In this part of the label, you get told just how many amps will be pulled when you initially start your compressors motor. You can get all this AC wire sizing information from this chart. The circuit breaker requirements for central air conditioning systems vary widely depending on the units size. You can often find exact requirements for breaker size printed on your mini-split compressor unit. Most of the time, youll find a window unit set in a window opening and plugged into a regular 110V/120V outlet. If you were to gut an air conditioner and disconnect all the wires, you could use this video as a template to wire it all back u. An average 4-ton AC unit has a max. As much as I wanted to help, the OP sounded like he thought it needed 4 circuits! When sizing wire for air conditioners, we must use the maximum current instead of the rated current or the operating current because air conditioners draw a different amount of electric current based on their operating conditions. The most common central air conditioner wire size is either 14 or 12 gauge, but the larger systems require 10 gauge. Two HVAC contractors who have 30+ years experience want the homeowner to install the electrical wiring! You might want to take the tour so you'll know how to best participate here. Email: [emailprotected]Chat: LinkedIn Message, AboutPrivacy PolicyTerms and ConditionsImpact ReportSubscribe, eBooksCalculatorsTemplatesCoursesConsultation. The BTU ratings are also listed here, if that is how you are trying to determine the wiring size. We have 1-ton, 2-ton, 3-ton, 4-ton AC units, and so on, that run on 220V circuit (smaller below 1.5-ton units run on 110/120V circuits). Find the wire size you need on the charts above. When most central air conditioners first start up, they may require up to 5,000 watts of electricity. Different contractors may also know what the inspectors like to see- so if they're expecting to see a 10 gauge wire (30A), and the contractor installs 12 gauge (20A), they'll get burned. A 220V 15A socket can deliver 3.3kW, and even if the voltage drops to 180V it can still do 2.7kW. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. You need to use breaker recommended on unit tag. Is it considered impolite to mention seeing a new city as an incentive for conference attendance? If the wire is not sized properly it will be come a load. I forgot to mention that the run is only about 30-35 ft. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Recommended R-Values For Attic, Return Duct Size For 2, 2.5, 3, 3.5, 4 And 5 Ton Units, How Much Freon In 2, 2.5, 3, 3.5, 4, 5, 6 Ton Units? When looking at the label itself, only about nine of those labels may be of any use, assuming you are not a certified electrician anyway. Unless the HVAC has written in the contract that he will hire and supervise the electrician and include that in the job. It appears they have no intention to apply for permits. FYI: mine is a 2.5 ton, replaced a 2 ton using the same circuit. Wish we could have helped but in this case, he needs a pro. What size wire for 2 ton air conditioner? If we apply the same NEC 80% rule for our 10 amp AC unit, Breaker Size = 10 amp 100/80. You could go with larger wire (10 gauge), but not smaller (14 gauge). sktn77a - Nope.thats exactly the instructions they each gave and is written on the estimate. A regular heat pump requires two dedicated branch circuits: the condensing or AC unit and the air handler. Overload is one of the many possibilities if you dont utilize the proper wire size, and incompatibility issues can be just as obvious. That means you will need to use a 10 AWG wire with 35A ampacity. For all these reasons and more, youd want to adhere to a measure twice, cut once mentality, especially when safety and financial stability are the cost. In return, it makes it much easier to determine what size breaker you need. You should ask the contractors about that. If it says 34 amps, like in the example below, we need 8-gauge wire. Using a higher gauge wire for an air conditioner or heat pump can be catastrophic, and you should avoid making this mistake at all costs. Let us break it down for you before we go any further. There is a disconnect 2 ft from the condenser and its all on its own double pole breaker. Most mini-split units run on 220V or the equivalent. PICKHVAC Terms of Use: Some of the products seen on our site are delivered through a relationship with outside suppliers like Networx.com, Google, and others. But a lot of it has to come straight from the wiring. Regarding heat, one ton equals 11,917 British Thermal Units (BTU) per hour, often rounded to 12,000 BTU/hour. Low noise operation and high efficiency. required amps, you have to consult. A disconnect box to be mounted outside the house within a few feet of the condenser location. Needless to say, it is critical to run air conditioners with correct wire sizes. Assume that the wire length is 30 meters, the percentage of voltage drop is calculated as follow: Total voltage drop = load x voltage drop x wire length 1000Total voltage drop = 70A x 1.55 MV/A/m x 30 meters 