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sidney alstad
10-28-2010, 01:41 PM
Observed at 70 amp breaker for a Whirlpool Gold range/oven today at a condo built in 1979. This seems a bit oversized. Wiring was proper sized for the breaker. Would you write this up as unusual with evaluation needed?

Roger Frazee
10-28-2010, 03:30 PM
Observed at 70 amp breaker for a Whirlpool Gold range/oven today at a condo built in 1979. This seems a bit oversized. Wiring was proper sized for the breaker. Would you write this up as unusual with evaluation needed?

HI Sidney

Yeah that's a bit oversized for a whirlpool gold range. I don't think Whirlpool is even manufacturing a range/oven that requires a 50 or 60 amp branch circuit. Looking at the manufacturers website all the gold series only require 40 amp branch circuits.

What wire size and what type of wire ...... NM-B, SER, or possibly THHN wire in conduit ?

Also are you sure you had the branch circuit correctly identified as serving that range/oven?

Jerry Peck
10-28-2010, 04:30 PM
There is nothing wrong with a 70 amp breaker protecting the circuit to the range - the breaker does not protect the appliance, it protects the circuit - *AS LONG AS* the conductors the 70 amp breaker is protecting are rated for at least 70 amps.

Do you know what size wire went to that breaker?

sidney alstad
10-28-2010, 04:43 PM
#4 AL serviced the 70 amp breaker.

ken horak
10-28-2010, 04:46 PM
There is nothing wrong with a 70 amp breaker protecting the circuit to the range - the breaker does not protect the appliance, it protects the circuit - *AS LONG AS* the conductors the 70 amp breaker is protecting are rated for at least 70 amps.

Do you know what size wire went to that breaker?

Let me add to Jerry's reply:

It will also depend on if the range is cord and plugged. If that range has a receptacle behind it and that receptacle is fed with that 70 ampere feed, then it is wrong. You are not allowed to put a 40 or a 50 ampere rated receptacle on a 70 ampere circuit.

Jerry Peck
10-28-2010, 04:49 PM
Let me add to Jerry's reply:

It will also depend on if the range is cord and plugged. If that range has a receptacle behind it and that receptacle is fed with that 70 ampere feed, then it is wrong. You are not allowed to put a 40 or a 50 ampere rated receptacle on a 70 ampere circuit.


Correct.

I was thinking permanently wired, not cord and plug connected. My error as that makes a HUGE difference.

sidney alstad
10-28-2010, 04:55 PM
There was no access behind the range as it was built in to the cabinet. I guess this should be evaluated by a licensed electrical contractor. There were other electrical issues, receptacles with reversed polarity, open grounds, etc.
Also there was a 100 amp breaker and a 60 amp breaker servicing the original 1979 Lennox electric furnace. The furnace unit had 2 60 amp breakers and a 30 amp breaker; the data plate stated a maximum circuit breakers of 60/50/25. What's up with this?...It appears that two of these breakers at the furnace unit are oversized.

Your comments are welcome

Jerry Peck
10-28-2010, 05:35 PM
I guess this should be evaluated by a licensed electrical contractor.


Nope ... it does not need to be "evaluated" ... it needs to be "repaired as needed".

If you leave it to the electrician to "evaluate" it, it might be the same electrician who installed it that way.

Just come right out and say it needs to be repaired as needed by a licensed and competent electrical contractor.

Phil Brody
10-29-2010, 05:29 AM
" There is nothing wrong with a 70 amp breaker protecting the circuit to the range - the breaker does not protect the appliance, it protects the circuit - *AS LONG AS* the conductors the 70 amp breaker is protecting are rated for at least 70 amps."

I disagree, manufactures specify maximum breaker size based on maximum normal current draw. If a fault was to develop in the appliance the properly sized breaker would trip to possibly avoid further damage.

Roger Frazee
10-29-2010, 08:32 AM
I disagree, manufacturers specify maximum breaker size based on maximum normal current draw. If a fault was to develop in the appliance the properly sized breaker would trip to possibly avoid further damage.

