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Forum topic by SeattleD posted 06-28-2013 06:07 PM 1001 views 0 times favorited 8 replies Add to Favorites Watch
View SeattleD's profile


15 posts in 1821 days

06-28-2013 06:07 PM

I recently moved into a townhouse with a decent sized 2 car garage, following a divorce. I had a major shop previously, and would like to set up a smaller one in my new house. The limitation has been that there is only ONE 15 amp 120v outlet in the space. There is however a 240V water heater on 30 amp breakers in the garage, fed by 10/3 w/ground, hard wired at the heater. My plan is to replace the hard wire connection at the heater with a suitable plug/outlet (as used on a range or dryer, selected for sufficient amperage) which I can disconnect in order to use the 240v source as needed for shop machines. I’m not sure if this is “code”, but I see no reason this should not work or be any kind of a safety hazard from a technical standpoint, and I can easily switch it back to hard wired prior to moving out in the future. Does anyone know if putting a water heater on a plug/outlet connection is a code issue? Any other thoughts appreciated. I should say I am very experienced with basic electrical work, and have done a fair bit of it. The townhouse was built around 2007.


-- David

8 replies so far

View pmayer's profile


1028 posts in 3087 days

#1 posted 06-29-2013 02:31 AM

It would work but I don’t think it would meet code. You could install a transfer switch but that might be kind of spendy. Hopefully there is a way to get another circuit out there one way or another so you can have a more convenient solution.

-- PaulMayer,

View wiser1934's profile


524 posts in 3169 days

#2 posted 06-29-2013 02:50 AM

the best way to do it is to install a subpanel fed by the 30 amp 220 volt line. i would say a 100 amp subpanel would work well. one with at least 8 full size spaces. then run you 120 volt outlets off the subpanel using 15 amp s.p. breakers. do not forget to install a ground bar in the subpanel

-- wiser1934, new york

View BigRedKnothead's profile


8517 posts in 2004 days

#3 posted 06-29-2013 02:52 AM

Don’t see any problem with it….other than taking a while to get hot water again when you go back in the house;-)

30 amps is too small for a sub panel.

-- "At the end of the day, try and make it beautiful....because the world is full of ugly." Konrad Sauer

View SeattleD's profile


15 posts in 1821 days

#4 posted 06-29-2013 03:38 AM

Thanks for the replies. This place is basically 3 floors, the garage is the ground floor, and the main breaker box is on the 3rd floor. If it were in the garage, or even on the 2nd floor, I’d just run another line, but going from the top floor, especially in a rental, where I can’t go toooooo nuts with modifications, is more than I should do here. It seems to me that if the outlet, plug, & line to the heater are all up to the current draw, there should really be no safety issues. But I sure wish that breaker box was in the garage!

-- David

View runswithscissors's profile


2762 posts in 2047 days

#5 posted 06-29-2013 05:07 AM

Again, the old electrical dilemma. Better you than me. (sorry)

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

View Nowater's profile


16 posts in 1962 days

#6 posted 06-29-2013 05:30 AM

Look for a waste line vent and see if it gets you close to the panel and your garage. Sometimes that is a good way between floors.

View MrUnix's profile


6757 posts in 2221 days

#7 posted 06-29-2013 07:03 AM

For a fairly safe and clean setup, get a double throw safety switch like this one at HD.

Your existing 30A circuit will feed the switch which can then select between the water heater or a 30A receptacle. The water heater can be wired directly to the switch so you don’t need to be constantly plugging and unplugging the thing.


-- Brad in FL - In Dog I trust... everything else is questionable

View toolie's profile


2134 posts in 2650 days

#8 posted 06-29-2013 10:22 AM

good suggestion from mrunix. i’d offer two additional ideas relative to his suggestion. look for a lower rated similar switch to reduce the cost. a 30A rated similar switch will work safely and cost less. next, attach a 6 circuit sub panel to the non HW side of the double throw switch if you’d like more than just one more 220v receptacle. i run my entire shop on a 30A sub panel. additional wiring from the sub panel is simple and could be surface mount ed for removal should you move elsewhere.

-- there's a solution to every just have to be willing to find it.

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