Wanting to upgrade electric panel. Do electric companies care?

Growroom Design
#1

I wanted to install central air/heating system and did some calculations from a website that listed my total amps at 165A.

It looks like a 200A service would be needed, but I worry this may draw red flags as to why a house would need such a big service.

This is how I came up with my figure.

2000sq. ft. house x 3 = 6000w for receptacle and lights
20A dishwasher = 2400w
50A range 220v = 11000w
20A kitchen = 2400w
20A washer = 2400w
30A dryer 220v = 6600w

Total 30,800w. Subtract 10k that will be calculated at 100% and do 20,800w x 0.4 then add 10k back to get 18,320w.

60A for home heating/cooling unit at 220v = 13,200w
20A room 1
20A room 2
15A shared between them = 6600w I’m calculating this at 100%

Total 38,120w divided by 230 = 165A

Grow related circuits aside I’m at 137A and I like the wiggle room in case I wanted to add say a hot tub. I guess I could argue that?

This is all under the assumption they even ask why.

I do not plan on doing this myself, but will hire out a licensed electrician.

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#2

200a services are actually quite common and the norm for new builds and houses these day, I’d have zero concern

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#3

Agree, 200A is a common upgrade today.

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#4

In my experience the electric companies don’t care as long as you’re not stealing power and are paying your bills. I had the smallest house on a block and the highest electric bill, no one batted an eye…
I wouldn’t be concerned at all especially since you’re installing an ac…

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#5

ive had 200 amp service running for a few years now, no issues. stay current with your bill and the power company doesnt have any reason to care what you do

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#6

There’s guys here in town with $1000 monthly bills, you’ll be fine. Worry about plant counts, nosy neighbors, and smell, don’t worry about “too much power”, as long as it’s safely wired.

Power companies love home growers. Consumers like us pay a higher rate per watt than their commercial customers, and we almost always pay on time.

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#7

That 60A number you have for heating/cooling unit is dubious. A 2 ton a/c unit (avg for 2400 sq’ home) draws 50A (requires 25A tandem breaker) on startup and only consumes 10A or so (2KW) when running. My 1-1/2 ton unit is on a 20A tandem breaker and draws about 8A when running fully loaded. Our house is a 4 bedroom, 2000sq’ 2 story.

#8

Thats a wicked undersized unit. 1 ton of cooling is good for 400-600sq. ft. Depending on where you live.

Maybe 60A is a stretch. I was looking at a 4 ton unit

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#9

Actually, it’s not. Our house was built in the early 1980’s and it’s fairly well insulated. It’s not that well sealed though, which can cause issues on windy days both during heating and cooling seasons. Here in SW Ontario it can get very humid in the summer. We keep the house at 75f during the summer months and find it very comfortable. If it got much hotter here in the summer (it’s coming) I would want a larger system. Going with a smaller system versus larger allows for better dehumidifying, and given my choice between drier and warmer versus cooler and damp, I’ll take dry. A larger system would cycle on and off more frequently and leave the house more humid.

I suppose that a 400-600 sq ft uninsulated building may require a ton, and as you say depending on where you live. A 4 ton central a/c unit needs to be on a 100A (50A tandem) breaker to allow for start-up current and should run at around 20-25A @ 230V.

We had a house a few years back that had an oversized a/c unit (1800 sq ft bungalow with 2-1/2 tons) and it was horribly uncomfortable. Felt like we were living a cave. I had to pull every trick in the book to get that a/c unit to do a decent job of dehumidifying to keep the place comfortable.

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#10

If it works it works. Everything matters though. Wall construction, direction of walls, how many linear footage of window and door edges. I used to work for a mechanical engineer doing load calculations through a program and those were all the inputs. I know in the commercial world we do 400 sq. ft. per ton.

I actually contacted the Mitsubishi rep in my area and that’s the size they recommended was a 3 ton hyper heat with inverter tech. 76% at -13F 100% at 23F. Decent system for the price.

The AC market is constantly evolving and there are systems like VRF and hyper heat that are very efficient. Heat recovery VRF are invaluable to the home grower as the system can extract heat from the grow rooms and distribute to the rest of the indoor units.

There is also technology that makes the units not just turn on and off, but run at reduced capacity to save electricity when a full load isn’t needed.

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#11

I could see that. I worked in a 1.2M sq/ft office building that had 2 - 730 ton (Trane) heat reclaim and 1 730 ton (straight) liquid chillers in the early 80’s. With 2 machines running we rarely topped 70% load. Of course that’s ancient history (30+ years ago), and back before every desk had a pc sitting on it.

I’m not convinced that all of the fancy bells and whistles available with modern systems are worth the investment in a residential environment. They look great on paper, but is your home any more comfortable?

#12

A 2 ton in a 2400 square foot home is standard size here in Southern Ontario. Some installers will run a 2.5 ton coil for better humidity control and efficiency.

I remember playing with those old BTU calculations programs the only thing I took away from it was 1 ton = 12000 BTUs and a 1000 watt hid system generated 4000 BTUs

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