I think you will find that to be not the case. A maximum breaker size listed on the nameplate is generally restricted to motor operated utilization equipment like air conditioning and refrigeration appliances. Normally when a manufacturer wants overcurrent/overload protection for a specified piece of equipment like a electric furnace they will factory install supplementary protection at the equipment. The branch circuit ends at the outlet where the equipment sources its power and that is also where the NEC ends. After that any protection for equipment is the responsibility of the manufacturer.

Also a maximum breaker based on 'normal current' draw seems a bit odd to me is there a source where you received that information?

Phil Brody
10-29-2010, 02:11 PM
I agree with what you state but as an appliance designer for 5 years we rated the appliance under a variety of conditions and aging. When we specd. the ratings, it was under the worst "normal" operating conditions. When over-current protection was not specifically indicated at the unit(s) (as accessibility was always an issue) we relied on the external over-current protection to safeguard the unit. That is why we would recommend changing the breaker in the original post to something consistent with the appliance spec.

Jerry Peck
10-29-2010, 05:55 PM
When we specd. the ratings, it was under the worst "normal" operating conditions. When over-current protection was not specifically indicated at the unit(s) (as accessibility was always an issue) we relied on the external over-current protection to safeguard the unit. That is why we would recommend changing the breaker in the original post to something consistent with the appliance spec.


I checked a new installation instructions (no access to an old installation instruction) and it says nothing about overcurrent protection size, just about 40 amp or 50 amp circuit size, and the cords for those: http://www.whirlpool.com/assets/pdfs/product/ZINSTALL/GGE388LXS_Installation%20Instruction_EN.pdf

Mike Locurcio
10-29-2010, 06:06 PM
I'd be tempted to look at the appliance receptacle. You'd have to shave that wire to feed 40 amp terminals with #4 aluminum. Not good.

Phil Brody
10-29-2010, 07:13 PM
On page 4 it does state "circuit protection", then it also states a circuit breaker is recommended which can be left up to interpretation but I don't give the technical writer a high grade on that one.


Range Rating* Specified Rating of
Power Supply Cord Kit
and Circuit Protection
120/240 Volts 120/208 Volts Amps
8.8 - 16.5 KW
16.6 - 22.5 KW
7.8 - 12.5 KW
12.6 - 18.5 KW
40 or 50**
*The NEC calculated load is less than the total connected load
listed on the model/serial/rating plate.
**If connecting to a 50-amp circuit, use a 50-amp rated cord with
kit. For 50-amp rated cord kits, use kits that specify use with a
nominal 1³⁄₈" (34.9 mm) diameter connection opening.
■ A circuit breaker is recommended.

Phil Brody
10-30-2010, 06:16 AM
Also there was a 100 amp breaker and a 60 amp breaker servicing the original 1979 Lennox electric furnace. The furnace unit had 2 60 amp breakers and a 30 amp breaker; the data plate stated a maximum circuit breakers of 60/50/25. What's up with this?...It appears that two of these breakers at the furnace unit are over-sized.

Sidney,in this case it is fine as long as the conductors from the 100 and 60 breakers were sized appropriately since the manufacture safeguards the unit with it's own over-current protection.

Bruce Adams
10-30-2010, 07:08 AM
Sidney
This is wrong needs replace with proper size breaker according to the manufacture. Whirlpool Gold calls for forty amp. Wire can be oversized. The NEC is to protect the home and it occupants. No appliance is have an oversized breaker except the Air conditioner. And that is to be just one size over. If the Air Conditioner calls for a 30 amp breaker it can have a 40 amp breaker for starting loads.
The range or any other appliance is to have the size stated by the manufacture.
You can go the the NEC to 422.11 and see what it says.
If a protection device rating is marked on an appliance ,the branch-circuit overcurrent device rating shall not exceed the protective device rating marked on the appliance.

I would hate to read or hear after I did an inspection that there was a fire in this home caused by the range.
Bruce Adams

Garry Sorrells
10-30-2010, 08:12 AM
Sidney:
Did you ever consider calling/contacting Whirlpool directly to obtain spec on that model. Get it from the horses mouth?

