Please help? I'm not sure if my electrician is calculating correctly..

[evdryst]

My electrician calculated my service load and came up with a number that a friend of mine (who knows more than me but is also not an electrician) was surprised at. I did some digging and now I also think he might be wrong. Could someone double check this for me, please? He is using the standard calculation. My concerns are underlined.

1950 sq ft house
2 general circuits
1 laundry unit
= 3000@100% and 7350@75% = 5573

A/C
= 6500 (larger than heating) I'm not sure how he got to this number. I took a look at the A/C and it's a 4 ton (Aspen Manufacturing CE48F34-175L-004). From a calculations spreadsheet I downloaded from this site, it looks like it uses 5700VA? Not sure. The label on the blower (Goodman 0131F00022SP) says 115V and "less than 12A". Isn't that 1380VA? Together that is 7080.

Fridge 180
Freezer 565
Dishwasher 1300
Disposal 1224
Hood 610
Wine cellar 144
Garage door opener 720
= 4743*75%=3557

Largest motor (disposal) 1224*25%
= 306 Should this not be calculated on the A/C since it's larger than the disposer? In other words 5700*25%=1425?

Gas dryer
= 5000 I don't agree with this, but according to my electrician: "The reason is because all dryers, even gas, have a big heating element inside that consumes alot of power in order to start the flames in the flutes." Is this correct?
Electric cooking appliances
1 Microwave/oven combo
= 10200 Should I not take from table 220.55, column C, 1 appliance = 8000?

His calculations come to 130AMP load, and I have 100AMP service. My calculations brings me to 106AMP, so I'm still over, but if I'm right I'd understand how to tweak my appliances (like that disposal that can turn chicken bones to dust

Thanks in advance for any help.

 

[iwire]

My electrician calculated my service load and came up with a number that a friend of mine (who knows more than me but is also not an electrician) was surprised at. I did some digging and now I also think he might be wrong. Could someone double check this for me, please? He is using the standard calculation. My concerns are underlined.

1950 sq ft house
2 general circuits
1 laundry unit
= 3000@100% and 7350@75% = 5573

A/C
= 6500 (larger than heating) I'm not sure how he got to this number. I took a look at the A/C and it's a 4 ton (Aspen Manufacturing CE48F34-175L-004). From a calculations spreadsheet I downloaded from this site, it looks like it uses 5700VA? Not sure. The label on the blower (Goodman 0131F00022SP) says 115V and "less than 12A". Isn't that 1380VA? Together that is 7080.

Fridge 180
Freezer 565
Dishwasher 1300
Disposal 1224
Hood 610
Wine cellar 144
Garage door opener 720
= 4743*75%=3557

Largest motor (disposal) 1224*25%
= 306 Should this not be calculated on the A/C since it's larger than the disposer? In other words 5700*25%=1425?

Gas dryer
= 5000 I don't agree with this, but according to my electrician: "The reason is because all dryers, even gas, have a big heating element inside that consumes alot of power in order to start the flames in the flutes." Is this correct?
Electric cooking appliances
1 Microwave/oven combo
= 10200 Should I not take from table 220.55, column C, 1 appliance = 8000?

His calculations come to 130AMP load, and I have 100AMP service. My calculations brings me to 106AMP, so I'm still over, but if I'm right I'd understand how to tweak my appliances (like that disposal that can turn chicken bones to dust

Thanks in advance for any help.

First off I am only allowing this post because you have an electrician working on this and you are not doing it yourself.

That said, if I did a calculation that came to any level over 100 you would be getting a 200 amp service.

 

[evdryst]

I wish..

I wish..

It seems I forgot to mention I'm in a townhouse and the HOA won't allow me to upgrade the service..

 

[JFletcher]

Gas dryers plug into a standard 120V outlet and would use an igniter to light the gas, not a 5kw heating element. The only load is the motor to turn the drum and blower, quite low compared to electric heat.

Do you have gas hot water or electric?

What sized service and panel is he planning to install, or is he?

I dont know why the NEC even considers garbage disposals since they run a few seconds on max load. A hairdryer or vacuum cleaner pulls more current for far longer.

 

[ptonsparky]

Gas dryers do not draw 5000 watts.


Why are you having this calculation done now?