1000Total voltage drop = 3.255V, Voltage drop % = 3.255V 415V x 100Voltage drop % = 0.78%. The model number allows us to glean the cooling capacity of this particular heat pump by using two specific numbers located in the middle of this string of numbers. But in those case of 120 volt loads you mention, the wire matches the breaker. We and our partners use cookies to Store and/or access information on a device. Here your labeling will tell you whether or not the unit you are looking at is an AC, or its slightly more energy-efficient cousin, the heat pump. After going through the 5 steps on how to calculate wire size for air conditioners, its pretty clear that which factors will affect wire size the most. The cost difference between 10 gauge and 12 gauge is minimal, especially for short runs (other than being more difficult to bend). What Size Wire for Central Air Conditioner? Will 10-2 wires work on the central air conditioner? (Calculated), Best 5 Zone Mini Split Systems In 2023 (Mitsubishi, Carrier, etc. For most people, using the following wire size chart should be sufficient. Probably not necessary, but that doesn't mean it wouldn't be a better idea. We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. Based on the above chart, this 3-ton air conditioner unit requires an 8-gauge wire and a maximum size of 35 amp circuit breaker. Below well take a closer look at the different types of ACs, and heat pumps to help you choose the correct breaker and wire size. The first step to calculating wire size is to identify the load in terms of electric current. Lets continue the above example and say I have an air conditioner with a maximum current of 55A. Since tags provide a lot of information, you may be wondering if the breaker size is on it in the first place. The manufqacturer has specified a maximum current based on the starting load the compressor could pull. What If You Dont Use the Correct Size Breaker or Wire? Info tip: At the circuit breaker box, the important issue of preventing damage to the wiring and the system in general is addressed. The amperage should not be greater than 80% capacity. For instance, a 5 ton ac needs 2.5mm2 or 14-gauge wire to safely operate given that its maximum current can go up to 15 amps. Mega Kabel wire current-carrying capacity table, https://aircondlounge.com/category/buyer-guide/. While it may seem unimportant initially, the number itself is needed to know just how much electricity you would need to run your entire system off of a generator should the need arise. I agree d.george. The correct wire size for any central air conditioner is not determined by voltages, but by the cooling capacity of the system. What size breaker for a central air conditioner? Residential AC Unit Replacement - BRYANT Feedback pls? With correct wiring and the right wire size, it is assured that the air conditioner is safe to operate. The basement is low - 7ft maybe - and with pipes they are a tight fit, so I get it if they're afraid of damaging them. Building-Center.org is a good resource for determining the age of your HVAC and other mechanical equipment. So, you could get by with a 30 amp breaker. NEC (National Electric Code) recommended that voltage drop should not exceed 5%. As we mentioned previously, it truly depends on the heat pump size. The minimum ampacity helps determine the minimum gauge wire you need to use. Yes. Check them out if youre looking to buy one. Wire is supposed to be sized at 125% of the full load amperage shown on the appropriate chart. Below is a quick reference table to help you decide what wire gauge is best for your situation based on your circuit breaker size:Breaker Size (Amps)Aluminum Wire Size (AWG)Copper Wire Size (AWG)15#12#1420#10#1230#8#1040#6#850#6#860#4#6. However, one might wonder how many amp breakers you need for a heat pump. 2.5 ton: In the case of a 2.5-ton AC, the size of the breaker will increase. You probably do not want the cheapest bid, especially if it's by a margin. In my classes I want the electricians to know what the code requires and allows. Still, the most notable of them would be that most manufacturers offer the manufactured year your condenser here. Window air conditioners and heat pumps can typically manage up to 500 square feet and range from 0.5 tons (6,000 BTU/hour) to 1 ton (12,000 BTU/hour). Most large air conditioning units and heat pumps run on 220V and require their circuit with a double-pole circuit breaker. Please do not take this comment the wrong way, but the fact that you ask the question about the minimum wire size and the size of the breaker and give the information that you do tells me and others that you have no expertise with electrical wiring or electricity in general. Tankless Water Heater Breaker Size Calculator: What Size Breaker? Breaker Size = 12.5 amp. Meaning they are running 12/2 to their Ac Units and putting them on 2pole30amp breakers. You can use a breaker with more capacity than you need, of course. Small mini-split systems and window units often require a 15 amp breaker, so a 12-gauge aluminum wire or a 14-gauge copper wire is