hotel load calculation

[bwyllie]

This question seems to be coming up in various scenarios but I am trying to understand the hotel room load calculation. Do I take 2w/sf for the hotel rooms and then apply the demand factors from 220.42(refrig and bath room are included in the 2w/sf, i believe 220.14(J)(1) answers for the bathroom, I am not clear if a refrigerator is included in the 2w/sf) or do I need to add the load of the refrigerator and bathroom circuit for the hotel room to the 2w/sf and then apply the demand factor. HVAC is at 100%.

Thanks

 

[George Stolz]

What an excellent question! I have been looking around for at least 20 minutes now, and now am getting sleepy. So, forgive me if this makes no sense.

Do I take 2w/sf for the hotel rooms and then apply the demand factors from 220.42(refrig and bath room are included in the 2w/sf, i believe 220.14(J)(1) answers for the bathroom...

I would say this way is wrong, IMO.

...or do I need to add the load of the refrigerator and bathroom circuit for the hotel room to the 2w/sf and then apply the demand factor.

Here's how I see it: I look at 210.60(A).

210.60 Guest Rooms or Guest Suites. (A) General. Guest rooms or guest suites in hotels, motels, and similar occupancies shall have receptacle outlets installed in accordance with 210.52(A) and 210.52(D).

So, hell or high water, guest rooms are required to have wall space receptacles and bathroom receptacles. Small Appliance Branch Circuits are not required as a minimum.

These are covered by 220.14(J)(1), as you indicated. Now that these are locked in as givens, lets move on, and continue with 210.60:

Guest rooms or guest suites provided with permanent provisions for cooking shall have receptacle outlets installed in accordance with all of the applicable rules in 210.52.

So if they can cook, suddenly (B) and (C) (and the others) kick in. Now we have Small Appliance Branch Circuits (SABCs) to add in per 220.52(A). The refrigerator is covered in the pair of 1500VA SABCs per unit.

So, that tells me that prior to having cooking equipment, you must treat refrigerators as appliances, to be dealt with as outlined in 220.14(A). I do not see any demand factors for fridges in hotels, so I would say officially you could be required to take these loads at 100%. In the same breath, I'd say any AHJ would probably allow you to use the 75% factor provided in 220.53.

What do you think?

 

[bwyllie]

I think that sounds reasonable, however I am a little hesitatant on using 220.53 because that applies to a dwelling unit and I am not considering each hotel room a dwelling unit because there is no provision for cooking in the rooms.

 

[George Stolz]

You might consider (as an engineer) to try to divine some "load diversity", if you're looking to whittle away some amps.

I don't see all the refrigerators running at the same time. But, it would likely be a superior design if the fridges are taken at 100%.

 

[bwyllie]

thanks for the input, trying to reuse a 200A feeder, I am sure in the "real world usage" it will be fine but need to make sure the numbers add up correctly by the Code.

 

[George Stolz]

What are you coming up with?

 

[bwyllie]

let me get back to you in a few days, I am out of the office and all the exact numbers are in my folder...in the office!

 

[bwyllie]

15 rooms per floor and 200Amp feeder at 208V, three-phase serves 3 floors.

12,000SFx2w/sf=24,000VA
Based upon demand of 220.42: 11.6kVA

Refrigerator in each room, .3kva x 45 = 13.5kva

HVAC units 1kva x 45= 45 kva

Total kva= 70.1kva or 194.5Amps

 

[wirenut1980]

I think that sounds reasonable, however I am a little hesitatant on using 220.53 because that applies to a dwelling unit and I am not considering each hotel room a dwelling unit because there is no provision for cooking in the rooms.

Since you are hesitant to call it a dwelling unit for that instance, you could try 220.56, which would allow 65%. I agree with your 100% for the HVAC units and am wondering if those might be considered continuous loads...depending on where job is located I guess.