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The panel is on the other side of the wall (outside) so I would have to embed the wiring in the wall.

I'll call my landlord on Monday and ask if I could add a 20A outlet, with written approval and ensure it's done by a licensed electrician. -Thanks

Hopefully this works out and I could plug the 1250W and cooling unit to the 20A outlet, then the rest of the lighter devices on the existing 15A outlets.
Don't have your 1250 watt device and the cooling unit plugged into the same circuit. The starting amp draw of the cooling unit will probably be too much for the circuit, and trip the breaker.
 

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Hopefully this works out and I could plug the 1250W and cooling unit to the 20A outlet, then the rest of the lighter devices on the existing 15A outlets.
No way. Whatever cooling unit you have will definitely need its own circuit, or at least a circuit that doesn't already have over a kilowatt on it. Cooling requires a LOT of power. Figure that the cooling load will be about 20% of the servers' total power consumption. In other words, if you put 2000W of heat into the room it will take about another 400W to cool it. More if it's hot outside. That's the average power consumption for cooling, so if the AC is sized to run about half the time (which it should be) then you'll be pulling close to 1000W when it's on.
 

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Also, is there a limit on power usage for all circuits combined?

My a/c, washer, dryer, water heater, kitchen appliances, etc are all on their own circuits, but does running them all at the same time have any affect on my electrical line?

I was just imagining a hot summer weekend where we're washing clothes and cooking up lunch and the servers are running.
Yes there is. What ever the main breaker is listed for, is the max total draw per leg.
 

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You guys are looking at the cooling situation all wrong. Keeping the room cool with an ac unit is going to be in the 1000 dollar a month for electicity range between the computer and hvac. The way to go about it is to build an enclosure at the window so cool air is sucked through the house, runs through the computer and the hot air is exhausted out the window.
 

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You guys are looking at the cooling situation all wrong. Keeping the room cool with an ac unit is going to be in the 1000 dollar a month for electicity range between the computer and hvac. The way to go about it is to build an enclosure at the window so cool air is sucked through the house, runs through the computer and the hot air is exhausted out the window.
Pretty sure he said he lives in Arizona, so he won't have cool air to draw in through the window.
 

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Pretty sure he said he lives in Arizona, so he won't have cool air to draw in through the window.
That's why I didn't suggest that. I said exhaust out the window. Suck cool air from the living room. It will make the heat pump work a little harder, but nothing compared to exhausting 1500 watts of heat into the house and then trying to cool it back off
 

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That's why I didn't suggest that. I said exhaust out the window. Suck cool air from the living room. It will make the heat pump work a little harder, but nothing compared to exhausting 1500 watts of heat into the house and then trying to cool it back off
Same difference. Since the A/C for the house will have to run longer to cool all the fresh air pulled into the house by the fan exhausting air out of that window.

Can't blow air out of a window, without fresh air coming back into the house, which will need to be cooled down, and be harder to cool then the heated air from the electronic equipment.

A window A/C for that room won't have to run too much. Since the room will still get A/C from the central system.
 

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Same difference. Since the A/C for the house will have to run longer to cool all the fresh air pulled into the house by the fan exhausting air out of that window.

Can't blow air out of a window, without fresh air coming back into the house, which will need to be cooled down, and be harder to cool then the heated air from the electronic equipment.

A window A/C for that room won't have to run too much. Since the room will still get A/C from the central system.
Depends which is hotter. The computer without the case fans going or the outside temperature. If its 90 outside and the computer is 130 without any fresh air its more efficient to exhaust outside. A cpu runs in the 200 degree range with exhaust fans going. This one is going to run even hotter. A window ac unit would run 100% of the time and still be 90 degrees in the room. Doesn't sound efficient to me. He said he wants to run 3 computers and we aren't talking about little dell pcs sitting idle in sleep mode
 

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Depends which is hotter. The computer without the case fans going or the outside temperature. If its 90 outside and the computer is 130 without any fresh air its more efficient to exhaust outside. A cpu runs in the 200 degree range with exhaust fans going. This one is going to run even hotter. A window ac unit would run 100% of the time and still be 90 degrees in the room. Doesn't sound efficient to me. He said he wants to run 3 computers and we aren't talking about little dell pcs sitting idle in sleep mode
He already said his wattage is 1760. Thats just over 6000 BTUs. He'll have his central A/C also running, so the window unit won't be doing all the work. In reality, he'll only need a 5000 BTU window unit to keep the room at 80. And thats only 500 watts of electric consumption on standard efficiency window units. So about 362KWHs a month if it ever ran 24/7 to keep the room cool enough for the equipment.
 

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He already said his wattage is 1760. Thats just over 6000 BTUs. He'll have his central A/C also running, so the window unit won't be doing all the work. In reality, he'll only need a 5000 BTU window unit to keep the room at 80. And thats only 500 watts of electric consumption on standard efficiency window units. So about 362KWHs a month if it ever ran 24/7 to keep the room cool enough for the equipment.
Im not too familiar with ac units, since most people don't have ac in my part of the country, but that doesnt add up to me. How is 500 watts of ac going to offset 1700watts of heat?
 

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Jimmy21,
Without getting into the thermodynamic details, it's easier to move heat from point A to point B then it is to create heat. Thus the AC can be sized smaller than the heat generator. To get energy star rating an AC unit needs to move ~3.2 units of energy to the outdoors for every unit of input energy (assuming outdoor temp of 95F and an indoor temp of 80F).

If you're curious, here's how I came up with the 3.2 number:
- Energy Star requires AC units to have an Energy Efficiency Ratio of 11 (or 12 depending on the type of unit)
- EER is in the oh so helpful units of (BtuH/Watt)
- Wikipedia has the formula for the conversion from EER to the Coefficient of Performance (COP)
- COP is in the helpful units of (Energy Removed / Energy In)
- The formula is EER = COP * 3.412
- Thus ACs need a COP of 3.22 (or 3.52 for certain types) for an energy star rating
 

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Depends which is hotter. The computer without the case fans going or the outside temperature. If its 90 outside and the computer is 130 without any fresh air its more efficient to exhaust outside. A cpu runs in the 200 degree range with exhaust fans going. This one is going to run even hotter. A window ac unit would run 100% of the time and still be 90 degrees in the room. Doesn't sound efficient to me. He said he wants to run 3 computers and we aren't talking about little dell pcs sitting idle in sleep mode
I'm in Phoenix. It was almost 90 yesterday. Drawing ambient air for cooling in Arizona only works about 4 months of the year. Daily peak ambient air temperature in urban areas over asphalt can reach 120-130 degrees for 3 months straight. We use heat exchangers for make-up and exhaust air here the same way people in very cold climates do, but the other half of the year. There's no way around it - if you want cool electronics in Arizona, you have to pay to move the heat.
 

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Im not too familiar with ac units, since most people don't have ac in my part of the country, but that doesnt add up to me. How is 500 watts of ac going to offset 1700watts of heat?
The average window A/C will remove 10 BTUs of heat, for every watt of electric they use. So a window unit that is consuming 500 watts, is removing 5000 BTUs of heat.

As above, it takes less energy to move heat, then it does to generate it. And all an A/C does is move heat from one place to another.
 
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