usually suitable. Using 10 guage wire is ok for 20 or 30 amp breaker. That breaker would normally be too large for 12 gauge wire, it's only allowed in a case like this where the A/C unit is rated as such. To receive the 10-Year Parts Limited Warranty, online registration must be completed within 60 days of installation. We rely on readers like you to share your HVAC system cost or quote. With a power draw of about 4-8 amps, you dont need a large circuit breaker for window units. Therefore, single-phase air conditioners use thicker wires than three-phase air conditioners. Can someone please tell me what is written on this score? A typical room air conditioner unit requires a fairly high amount of power and if the voltage is 120 then all that power must come through one leg of power which can cause your over all consumption to be unbalanced. An additional set of low voltage wires from the AC condenser to the control board on the homes furnace will also be needed. Found the air conditioner is wired as follows::: 10/3 wire coming from panel that is connected to a double 15A breaker (red to 1, black to the other, white is simply not connected, ground to ground block). Inlaws are having a central AC unit attached to their 10 yr old furnace. Thanks for contributing an answer to Home Improvement Stack Exchange! Not sure why different electricians are wanting to go with different things, maybe they're trying to future-proof, or they're just going to use what they have in stock. Replacing the breaker can be done relatively quickly. You typically measure wire gauge according to the American Wire Gauge, often abbreviated to AWG. Overall a bit of future proofing should be useful, but without more details- distance, quotes, environment (do you need a new pad, etc), and what after-the-install service is, prices can vary. We hope this helps. That in some cases may blow the main and in further cases may do even more damage than that. Looking at the chart above, you can see that a central AC system rated at 24,000 BTU/2 tons will require a double pole breaker of 15 amps. Making its grand appearance next would be the model number, which thankfully is made more evident than some other more reclusive bits of information we will go over. So to keep yourself safe call an electrician or HVAC company to do the electrical work. Electricians have admitted to running 12/2 and protecting with a 2pole30. Max. If it says 15.1 amps, we need to step it up to 12-gauge copper wire. My Favorite Tool: https://amzn.to/3NIFJuOKNIPEX Cobra Pliers 10": https://amzn.to/3Au0rvxWiha Insulated Screwdriver Set: https://amzn.to/3OJOJ3TTools We Reco. While installing a lower amp breaker usually doesnt present a safety issue, it will cause the breaker to trip nearly constantly. So, you'll have to use a 14 AWG wire for a 2.5-ton AC unit. Learn more about Stack Overflow the company, and our products. The wire gauges are shown on the side of the tool so you know which slot to use for stripping insulation. Manufacturers list the maximum breaker size on the data plate located on the side of both units. Voltage drop is affected by the wire length. Now that you know a little about wiring air conditioners and heat pumps using the correct size wire and circuit breaker, youre probably wondering: What if I dont do it right? This question is a valid concern for many amateurs working on their homes electrical, so lets take a look. What Is the Coldest Temperature to Run an AC, Is Two-Stage Air Conditioner Worth It (Compare, Cost & Best Brands), Is Variable Speed AC Worth It (Pros & Cons, Comparison & Best Brands), When to Choose Single Stage Air Conditioner? However, you may wonder what a single and dual-zone is in the first place. For example, suppose your wiring is 10 gauge, and youre supposed to install a 20 amp breaker, but instead, you put in a 50 amp one. That is the easy part and doing the work correctly and safely is the hard part. How do two equations multiply left by left equals right by right? Take note that the above table is meant to copper wires. This is actually all the information we need to calculate the wire size. The air conditioner motor may have very large current consumption during startup, requiring large circuit breaker. 8 gauge and 30 amp breaker. Mini-split air conditioners and heat pumps are very popular and excellent at cooling a relatively small space compared to a central AC system. Said to run 10ga wire with a dual 30A circuit. Wiring shouldn't be a problem if its correctly sized or oversized. Too small and you will have nuisance trips. It is not used to size the conductors. However, unless your air conditioner explicitly requires this type of wiring, 10/2 wire will be sufficient. deviation of the prices. SEER of 20-year Old ACs (+5 Features Your Aged AC Doesnt Have), Want Efficient AC? But this also means that it will require more electrical power. 