load calcs

[stew]

my load calc skills are way rusty. need some guidance. office spaces which are now to be remodeled with no load change. 1028 sq ft. hvac loads are 3 ton pumps @ 28 a 208 v single phase w 60 amp elec heat back up. the only other loads are bath exhuast fan lite combos.thes now have 125 amp 3 phase 120/208 volt feeds. They may not even require load calcs on this as it is fire damage repair in like kind with no load change but I want to be prepared if I am asked to supply a calc. the heat does not run when the heat pump runs which is what I am not sure how to treat.

 

[stew]

is this the wrong place to post this or does anyone want to take a shot at this? still have not been able to determine exactly how to count the hvac and or furnace load as they do not of course run at the same time. it would seem tro me that the highest load would be used and disregard the lowest. use the heat strip load but not the hvac.

 

[Chamuit]

On heating and cooling, you use the higher of the two loads. If you have one unit doing both, it should be on the nameplate. If you have two seperate units you'll have to go to both to find that out.

I think I'd wait and see what the AHJ wants or ask what they want.

 

[e57]

is this the wrong place to post this or does anyone want to take a shot at this? still have not been able to determine exactly how to count the hvac and or furnace load as they do not of course run at the same time. it would seem tro me that the highest load would be used and disregard the lowest. use the heat strip load but not the hvac.

Been sorta slow 'round here today - and doubt anyone really wants to jump through a hoop to do a load calc - but some might????

Anyway - there are some decent examples in Annex D outlining heating vs air conditioning however they all apply to Dwellings.... :roll: In your case I would look toward 220.60.

 

[stew]

220.60 does it for me. thanks