# Load calculations on a church



## five.five-six (Apr 9, 2013)

My son’s Boy Scout troop is sponsored by a church. The church burned down and now they are holding services in a 100 year old historical landmark church on the property until the burnt up church gets rebuilt. 

I was approached by a board member to supply electrical to some AC they want to install in the 100 year old sanctuary while the other church is getting fixed. They have a quote for 3 each 2 ton units and 1 ea 5 ton unit.

The problem is that the meter socket is on another building and it’s only 200A and there’s only 3/0 wire to the 200 and 125 sub panels in the historical church. 

This is a little outside my wheelhouse, I could use some direction in calculating the maximum load I can add to the system.


I already walked the entire building and noted nameplate specs and took lighting counts. And have a rough estimate of 9,500 Sq Ft

TIA


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## MikeFL (Apr 16, 2016)

You need to give us the other loads that are in there, and which panels they come from.

Draw up a sketch showing us service, conductor size & length, panels, etc.

Then give us an existing panel schedule for each panel so we can see what's on there.

Then give us load specs on the new equipment.


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## five.five-six (Apr 9, 2013)

I spoke with an EE I have used over the years for on occasion and he told me that as a commercial space, the church is required 3W/sqfr the 11 tons going to be about 115A as continuous duty load...basically, there’s just no way for it to get past plancheck without a variance.


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## CoolWill (Jan 5, 2019)

I was involved in a similar situation. We were able to connect the A/C units to a temporary service set just for that purpose.


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## Cow (Jan 16, 2008)

One thing you can do for real world load info is contact the utility co. with the meter number and ask them for the peak demand over the last 12 mos. This is assuming they have a smart meter installed.


If you get this info in an email from the power co, you can show the inspector. That's what we do.


Then add in your HVAC units and see where you end up.

A paper load calc based on an NEC mandated 3w/sq ft isn't exactly real world.


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