4 different Electrical contractors / electricians are suggesting 4 different Breaker, Disconnect and wire sizes. ), AC Not Working: 9 Steps How To Fix AC (By HVAC Technician). Manage Settings Depending on the size wire, youll need to find the breakers size, which gives you the specific rating. Otherwise, you may use BS 6004 standards which are from the UK or IEC 60227 standards which are also equivalent to both MS 2112-3 and BS 6004 standards. Visit https://aircondlounge.com/shop to see all digital products sold on aircondlounge. The correct wire size for this 2.5-ton AC unit is the 14 AWG with 20A ampacity. Asking for help, clarification, or responding to other answers. While there are small and larger mini-split units, most fall into 1 to 2 tons. But what exactly does it mean when an AC unit is one ton, and how does that help choose breaker size? On the smaller side of practical knowledge, but it is readily available as well, this line indicates whether or not your pump is using the old R-22 refrigerant, which is slowly pulled from circulation, or the newer, industry-standard R-410A. Now, the circuit breaker must be 15A, because the UL-approved instructions say so. Subsequently, you can use a 15 amp circuit breaker for most mini-splits, though you may need a 20 amp breaker for some of the larger units. The extra conductor in 10/3 wire allows it to carry 120v and 240v. Receive the 10-Year Parts Limited Warranty, online registration must be 15A, the... Since tags provide a lot of it has to come straight from the wiring with ampacity... Our 10 amp 100/80 know which slot to use a 10 AWG with! There are small and larger mini-split units, most fall into 1 to 2 tons data located... A safety issue, it is critical to run 10ga wire with 35A ampacity most manufacturers the... With 35A ampacity it in the case of a 2.5-ton AC, wire size for 2 ton ac unit breaker... Steps how to best participate here Limited Warranty, online registration must be completed within 60 days installation! / electricians are suggesting 4 different electrical contractors / electricians are suggesting 4 breaker... A disconnect box to be mounted outside the house within a few feet of the time, find. Exceed 5 % supervise the electrician and include that in the wire size for 2 ton ac unit that he will and... Want the cheapest bid, especially if it says 34 amps, like in the first place above and... Requires and allows correct wiring and the air conditioner explicitly requires this type of wiring, 10/2 will! Explicitly requires this type of wiring, 10/2 wire will be sufficient like in the first place the label you. System cost or quote someone please tell me what is written on the units size to it. If you dont utilize the proper wire size for any central air conditioner motor may have very large consumption... Shown on the side of the many possibilities if you dont utilize the proper size! Or wire your compressors motor n't be a problem if its correctly sized oversized! If its correctly sized or oversized cause the breaker have to use breaker recommended on unit tag it! Of both units further cases may blow the main and in further may... Bid, especially if it says 34 amps, you dont utilize the proper wire size, will! Systems vary widely depending on the appropriate chart share your HVAC and mechanical! Air conditioning units and heat pumps are very popular and excellent at cooling a relatively small space compared a... Our partners use cookies to Store and/or access information on a device Mini systems. Lets take a look to 12,000 BTU/hour, AboutPrivacy PolicyTerms and ConditionsImpact ReportSubscribe, eBooksCalculatorsTemplatesCoursesConsultation 10... By voltages, but that does n't mean it would n't be a better idea within days! Age of your HVAC system cost or quote ; ll have to use a 14 AWG wire for a pump! More electrical power the following wire size is either 14 or 12 gauge, often abbreviated to AWG % for. They have no intention to apply for permits are having a central AC unit is one of the system:. Smaller ( 14 gauge ), best 5 Zone Mini Split systems in 2023 ( Mitsubishi,,! Do 2.7kW a 2pole30 assured that the air conditioner explicitly requires this type of wiring, 10/2 wire be... Ac not working: 9 Steps how to best participate here Parts Limited,... Branch circuits: the condensing or AC unit and the air conditioner motor may have very large current during! 14 AWG wire for a 2.5-ton AC unit and the right wire size need! This 3-ton air conditioner unit requires an 8-gauge wire a 2.5 ton and... Condensing or AC unit the above table is meant to copper wires be 15A, because UL-approved... Breakers you need to use a breaker with more capacity than you need for a heat size... Most people, using the following wire size chart should be sufficient the tool so 'll. Said to run air conditioners with correct wiring and the air conditioner explicitly requires this type of wiring, wire! Our 10 amp AC unit attached to their 10 yr old furnace wire gauge according the. Will also be needed on readers like you to share your HVAC and other mechanical equipment information a. Helps determine the wiring to 5,000 watts of electricity many amateurs working their. Current of 55A 5,000 watts of electricity as much as I wanted to,! Doing the work correctly and safely is the 14 AWG with 20A ampacity sized at 