Roger Frazee
10-30-2010, 08:44 AM
I don't recall any manufacturer in my experience listing a maximum breaker size or any breaker size on a range nameplate. They generally list the wattage of the range and the installation instructions will list a minimum recommended branch circuit size. NEC states in 210.19(A)(3) that the minimum circuit size for ranges of 8.75 Kw or more shall be 40 amps. Meaning I need branch circuit conductors that are rated at a minimum of 40 amps. If I choose that method and the conductors I install are exactly 40 amp rated then I would be required to install a maximum 40 amp OCPD for those conductors since my ampacity falls on a standard breaker size. There is nothing however that would keep me from installing 55 amp conductors and placing that on a 50 or 60 amp breaker other than what John stated in a cord and plug application. If I cord and plug the range I would need to restrict the OCPD to 50 amps in order to use a 10-50R or 14-50R receptacle depending on 3 wire range or 4 wire range respectively. Remember the circuit breaker size in amps determines the branch circuit rating not the ampacity of the wire.

As for the existing #4 aluminum wire and not having a picture we really cannot be certain that it is even a legal wiring method in accordance with NEC 250.140. Assuming it is legal then it almost certainly will be a 60C ampacity rating in my experience. So #4 aluminum has a 55 amp rating ... under that criteria the 70 amp breaker would be a violation in this application for a range circuit. The existing breaker could be 70 amps if it is a 75C application ( 65 amp rating and next size up rule) and the conductors are installed in conduit.

So as for the branch circuit being correct we need some clarification.

It would be speculation but I would say that the installation is an older one and I have seen #4 al used for range circuits in 1950 - 1970 or so 3 wire range circuit installations in my experience. However the terminations on the appliance end were generally incorrect or questionable. Sometimes they ran an SE or other cable all the way to the range terminal block and sometimes to a junction box.

It was more common to see # 6 al used in the older 3 wire installations and operating the range on 40 amp rated conductors using a 40 amp circuit breaker.

Keep in mind some homeowners are very resourceful so anything can happen with the branch circuit wiring from the load center to the range terminal block.....:D

Anyway I would certainly question/report and recommend the circuit and/or OCPD be corrected as necessary....Jerry and others have already made this statement but just being a little redundant never hurts.

H.G. Watson, Sr.
10-30-2010, 02:05 PM
I am more than suspicious regarding the details supplied as described.

FIrst of all, I question the condo 1979 vintage as new construction in 1979 as a condo. This same condo seems to have been discussed on more than one thread (i.e. unlevel floors) See (although he's since altered some of the posts) this thread here: http://www.inspectionnews.net/home_inspection/building-interior-home-inspection-commercial-inspection/22227-uneven-concrete-flooring-condo.html.


Next I am doubtful as to the wiring or descriptions as given. On what basis did you determine the size and type of conductor. It would not be the first time this OP has confused coated conductors. Next, A multi-floor condo building would not have a service panel in the unit.

Most likely this condo is not split single phase 120/240, but poly phase; i.e. 208/120.

Terminology is often (regularly) ambgious from this poster, for example here a whilrpool gold kitchen appliance is refered to as a oven/range and is later described as being built into the cablnets. A range is not a wall oven. A cooktop is not a range. IMO nothing can be taken at face value or assumed when it comes to terminology or statements, no offense Sidney Alstead, but we've been here before.

No pictures have been supplied. Details are wishy-washy and I don't trust them to be accurate, or complete.

I'm not picking up any of what the OP is putting down (I'm not confused, I'm just not trusting the accuracy of what has been shared, nor its completeness).:rolleyes: ;)

Roger Frazee
10-31-2010, 08:38 AM
Sidney

HG is making some very good points regarding the descriptions in your posts. Don't take it personally .. a few pictures of what your describing would help us a bunch to get over the questions about what you have there.....:)

The 70 amp breaker for a range branch circuit or any branch circuit for cooking equipment in the kitchen of a condo is not your norm and as said in earlier replies is almost certainly not correct. I've never seen a 70 amp breaker in a condo panel for a range branch circuit...:eek:

# 4 aluminum is also really odd though not impossible as I have seen it done but not in a condo complex. The insulation on older wiring can make a conductor look ' fatter ' than what you might think. You need to read the wiring labeling on the outer insulation or sheath. You may have done this but just saying .... :)

ken horak
10-31-2010, 04:56 PM
Just to add some more confusion to the subject that HG has already posted about ranges/ cook tops/ wall ovens.
Keep in mind when it comes to ranges there are 2 types - Free standing and Drop in. Drop in ranges do fit into the base cabinet. They do not have the bottom drawer and set on a cabinet base.

