Gas Ranges & Dryers vs Service Load Calculations

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ptrombley

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I provided an electrical load calculation for a SFR that has a gas dryer and a gas range. It is wired for both a 240V electric range and dryer, but the homeowner chose to install gas appliances.
I included the dryer's motor load and 180VA for the range (controls, light)... but the inspector wants me to include 5kW for the dryer and 8kW for the range.
Is he correct, per the NEC... and what if the house was not wired for an electric range and dryer... does that make a difference?
If you can provide Code references, that would be appreciated. Thank you.

Paul
 
No article 220.54 clearly states use 5kw for electric dryers. I think the inspector wants to cover the load if someone changes them to electric-- not his job. Range is 220.55
 
Thanks Dennis.
Have you heard of this being an issue before? I've submitted a lot of load calcs for residences and haven't had this redline before.
With that said, I can see where plans examiners and inspectors might jump to the conclusion that the 5kW and 8kW minimums must be included for all SFR's.
 
ptrombley said:
Thanks Dennis.
Have you heard of this being an issue before? I've submitted a lot of load calcs for residences and haven't had this redline before.
With that said, I can see where plans examiners and inspectors might jump to the conclusion that the 5kW and 8kW minimums must be included for all SFR's.
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To be honest I have never been asked to do a load calculation for a residence.
 
There is no requirement in the NEC that says a residential circuit/receptacle provided for possible future use needs to considered/added for a load calculation.

Range and dryer circuits are not mandated here:

III. Required Outlets
210.50 General. Receptacle outlets shall be installed as
specified in 210.52 through 210.63.

Nor are they mandated in 220 calculations here:

II. Branch-Circuit Load Calculations
220.10 General. Branch-circuit loads shall be calculated
as shown in 220.12, 220.14, and 220.16.
 
If you have wired for it to be 240V and 120V, why would you not add the 240V loads to your calcs ? If you have wired for a 30A 240V dryer circuit and a 40A 240V range, you must be expecting at some point they will change to electric from gas, or you wouldn't prep for it, why not make the service able to carry the load too ?????????????
 
ptrombley said:
... It is wired for both a 240V electric range and dryer...
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How does one wire a dwelling for an electric range and electric dryer and not include them in the load calculation??? It is either wired for such, or not. IMO, whether the receptacles are used or not is not the issue.

what if the house was not wired for an electric range and dryer... does that make a difference?
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IMO, yes. If there was no wiring installed for these appliances, the inspector wouldn't have a leg to stand on.
 
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Smart $ said:
IMO, yes. If there was no wiring installed for these appliances, the inspector wouldn't have a leg to stand on.
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Not sure I agree with you here. If the dryer and range circuits are disconnected then I don't see why the load is necessary to be figured in. If I run a #10 wire to a circuit for a 15 amp motor I don't have to include 30 amps in my calculation.

IMO, I would include the electric setup so that my feeder or service could handle a change over. I don't see how the inspectror can enforce that.
 
Dennis Alwon said:
Not sure I agree with you here. If the dryer and range circuits are disconnected then I don't see why the load is necessary to be figured in. If I run a #10 wire to a circuit for a 15 amp motor I don't have to include 30 amps in my calculation.

IMO, I would include the electric setup so that my feeder or service could handle a change over. I don't see how the inspectror can enforce that.
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I can understand that if you ran 10AWG for the dryer but installed a 120 volt receptacle and intend to plug in the gas dryer - similar for the range. The load calculation needs re evaluated at the time the electric range or dryer is installed and the receptacles and breakers get changed.

If you install a working range receptacle and a working dryer receptacle (for electric heat source units) as well as install 125 volt receptacles so there is a choice of gas or electric why wouldn't you need to include the higher loads in the load calculations? You may not even know which appliance will be used and that may be why you included receptacles for both.
 
kwired said:
I can understand that if you ran 10AWG for the dryer but installed a 120 volt receptacle and intend to plug in the gas dryer - similar for the range. The load calculation needs re evaluated at the time the electric range or dryer is installed and the receptacles and breakers get changed.

If you install a working range receptacle and a working dryer receptacle (for electric heat source units) as well as install 125 volt receptacles so there is a choice of gas or electric why wouldn't you need to include the higher loads in the load calculations? You may not even know which appliance will be used and that may be why you included receptacles for both.
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While I think it is a good idea to include it in the load calcs, please show me where I have to? I can install ten 30A circuits in a SFD and if there is no specific load, not add in 1A to my load calcs. No? Future possible loads are not mandated.

If I put ten SABCs to a kitchen, what is the mandated load? 3000VA.
 
NEC 220.52 says you use 1500VA for EACH small appliance branch circuit installed. You have to install 2 for the kitchen and one for the laundry. You can choose to install more and to me it seems like they would be counted at 1500 VA each.

