dec 19, 2019 12:40 pm
Yeah I'd feel better seeing a plastic grommet or bushing of some sort.
Yes that would be better to see but this edge really is not sharp at all, it still seems to set off an internal alarm when you see that kinda thing though! :lol:
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Aaron
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Re: Dishwasher nightmare followed by mould

Post by Aaron » Fri Dec 20, 2019 5:39 pm

Yah I am uneasy seeing NM up in the trusses of the garage stapled to the frame like 4" away from the nail-on gusset plate. Lol