Roger Frazee
10-31-2010, 09:20 PM
Yes and I think it is possible a drop in style range is what Sidney is referring too ....

http://s1.hubimg.com/u/2982528_f260.jpg

Rod Cicotte
11-01-2010, 07:19 AM
Let me add to Jerry's reply:

It will also depend on if the range is cord and plugged. If that range has a receptacle behind it and that receptacle is fed with that 70 ampere feed, then it is wrong. You are not allowed to put a 40 or a 50 ampere rated receptacle on a 70 ampere circuit.

Ken is correct. Regardless of components internal protection devices or lack thereof, the plug and it's receptacle will determine the size of the circuit. If the unit is hardwired, no plug/receptacle, the manufacturer would state circuit/load size. Rod

Roger Frazee
11-01-2010, 08:38 AM
I think all responding understand that a 70 amp branch circuit to a range is not your normal/correct installation. Manufacturers will list a minimum recommended circuit size for the chosen range in the installation instructions. If that happens to be 40 amps then you can run a 40 amp branch circuit using a 40 amp breaker. But if you wish to cord and plug the range and have a circuit size that will accomodate any possible upgrades that are not commercial in nature in the future you can run a maximum 50 amp branch circuit so you can use a 50 amp rated 14-50 4 wire receptacle. The manufacturer is not restricting you to 40 amps only ... this is a minimum circuit size.

70 amps is overprotection for #4 aluminum under a 60C application NEC table 310.16 and following the rules in article 240.

And as Ken has stated you would not be able to cord and plug at 70 amp rating.

If this is a drop in range then it will be hard wired in a junction box as you will not have a drawer to remove to access the range cord for disconnection which along with a fixed in place cabinet installation is the point Ken is making.

John Kogel
11-01-2010, 09:02 AM
Sidney has his answer, the place needs to be checked over by an electrician.

Mis-labeled breakers. In the future, if a breaker size seems wrong, try shutting it off and operating the appliance. People switch breakers around all the time and don't make corrections to the label.

Number 2 - check for a remote panel in the kitchen which could be feeding more than just the oven.

I found this one hiding with the pots and pans. "Junior, be careful with mommy's frying pan".

John Arnold
11-01-2010, 09:07 AM
... People switch breakers around all the time and don't make corrections to the label...

Label? They label them where you are?! Sweet.

Bruce Adams
11-01-2010, 09:35 AM
Sidney has his answer, the place needs to be checked over by an electrician.

Mis-labeled breakers. In the future, if a breaker size seems wrong, try shutting it off and operating the appliance. People switch breakers around all the time and don't make corrections to the label.

Number 2 - check for a remote panel in the kitchen which could be feeding more than just the oven.

I found this one hiding with the pots and pans. "Junior, be careful with mommy's frying pan".

John
I hope you reported this panel as incorrect. Because it does not meet the requirements of the NEC.
Bruce

John Kogel
11-01-2010, 12:05 PM
John
I hope you reported this panel as incorrect. Because it does not meet the requirements of the NEC.
BruceNo fear, it is wrong on all counts in my country as well. :)

Just making the point, expect the unexpected. Like if you shoved the handle of a fry pan into that panel opening.

John A. Yes we occasionally see a label or directory with all the breakers correctly marked.

Lou Romano
11-01-2010, 03:20 PM
Ken got it right when he said it can't be cord and plug at 70-amp! You can't feed a 50-amp rated outlet at 70-amps. If this stove truly requires a 70-amp circuit it must be hardwired!