hard wired cooktop safe removal

17 years ago

I am replacing my old self contained range with a cooktop. The unit is hardwired in, no plug. I've never wored with 220 before but I understand that I'll need to trip 2 breakers to ensure the power is shutoff before removing the range. What is the best way to determine when I have tripped both breakers? I have a volt meter capable of testing for 220 and 110. Inside the jbox there appear to be three wire nutted connections, one black, one red, and one copper (ground, I assume). How would I use this tester on the red and black to know when there was no juice on those wires?

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Comments (9)

DavidR
17 years ago
You shouldn't have to open two breakers. The rangetop should be connected to a double-pole breaker (twice the width of the other breakers). If it isn't, it was installed in violation of code. (I've seen a 240v central air-con unit improperly wired to two separate breakers.)

To test, set meter on 200 volts range or higher. Touch one probe of the voltmeter to the metal junction box. Touch the other to the red and black wires in turn. You should read close to zero volts, or at least something under about 20 volts.

If both are zero or nearly so, as a backup check, set the meter to 500 volts or higher. Touch one probe to red and the other to black. You should again read only a very small voltage reading, if any.

It's safer and better, IMO, to test with a test light or Wiggy, for several reasons.
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kurtmcmouth
Original Author
17 years ago
David,

Thanks for the quick response. You may be right about it only being a single breaker. The home was built back in 77, so I guess I was assuming it'd be 2 breakers.

The volt meter I have does not have a switch on it. only two probes and a light for 110 and a light for 220.

Any reason I couldn't do the backup or final check with this meter? i.e. why the need to set the meter to 500?

Thanks again!
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DavidR
17 years ago
The home was built back in 77, so I guess I was assuming it'd be 2 breakers.

No, code has never permitted 240 volt circuits fed by separate breakers unless they were next to each other and their handles were physically fastened together. Sometimes two FUSES have been used, however.

The volt meter I have does not have a switch on it. only two probes and a light for 110 and a light for 220.

Ah, OK. That's not what I call a meter, but no matter. It should be fine. Don't worry about setting it for anything.
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User
17 years ago
I see an issue (no neutral) with the new cooktop which will likely
require 120/240 unlike the old stove which was 220 only.

Regards
Chris
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kurtmcmouth
Original Author
17 years ago
The new cooktop has red, black, and green only. I am assuming it also does not need 110 since it is a stand alone unit with no clock, no light, etc.
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kurtmcmouth
Original Author
17 years ago
Okay, having a little issue here with the install and hoping someone who knows more than me about electrical (which shouldn't take much) can help me out here.

I connected red to red, black to black, and green (from the stove) to the ground in the house.

Problem is once I turn a burner on, and then off, the stove light stays on and the burner stays warm.

Any thoughts?
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hendricus
17 years ago
Is this an indicator light that says the burner is on? Our new stove has indicator lights for when the burner is on and also for hot surface, I still get them mixed up and check to see if the burner is actually turned off. Takes a while for the stove top to cool and lights to go out.
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kurtmcmouth
Original Author
17 years ago
Turns out the cooktop on/off light doesn't turn off until the burners have cooled off, not simply when the switches are off. Think I'm all good now.
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joed
17 years ago
Those glass top ranges will leave the indicator light on as a saftey feature because you can't tell if a burner is on by looking at it. It would easy to set something down on top of a hot burner and not realize it.
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hard wired cooktop safe removal

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hard wired cooktop safe removal

Comments (9)

DavidR

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