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Amp difference for 'up-to-date' Window Air Condition, what procedure needs for?

Amp difference for 'up-to-date' Window Air Condition, what procedure needs for?

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  #1  
Old 05-19-15, 10:24 AM
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Amp difference for 'up-to-date' Window Air Condition, what procedure needs for?

Hello:
I tried to upgrade one of old Window Air Conditions (using 220 amp?) to an 'up-to-date Window Air Condition (using 110 amp)' at Lowe's.

The problem is that an exiting Air Condition was installed more than 15 - 20 years ago and the '3 prone receptacle' of an up-to-date Window Air Condition/12,000 BUT' is NOT like the one we've been using for Window Air Condition for many years.

What type of electrical work needed to be done, ..... like re-wiring climbing up an attic or what procedure does an electrician need to work on?

Is this to be 'expensive job?'

Thanks for your help in advance.
 
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Old 05-19-15, 10:33 AM
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First it's voltage -- the old air conditioner is 240 volts; the new one is 120 volts. It is probably a simple conversion which can re-use the existing wiring, but we would need to know what the existing wiring is to confirm that. We would also need to know what size is the existing breaker and what type of plug is on the new air conditioner.
 
  #3  
Old 05-19-15, 02:07 PM
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Hi PineCone,

Your old Air Conditioner used 240Volts, if back then was properly wired it means that at the Breaker Panel there should be installed a Double Pole Breaker for that circuit, and that your old AC Outlet must be *at least 30Amps* (*CORRECTION*: *It could also be a 6-15 or 6-20 240VAC outlets*) having up to 2 Hot wires, 1 Neutral wire and 1 Ground wire (optional in some 240v circuits) connected... said that, the simple, easiest way to proceed is to change your old 240Volts Outlet for a 20Amp Outlet (120v) using old wiring, ONLY connecting 1 Hot, 1 Neutral and 1 Ground to the new outlet; and also removing the Double Pole Breaker that serves that circuit at the Breaker Panel and replace it for a 20Amp Single Pole Breaker (120v), connecting just 1 Hot Wire at the New 20Amp Single Pole Breaker; meaning that you can left the other Hot Wire of your old 240v circuit abandoned, as long as you disconnect that hot wire from both sides at the Breaker Panel and at the new installed outlet. That way you don't have to change your old wiring at all.

WARNING: My recommendation is based ONLY in the case your old 240v circuit that serves your old Air Conditioner IS A DEDICATED CIRCUIT. BUT in the case that the same circuit serves other 240v devices, then you CAN'T changed it to 120v. In such case running A New Dedicated 20Amp 120v circuit for your new air conditioner will be the best way to proceed.


Thanks a lot.


Jos
 

Last edited by JosiQDIY2015; 05-19-15 at 02:52 PM. Reason: Spelling: Changed Air Conditioning for Air Conditioner
  #4  
Old 05-19-15, 02:20 PM
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Hi ibpooks,

We would also need to know what size is the existing breaker and what type of plug is on the new air conditioner.
All up to date 120Volts Window Air Conditioners ***THAT ARE 120Volts*** at Hardware Stores in U.S. all of them those that are 120Volts use a 5-15P plug, so a standard 20Amp even a 15Amp Outlet will support his new Air Conditioner plug.

Regarding the existing size breaker, we can deduct he have currently a Double Pole Breaker because his old Air Conditioner was running on a 240Volts Outlet.
 

Last edited by JosiQDIY2015; 05-19-15 at 03:25 PM. Reason: *Correction in Sentence*
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Old 05-19-15, 02:47 PM
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All up to date Window Air Conditioners 120Volts at Hardware Stores in U.S.
Not sure what you base that on. They still make and sell 240 A/Cs.
The problem is that an exiting Air Condition was installed more than 15 - 20 years ago and the '3 prone receptacle' of an up-to-date Window Air Condition/12,000 BUT' is NOT like the one we've been using for Window Air Condition for many years.
Not true. A/Cs larger then 15000 BTUs are still usually 240 volts and use that plug and receptacle. You are probably going back with a smaller A/C if it is 120 volts. Are you sure it will cool the area.

To summarize the voltage of A/Cs depends on BTUs and if they have a heating setting. The voltage requirements have not changed over the years. Past a certain number of BTUs the amp requirement is to great for a 120 volt circuit. The manufactures usually size the 120 units to work on a 15 amp circuit with enough left over capacity to handle starting and a couple of unrelated additional light loads.
 
  #6  
Old 05-19-15, 02:59 PM
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Hi ray2047,

Please read my entire sentence. I never said that all Air Conditioners at Hardware Stores in U.S. are 120Volts only. I said that THOSE THAT ARE 120Volts only use 5-15p plugs. Of course they sell 240Volts Air Conditioners too in all Hardware Stores in U.S. and THOSE THAT ARE 240Volts use 6-15p plugs.


Thank you.

Jos
 
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Old 05-19-15, 03:02 PM
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Sorry I misread your post.
 
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Old 05-19-15, 03:16 PM
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Don't worry, it was my mistake I forgot to be more specific in the terms. I already corrected the sentence at the post.


Most Modern Window Air Conditioners:

120Volts use 5-15 or 5-20 plugs depending on amperage.

240Volts use 6-15 or 6-20 plugs depending on amperage.


And about Amperage Usage:

These days most of Window Air Conditioners use less than 20 Amps. I have researched up to 25,000BTU 240Volts and use less than 20Amps, most of them using less than 15Amps.


Thank you.


Jos
 
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Old 05-19-15, 03:36 PM
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I have researched up to 25,000BTU 240Volts and use less than 20Amps
Yes and that is why they use 240. At 120 you would be looking a double the amps. But I believe we have gone off topic here. The real questions are if PineCone bought a large enough A/C and how to convert the circuit to 120 volts.
 
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