Range Feed: Swap Aluminum for Copper?
Good day all,
Still plugging away on my basement project – trying to take care of details before framing and drywalling.
Our current, all electric, double oven range is being fed by an aluminum cable on a 40 amp breaker, about 10 feet in length and about 23 years old. We’ve never experienced any problem with it but, as I have heard, many real electricians (which immediately excludes me) prefer copper.
Probably immaterial but I’ll mention it anyway, the current range will be going away about a year from now, replaced with a duel fuel (gas burner, elec oven) unit.
So, while I have easy access to it, should I consider replacing the aluminum cable with copper? Given the same load rating, is there a gauge difference between aluminum and copper?
Many thanks,
Dan
Replies
Aluminum is fine when properly installed. It's common to use it for high amperage circuits. Your service entrance is probably aluminum.
When working with aluminum the devices (i.e. outlets, breakers, whatever the wires are connected to) must be rated and marked to accept aluminum. The wires must be coated with an anti-oxidizing agent made specifically for this purpose. Connections must be torqued tightly.
If these were done, I would not disturb the existing wiring to replace it.
Thanks for the feed back Wayne (electrical? feed back? Bawhahahah... Ok, maybe it wasn't that clever). Indeed, the main service is aluminum.
I've already distrubed it once. I'm sistering all my floor joists and had to remove the cable because it was running through two joists that I wanted to sister. I disconnected it at the breaker and pulled it from the panel. I did note the anti-oxidizing paste on the ends.
Thanks again.....
Dan
Since you disturbed it once.. Go back and check the tightness of your connections....
Who ever invented work didn't know how to fish....
Good point.
He also needs to know that copper and alum. wires have different amperage rating fo the same size wire. No point in paying for a #6 gauge cu. to replace a #6 ga. alum., when a #8 cu. will do the job.
Dave
While I agree with Wayne's concept in general since you will be replacing the stove I would go ahead and replace the circuit.
Many stoves require 50 amp circuits. Of course that is for a full stove and I don't know about a dual fuel uni. But also some ovens have higher power heaters.
And if this is not a one for one replacement (stove for stove), but are remodeling the kitchen and moving stuff or going with a a cook top and separate oven(s) then I would definitly run a new cable and leave it extra long to that you can relocate it.
Also your existing circuit is probably the old style 2 hots with a neutral and should be upgraded to a 2 hots, neutral, and ground.
Also I don't know if a dual fuel stove requires a separate 120 volt circuit or not. A pure gas stove or a separate gas cook top would. So I would go ahead and put in a 120 receptacle now.
And of course run the gas line now, if needed.
Thanks Bill. You are correct, 2 hots and 1 neutral.
The kitchen will be re-modeled but the cook top/range will remain in it's current location and I've already got someone lined up to run the black pipe for the eventual gas hook up. The kitchen plan calls for a dual-fuel cooktop/oven combo, one of those nifty new microwave/conventional oven combos' over the cook top, and an exhaust fan mounted on the outside wall of the house, hopfully controlled by the exhaust fan switch on the microwave/oven combo.
Which brings up an interesting point. I'd better find out what the microwave/oven combo needs to be fed with. I don't suppose there's any way I can determine the electrical mounting location before hand so perhaps I can just run a line up into the empty wall cavity behind the existing range, thread them through the joists, and wait to do the hook ups at the panel until it's time to do the kitchen.
An excellent point regarding the gas cook top needing 120 to light the burners, thanks for that. Looks like I'll need one 120 outlet for the cook top at the standard height from the floor, and another further up the wall positioned behind the MW/oven.
With all this "pre-work" that I need to do to correct some things and allow for the future it'll be a miracle if I ever start framing the basement!
Dan
For the 120 outlet for the gas cooktop, "standard" height may not be the best. You'll cut a hole in the back of the cabinet to expose the outlet so you can plug in the stove. You might want the outlet a little higher so it doesn't show, or so the cord is run up higher out of the way. But not behind a drawer or in the way of a shelf. So, look inside your existing cabinets for a good height.
I was thinking an outlet at standard height off the floor behind the existing slide-in double oven range to be used to power the ignition system for the gas cook top. I don't yet know if I will be using a separate cook top and oven, or another slide in unit. I do know I'll need an outlet for the under cabinet mounted microwave but I don't know yet where that outlet should be (I don't think there's space for it directly behind the unit as I believe these types of MW mount to both the wall and the cabinet above). I was hoping I could do with one 20 amp circuit to power the MW, the cook top ignition, and the exhaust fan but I'll probably be safe and run two 15 amp circuits.
IMERC, Dave, Wayne, Bill, that for all your feed, and patients. I'm just a DIY'er trying to get it right.
Dan
The microwave hood thing I just installed had a plug on it. The cord came out the top and required a standard outlet inside the cabinet above. The microwave was also a quarter inch wider than the spec sheet said it was supposed to be. Needed a little fancy chisel work on the adjacent cabinet to get the door to open.
Couple of thoughts come to mind. If you know the make/model of the new appliances, almost all manufactures now have their tech specs available online. If not, I'm sure a hard copy can be had (usually available from the dealer). That should take most of the guesswork out of requirements for power consumption and location. If you haven't picked out specific models, now might be the right time. Better than having to cut into that brand new drywall job you just finished. :)
I'll probably be safe and run two 15 amp circuits.
I wouldn't run 15 amp circuits to a kitchen. It may not even be allowed in some places. I'm not sure of that for your purposes, but I'm pretty sure NEC requires 20 amp for countertop circuits, seems logical they would require it for other things in kitchens.
Planning these projects can be fun, but planning for all the details can be very time consuming. Especially the first time or two.
Yeah Mugsy, the planning is rather fun, but for a DIY'er like me also quite a challenge. The goal is to think of everything necessary to prepare the kitchen for it's remod next year so I don't have to open the ceiling of the new basement which would - in a word, suck.
To make the preparation task more difficult is the fact that we don't know exactly which appliances/brands we will be using. So I'm leaning towards just running a couple of 12/3 lines into the wall cavity behind the existing range and just leave the other end tied off above the panel in the basement.
Dan
That sounds like a plan and takes care of any needed 110 lines. But, what if the new oven/range requires 50 amp breaker and appropriate wire. Alot do. That would be the hardest line to snake in after the fact. My advice would be to at least narrow down your choices of appliances, check the specs on them and run the biggest cable you would need for any of them. No harm, except a couple extra pennies, in running too large of a cable.
You might consider arranging a few well placed access panels, nicely finished wood panels fastened into place with screws so they can be removed easily. This and running a few empty conduits can allow adding circuits later a comparative breeze. I often advise this in dedicated offices in homes it would apply in this case as well.
We just installed a frigidaire dual fuel unit, and it didn't need a separate 120.
Yes, I imagine a duel fuel, slide in unit would probably only need the 220/240 feed.
My existing all electric dual oven slide in range also has an exhaust hood that matches the unit, but the hood plugs into the a small recess located in the top right rear of the upper oven, and the exhaust fan is powered by 120v - there is not a separate 120v feed for the fan.
However, we are considering a drop in gas cook top and a separate electric oven - and not necessarly from the same manufacturer.
Dan