 

[Ingenieur]

2 general circuits
1 laundry unit
= 3000@100% and 7350@75% = 5573
3000 + 0.75 x 7350 = 8513
????

 

[GoldDigger]

Gas dryers do not draw 5000 watts.

:thumbsup:
These days they either have a spark igniter that probably consumes at most 20W when actually sparking, and turns off once the flame ignites or a glow bar element which might actually use a few hundred watts and remain on all the time.

Then there is the motor.....

 

[Ingenieur]

Gas dryers do not draw 5000 watts.


Why are you having this calculation done now?

just looked at a few
120 w/15 A ocpd
I'd call it 1500 va

 

[evdryst]

Clarifications

Clarifications

We're having the kitchen redone with new appliances, so needed to have the calculations done. We can't have the service upgraded (stuck with 100amp), but the panel can be upgraded if needed.

"3000 + 0.75 x 7350 = 8513": 75% was a typo, meant to be 35%.

Gas hot water.

Thanks so far.

 

[ptonsparky]

We're having the kitchen redone with new appliances, so needed to have the calculations done. We can't have the service upgraded (stuck with 100amp), but the panel can be upgraded if needed.

"3000 + 0.75 x 7350 = 8513": 75% was a typo, meant to be 35%.

Gas hot water.

Thanks so far.

Are you adding occupants to the home? Will the fridge see more door openings? More clothes washed than in the past? Put in a panel with more spaces if you feel you need them but most likely all your appliances will be more efficient than the old. Your lighting should be. Your actually load may go down.

 

[evdryst]

Are you adding occupants to the home? Will the fridge see more door openings? More clothes washed than in the past? Put in a panel with more spaces if you feel you need them but most likely all your appliances will be more efficient than the old. Your lighting should be. Your actually load may go down.

Perhaps it will in the end, but according to the calculations it's adding up to more than 100amps..

I had some specific questions which I'm still wondering about. Pretty sure I do not have to put in anything for the gas dryer, but
1) Do I have the correct VA for the A/C and blower?
2) On which motor do I calculate the extra 25% on? The electrician used the disposal, but shouldn't it be the A/C?
3) Do I use 10200 for the combination oven or the 8000 from the table?

Thanks in advance, I'd highly appreciate any answers.

 

[ptonsparky]

in ferhaps it will in the end, but according to the calculations it's adding up to more than 100amps..

I had some specific questions which I'm still wondering about. Pretty sure I do not have to put in anything for the gas dryer, but
1) Do I have the correct VA for the A/C and blower?
2) On which motor do I calculate the extra 25% on? The electrician used the disposal, but shouldn't it be the A/C?
3) Do I use 10200 for the combination oven or the 8000 from the table?

Thanks in advance, I'd highly appreciate any answers.

Go to the MH home page and look for the free resources, select Industry, find the residential calculator.

It will be an exercise In Futility if your HOA still limits you to a 100 amp service. Good luck.

 

[Dennis Alwon]

What are you adding to the kitchen that is different than before? A disposal and garage door openers , IMO, should not even be in the calculations as they are running for less than a minute- not even enough time to overload the breaker.

Reality is I sincerely doubt you will ever get close to 100 amps.

The electrician is incorrect about a dryer- gas dryers do not have elements so I agree with the other-- can the 5000 watts.

The oven needs to be taken at 100%.

 

[augie47]

We're having the kitchen redone with new appliances, so needed to have the calculations done. We can't have the service upgraded (stuck with 100amp), but the panel can be upgraded if needed.

"3000 + 0.75 x 7350 = 8513": 75% was a typo, meant to be 35%.

Gas hot water.

Thanks so far.

If you can;t upgrade the service all the concern about the panel in naught. A properly protected (at the supply end) 100 amp service feeding a 200 amp or 400 amp panel is still a 100 amp service and changing out the panel can possibly give you more breakers and a warm-fuzzy feeling but it's still limited to the capacity of the 100 amp supply.
If your 100 amp service is not protected at the supply end, then a 100 amp panel is all you can install.

 

[david luchini]

My electrician calculated my service load and came up with a number that a friend of mine (who knows more than me but is also not an electrician) was surprised at. I did some digging and now I also think he might be wrong. Could someone double check this for me, please? He is using the standard calculation. My concerns are underlined.

