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bsivell1
Sep 4, 2018, 08:39 AM
I have a 30 gallon electric water heater that is 220v. It has the standard 10/2 wiring going to 2 15 amp circuits at the panel. Can I made 240v using the same 10/2 wiring and 2 15 amp circuits. If not what changes do I have to make?

ma0641
Sep 4, 2018, 12:59 PM
220 VAC has not existed in the US for quite a while, it has been 240VAC. Today, power is supplied to you home in two 120 VAC phases. No changes are needed. Are you replacing the HW heater?

massplumber2008
Sep 4, 2018, 02:18 PM
Hi Bsivell

Your breakers are SERIOUSLY undersized here. You should have a 30 AMP double pole breaker for a water heater... that is a 1 piece 30 Amp double pole breaker that supplies 30 amp to each leg of the water heater. In fact, this is a dangerous set up that could eventually lead to someone (usually a homeowner) getting hurt because they might make the mistake of shutting only one breaker off thinking they shut off the entire circuit, go to work on the water heater and get zapped with some serious juice, right?

Consider updating the panel to a 30 AMP double pole breaker for safety sake (much more efficient heating water using correctly sized breakers! ).

Agree with Ma0641 on 220V vs 240V... get a meter

Mark

Milo Dolezal
Sep 5, 2018, 10:22 AM
Very good point, Mark. Glad you noticed this Code violation, and brought it to Bsivell1's attention

Milo

massplumber2008
Sep 5, 2018, 02:03 PM
I appreciate that, Milo. I just hope Bsivell returns to the thread!

Good day!

Mark

ma0641
Sep 5, 2018, 07:19 PM
If the OP is using a 15 AMP on a 10AWG, it won't hurt anything, just really heats the water much more slowly. However, it sure is easy to snap in a double 30, that's what I have in our mountain cabin.

Stratmando
Sep 10, 2018, 08:50 AM
Poster never mentioned Watts. Many/Most are 240 Volts on a 30 Amp 2 Pole Breaker.
15 Amp Breaker(s) should have tripped. 15 Amps @ 240 Volts is 2880 Watts.
15 X 240 = 2880.
At least the wire is Correct, as Mentioned by massplumber, 2 Pole 30 is needed

Stratmando
Sep 13, 2018, 07:50 AM
#12 may be correct depending on Watts?