NEC 220.54 says a dryer circuit is counted at 5000VA or the dryer nameplate, whichever is more. With no planned dryer, each one will have to be counted at 5 KVA.

For a range, this one is tougher. You have NEC table 220.55, and one could argue that you've never seen a range under 8 3/4 KW which would land you in column C. The smallest demand for a range in column C is 8 KW. I think if you did not install a range receptacle and just put a blank cover there, you could argue that no specific circuit was provided so no calculated value need be used.

If you're using the optional calculation, there is this: "All appliances that are fastened in place, permanently connected, or located to be on a specific circuit". I would argue that providing a range or dryer receptacle is locating a specific circuit for that appliance. There is always a quandry of what load to use when you're wiring a house and appliances have not been selected yet (or may never be selected if just a provision was made). In that case, I would use a nameplate from a typical appliance of that type.
 
If the house was wired with electric range and electric dryer and the appliance are not there then I don't see why it needs to be calculated. The old house had it but the new upgrade did away with it.

If I had central electric heat with 10kw heat strips and I change the unit to a gas furnace would you still calculate the house with 10kw if you left the disconnect connected?
 
The distinction is a receptacle -vs- a hard wired circuit to nowhere. A receptacle is a completed usable circuit. A J box with no whip is not. The code specifically covers some of these receptacle circuits with minimum load values. I don't necessarily agree with counting more than the required SABC circuits, but it says to count them if you install them.

You can add as many bathroom circuits as you want and not count those...
 
Depends on what the receptacle is for. If it looks like a dryer receptacle, then its 5 KVA. If it looks like a SABC circuit, 1500 VA per circuit. If a commercial general use receptacle, 180 VA per strap. Not sure how many more items are covered in the code with mandated minimum values, but I think that is most of them.

I would say you can have as many NEMA 5-30 receptacles as you want without any calculated load unless the room they are in looks like a laundry room.
 
jumper said:
While I think it is a good idea to include it in the load calcs, please show me where I have to? I can install ten 30A circuits in a SFD and if there is no specific load, not add in 1A to my load calcs. No? Future possible loads are not mandated.

If I put ten SABCs to a kitchen, what is the mandated load? 3000VA.
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Ok, if I were an inspector and it were questionable whether or not you were able to supply an additional range or dryer with your service or feeder I would not be able to give you any solid code reference that says you must account for the range or dryer in the load calc.

As an electrician I think it is unwise and will make you look foolish to install a receptacle for something and not have capacity to handle the load should the receptacle ever get used.

Reality check: unless you only have 100 amp service that is otherwise at max capacity you likely can add an electric range and dryer and get away with it even if it puts you over some on load calc. Demand on most dwelling services (except for electric heat or AC demands) is generally not nearly as high as what Art 220 calculations come up with.
 
Dennis Alwon said:
Not sure I agree with you here. If the dryer and range circuits are disconnected then I don't see why the load is necessary to be figured in. If I run a #10 wire to a circuit for a 15 amp motor I don't have to include 30 amps in my calculation.

IMO, I would include the electric setup so that my feeder or service could handle a change over. I don't see how the inspectror can enforce that.
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OP says house was wired for electric range and dryer. As long as recpt's are fully functional, I say they need be included in calculation... simply because any resident, even though it may be in the future, that decides to change from the existing gas to electric, will not contact anyone to verify the premises wiring and service rating is adequate. They will just plug in the appliances and sleep good at night.

Disconnect wiring and pull from panel so that recept's are non-functional, then IMO you can omit the range and dryer loads from the calc'. I'd even go as far as to tag the pulled wires and note reason.

PS: Not a Code issue... but it is one of liability.
 
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Smart $ said:
OP says house was wired for electric range and dryer. As long as recpt's are fully functional, I say they need be included in calculation... simply because any resident, even though it may be in the future, that decides to change from the existing gas to electric, will not contact anyone to verify the premises wiring and service rating is adequate. They will just plug in the appliances and sleep good at night.

Disconnect wiring and pull from panel so that recept's are non-functional, then IMO you can omit the range and dryer loads from the calc'. I'd even go as far as to tag the pulled wires and note reason.

PS: Not a Code issue... but it is one of liability.
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Common sense aside: required or not.
 
kwired said:
Ok, if I were an inspector and it were questionable whether or not you were able to supply an additional range or dryer with your service or feeder I would not be able to give you any solid code reference that says you must account for the range or dryer in the load calc.

As an electrician I think it is unwise and will make you look foolish to install a receptacle for something and not have capacity to handle the load should the receptacle ever get used.

Reality check: unless you only have 100 amp service that is otherwise at max capacity you likely can add an electric range and dryer and get away with it even if it puts you over some on load calc. Demand on most dwelling services (except for electric heat or AC demands) is generally not nearly as high as what Art 220 calculations come up with.
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OP asked if it was required, not if it was common sense.
 
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