Do these numbers seem right? Heat load calc

[sayed]

First time working on this type of calc, just looking for input from someone who is used to doing heat load calcs

The cooling requirement seems incredible high to me. Is this right? ~45ton of cooling needed? This is for a <5000sqft building used as a nightclub with occupant load of 290.

I've going through the building code and meticulously reviewing all my input. Just seems really high to me, but i am not sure if this is typical of a nightclub


 

Walls



Loss

10169



Sensible Gain

3962



Latent Gain

0



Windows



1310



1505



0



Doors                                                          



5479



5822



0



             Ceiling                                     



3556



2540



0



Skylights



0



0



0



Floors                                                       



0



0



0



Room Internal Loads



0



84537



95485



Blower Load






1707



0



Hot Water Piping Load






0



0



Winter Humidification Load



0



0



0



Infiltration



0



0



0



Ventilation



176792



94710



249805



Supply Duct EHLF=0 ESGF=0



0



0



n/a



Return Duct  EHLF=0 ESGF=0



0



0



0



Subtotal



197306



194783



345290







Total Heating



197306 Btuh









Total Cooling



540073 Btuh

 

[sayed]

I used a design time of 6:00pm and the tonnage came down to 34. 

Someone said to use this since it is a nightclub, but now that means there could never be 290 occupants for a meeting/presentation/party that takes place at 12:00pm as the system couldn't handle it.

 

[namod65]

A nightclub is a great example for HVAC engineers just learning load calcs, because it clearly shows how much the people and ventilation drive the cooling load. 290 seems like a believable occupant number for 5000 SF nightclub. 290 people in a nightclub setting are going to be such a high load that rest of the factors will be peanuts compared to it. Time of day to pick solar exposures shouldn't even matter here. Look at your numbers: your people load + ventilation (84537+95485+94710+249805 = 524537 BTUH) is 44 tons. Your walls/roof/doors/glass is only about 1 ton total. So whenever the building is loaded up to occupancy, you're going to need the 44 tons regardless of the time of day.

Now to look more closely at your numbers: I think your latent load for people is a little low. Since this is a nightclub, people will be dancing and getting sweaty. My load calc software would use 545 BTUH of latent per person which would drive your load up some. Next your ventilation latent load seems high, it's more than double your sensible. What outdoor design conditions did you use?

But to answer your question, assuming the space is 5000 SF, and you have 45 tons. That comes to about 111 SF/Ton, which I don't think sounds outrageous at all for a bar/nightclub. Those places get hot!

 

[MetsFan]

A nightclub is a great example for HVAC engineers just learning load calcs, because it clearly shows how much the people and ventilation drive the cooling load. 290 seems like a believable occupant number for 5000 SF nightclub. 290 people in a nightclub setting are going to be such a high load that rest of the factors will be peanuts compared to it. Time of day to pick solar exposures shouldn't even matter here. Look at your numbers: your people load + ventilation (84537+95485+94710+249805 = 524537 BTUH) is 44 tons. Your walls/roof/doors/glass is only about 1 ton total. So whenever the building is loaded up to occupancy, you're going to need the 44 tons regardless of the time of day.

Now to look more closely at your numbers: I think your latent load for people is a little low. Since this is a nightclub, people will be dancing and getting sweaty. My load calc software would use 545 BTUH of latent per person which would drive your load up some. Next your ventilation latent load seems high, it's more than double your sensible. What outdoor design conditions did you use?

But to answer your question, assuming the space is 5000 SF, and you have 45 tons. That comes to about 111 SF/Ton, which I don't think sounds outrageous at all for a bar/nightclub. Those places get hot!

Agreed, and nice breakdown!  I took a look at my Carrier quick reference manual and they show 100 SF/ton for bars / taverns (closest to a night club they have) so 111 SF / Ton doesn't seem unreasonable.

 

[Audi Driver P.E.]

Without even looking at your calculations or numbers I can tell you, you are in the right ball park (maybe on the low side depending on location), and I'm not an HVAC guy.