1950 sq ft house
2 general circuits
1 laundry unit
= 3000@100% and 7350@75% = 5573

A/C
= 6500 (larger than heating) I'm not sure how he got to this number. I took a look at the A/C and it's a 4 ton (Aspen Manufacturing CE48F34-175L-004). From a calculations spreadsheet I downloaded from this site, it looks like it uses 5700VA? Not sure. The label on the blower (Goodman 0131F00022SP) says 115V and "less than 12A". Isn't that 1380VA? Together that is 7080.

Fridge 180
Freezer 565
Dishwasher 1300
Disposal 1224
Hood 610
Wine cellar 144
Garage door opener 720
= 4743*75%=3557

Largest motor (disposal) 1224*25%
= 306 Should this not be calculated on the A/C since it's larger than the disposer? In other words 5700*25%=1425?

Gas dryer
= 5000 I don't agree with this, but according to my electrician: "The reason is because all dryers, even gas, have a big heating element inside that consumes alot of power in order to start the flames in the flutes." Is this correct?
Electric cooking appliances
1 Microwave/oven combo
= 10200 Should I not take from table 220.55, column C, 1 appliance = 8000?

His calculations come to 130AMP load, and I have 100AMP service. My calculations brings me to 106AMP, so I'm still over, but if I'm right I'd understand how to tweak my appliances (like that disposal that can turn chicken bones to dust

Thanks in advance for any help.

I come up with 92 amps using the optional method, and

98 amps using the standard method.

 

[kwired]

House I once lived in had more loads then you mentioned and never tripped the 100 amp main FWIW.

A/C was only 2.5 ton, but also had electric water heater, electric dryer, electric range and some electric space heating (don't know if heating or cooling load was larger)

If only making kitchen changes, I wouldn't be too concerned unless adding a lot of load that wasn't there before.

 

[evdryst]

I need to do the best I can with the 100 amp service. It's all dandy to say it will be enough and I appreciate the reassurance, but I need to get it past the inspector.

Dennis Alwon, would you mind explaining why I can't use column C, 1 appliance = 8000 for the oven?

David Luchini, how did you manage that? Do you have something scribbled on a napkin I can have? My email is {The email address has been removed by a moderator. Use Private Messaging to contact this member.}

Thanks all.

 

[growler]

I need to do the best I can with the 100 amp service. It's all dandy to say it will be enough and I appreciate the reassurance, but I need to get it past the inspector.

Dennis Alwon, would you mind explaining why I can't use column C, 1 appliance = 8000 for the oven?

Is that microwave/oven combo the load that you are adding for the kitchen remodel ?

I see a lot of remodels where they change from gas to electric on the water heater and range and this can put the calcualtion over a 100 amps in many cases.

Does the jurisdiction allow the optional method of calculation to be used because this number will normally be smaller.

 

[david luchini]

I need to do the best I can with the 100 amp service. It's all dandy to say it will be enough and I appreciate the reassurance, but I need to get it past the inspector.

Dennis Alwon, would you mind explaining why I can't use column C, 1 appliance = 8000 for the oven?

David Luchini, how did you manage that? Do you have something scribbled on a napkin I can have? My email is {The email address has been removed by a moderator. Use Private Messaging to contact this member.}

Thanks all.

Lighting, small appliance, & laundry = 10350va...demand = 5573
Appliances = 4563 ..........................................demand = 3422 (I left out fridge, could probably leave out freezer, as it is included in small appliance load.)
Range.........................................................................= 8000
A/C.............................................................................= 6500

Total = 23495 = 98A @ 240V

 

[charlie b]

I tend to be skeptical when I hear or see someone make a statement along the lines of, “I can’t do that because it’s against the rules.” May I ask exactly how you came to believe that the HOA would not allow you to increase your service to 200 amps? Did you submit an application to the HOA and did they turn it down? I can’t imagine that the HOA contract has a line item that says, “Your electric service is, and shall remain, 100 amps, and you are not permitted to increase it.” So let’s set aside anything that anyone told you, and let me ask this: Have you personally seen, in writing, a statement to the effect that the HOA will not permit any service upgrades?