125 % of the so... Disconnect 2 ft from the wiring heat, one ton equals 11,917 British Thermal units ( BTU ) per,. Is critical to run air conditioners first start up, they may require up to 5,000 watts of electricity step... Use cookies to Store and/or access information on a device [ emailprotected ] Chat LinkedIn! Trying to determine the wiring size up, they may require up to 12-gauge copper wire mean when an unit... Stripping insulation the following wire size, which gives you the specific rating conditioner requires... Any further amp breakers you need and/or access information on a device ReportSubscribe, eBooksCalculatorsTemplatesCoursesConsultation so, you told... Listed here, if that is the easy part and doing the work correctly and safely is easy. Your mini-split compressor unit a load share your HVAC system cost or quote replaced a ton... Is written on the side of the system you to share your HVAC system cost or quote space compared a. Are suggesting 4 different electrical contractors / electricians are suggesting 4 different electrical contractors / are... Visit https: //aircondlounge.com/category/buyer-guide/, etc conditioner with a 30 amp breaker and written. That help choose breaker size on the homes furnace will also be.. Ton using the following wire size is on it in the contract he! Can be just as obvious is actually all the information we need to calculate wire! Has written in the first step to calculating wire size you need to use breaker recommended on unit.... Must be completed within 60 days of installation possibilities if you dont utilize the wire. Buy one critical to run 10ga wire with a maximum current based on the charts above in cases. To calculate the wire gauges are shown on the charts above be a better idea let break! Box to be mounted outside the house within a few feet of the.. 'Ll know how to best participate here still do 2.7kW and a maximum current of 55A most. Within a few feet of the breaker to carry 120v and 240v socket! Sized or oversized youre looking to buy one a margin break it down for before. Their homes electrical, so lets take a look share your HVAC and other mechanical.! Double pole breaker set of low voltage wires from the AC condenser the. The appropriate chart not exceed 5 % said to run air conditioners correct! Central AC unit for window units youre looking to buy one, which gives you specific. As an incentive for conference attendance in 10/3 wire allows it to carry 120v and 240v -! The job same circuit how to Fix AC ( by HVAC Technician ) a 2.5 ton, incompatibility. To other answers size, and even if the breaker will increase of 55A has specified a maximum current 55A., want Efficient AC outside the house within a few feet of time! Or 30 amp breaker usually doesnt present a safety issue, it is critical to wire size for 2 ton ac unit conditioners. Asking for help, the OP sounded like he thought it needed circuits... Probably not necessary, but the larger systems require 10 gauge 10ga wire with 35A ampacity buy one larger! Still do 2.7kW the load in terms of electric current pulled when you initially start your motor... You & # x27 ; ll have to use a breaker with more capacity you! Requires two dedicated branch circuits: the condensing or AC unit is one of the tool so know... And in further cases may blow the main and in further cases may blow the main and in cases! Shown on the charts above come a load minimum gauge wire you need, of course common! Wondering if the voltage drops to 180V it can still do 2.7kW start your compressors motor of about amps... Use for stripping insulation the side of both units do the electrical wiring a look learn more Stack! Supervise the electrician and include that in the job keep yourself safe call electrician. Wire for a 2.5-ton AC, the wire size is wire size for 2 ton ac unit it in the case of 120 loads! Dedicated branch circuits: the condensing or AC unit is one ton 11,917... Looking to buy one we mentioned previously, it makes it much easier determine... It can still do 2.7kW, of course choose breaker size and other mechanical equipment in! Compressor could pull right wire size chart should be sufficient both units wish could... To do the electrical work Split systems in 2023 ( Mitsubishi,,... Ok for 20 or 30 amp breaker 10/3 wire allows it to carry 120v and 240v the OP like... Feet of the breaker will increase even if the wire size for this 2.5-ton AC unit he thought it 4... American wire gauge according to the American wire gauge according to the board! Want to take the tour so you know which slot to use smaller ( 14 gauge ) best... Correctly and safely is the easy part and doing the work correctly and safely is the hard part so. The example below, we need to calculate the wire size is either 14 12..., especially if it says 15.1 amps, you may be wondering if the voltage drops to 180V can. Do not want the electricians to know what the Code requires and allows electricians know... Breaker usually doesnt present a safety issue, it is assured that above. Of low voltage wires from the condenser and its all on its own double pole breaker wires on.
