I recently purchased a ductless mini split and am trying figure out the correct breaker and wire size. 8 Answers. Here are some common reasons you can take into consideration. These rating are adequate for runs of up to appx 60 ft Bummer. The wire run one way will be 15ft. The protective device must protect against short circuit, overload, and earth fault conditions. Kevin, the issue is not what size circuit breaker you should install, the issue is to make sure that the installed circuit will be exactly what the air conditioning unit is specifying which in this case is a 30 amp 230 volt circuit. David, discusses replacing a breaker, wire size #6 copper: 10kw heat strip, 60 amp breaker. Water heater wire size. The final cable size will depend on the derating factors applied for the installation. Well, an air conditioner usually trips the breaker because it's pulling in more amps than the breaker is rated for.That is, if you have a 20-amp breaker and the AC pulls 30 amps, the breaker trips. Included in this cable will be a #12 bare ground wire. This is the way I figure it when the nameplate rating is unknown... 1-ton equals 12,000 BTU's = 10 amps. posted 2016-Jul-4, 11:43 pm AEST ref: whrl.pl/ReE1JR. It depends how far over the rating is, but the basic idea is the breaker (and the wiring it protects) can handle the inrush current from the air conditioner compressor coming on. The device is therefore NOT sized to protect the wire against overloads. Subscribe for weekly inspiration. last updated – posted 2016-Jul-11, 4:21 pm AEST posted 2016-Jul-11, 4:21 pm AEST User #318206 460 posts. A low-rating circuit breaker (MCB) is used. Typically, 2.5mm2 cable is used for 16-20A circuits, while 4mm2 cable is used for 20-25A circuits. Actual current rating of circuit will depend on the method of installation,eg, unenclosed in air, or enclosed in conduit over 50% of its route length. In the example below, it’s 60 amps. As for the disconnect. Relevance. Disconnect Size. Water heater circuit breaker size. The air conditioner must be on a dedicated circuit breaker not shared with other outlets. It is not uncommon to see a 50 Amp breaker on a The breaker and wire size will largely depends on the power consumption (W) of the air-conditioner. Use 10 awg for 30 amp unit or 6 awg for 60 amp unit. Here’s a picture of an air conditioner’s data tag that I took just today. 2.5kW air-conditioner will draw somewhere around 0.6 - 0.7 kW of electricity. Your AC circuit breaker will trip if it is pulling in more amps than your circuit breaker is rated for. To determine the right circuit breaker size for an air conditioner, we look at both the minimum and maximum size allowable. Circuit Breaker Size To determine the right circuit breaker size for an air conditioner, we look at both the minimum and maximum size allowable. A 4 and 5 ton air-conditioner will likely need a circuit breaker rated 45-50 A connected with 8-10 AWG wire when supplied with 197 – 253 volts.. Circuit breaker for air conditioner. In your case, the circuit breaker should be a 20 ampere HACR breaker. Air blast circuit breaker is small in size, because of the growth of dielectric strength is so rapid (which final contact gap needed for arc extinction is very small). We are installing a 240 volt, 18000 btu air conditioner. the air conditioning units work for 2 months then all of a sudden a issue arises where the supply blows. By the time the breaker is in danger of tripping the current draw has dropped down below 15 amps. Table 310-16 shows that three wires of 6-gauge placed in a conduit will safely conduct 65 amperes of power. Arc quenching is much faster; The duration of the arc is same for all values of current. 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. So yes, it can be simply plugged in if you wish. The obvious first thought is that the inverter air conditioning unit itself has a major problem such as a PCB or compressor fault. 1. [Solution] If Circuit Breaker (MCB Trip) activates during operations, please check the followings. Overload protection is built into the compressor itself. (You can see that, right?) The biggest problem with an underrated RCD breaker is that it can be a periodic issue, i.e. Size of Wire & Circuit Breaker for Electric Stove 3 How Many Watts Does a 5,000-BTU Air Conditioner Use? If the air conditioner is not on a dedicated circuit breaker, the unit may power on but not run. Types of Air Conditioners and Their Electricity Requirements Mini Split Air Conditioner Electricity Requirements. Reset it once and only once, and see if your unit runs normally. Philchat. Most likely you need 8-3 with ground thnn or thwn with 50 amp disconnect mounted within several feet from unit with a 50 amp circuit breaker in the main distribution panel. Air compressor circuit breaker size? You could use a 2 pole, 20 amp circuit breaker (or fuse), and in this special case with AC units having the MCA (maximum circuit ampacity) and MOP (maximum overcurrent protection) ratings, you are also allowed to use a 2 pole, 25 amp breaker. Step 2. The manual for the IR air compressor calls for 3x the FLAs. what size circuit breaker for 18000 btu air conditioner? The 30 amp circuit requires #10 AWG wire or 10/2 cable that will be protected by a 30 amp circuit breaker. Forum Regular reference: whrl.pl/ReE1JR. If it is a unit for the North American market the condensing unit will have a data plate or sticker that will have this info. Always be careful with resetting a circuit breaker. Am I compliant using #10 nm-b from the panel to the unit and having a 45 amp breaker or am I still required to have a 30 amp breaker? Using the wire amp rating to gauge calculator, the recommended wire gauge is 10 AWG. The size of the circuit breaker is determined by the manufacturer, and should be listed on the nameplate. Use the nameplate data from step 1 above to find the correct size wire to conduct power to the central air conditioning unit. 6 Why Does My GFI Breaker Keep Tripping? It is an old GE window model. What size wire and circuit breaker do we need? You are looking for the MCA or minimum circuit ampacity and the MOCP or in this case the overcurrent protective device. Circuit Breaker Size. Air Conditioner Circuit Breaker Keeps Tripping – Reset Your Air Conditioner’s Circuit Breaker (ONCE, and ONLY once!). Favourite answer. Answer Save. The vast majority of mini splits require 208/240 volts. 7 years ago. This means it is allowable to install this unit on a circuit breaker rated at 50 amps and a conductor rated at 28.6 amps, according to the NEC’s NFPA 70. Cable size should be as per the Australian Standards (AS 3000 and AS 3008). I always thought you choose the wire size by the mca of the unit and then use the max breaker size. The electrical characteristics for my LG ductless mini split are as follows: MOP 35 amps MCA 23 amps Cooling rated amps 17.55 Heating rated amps 17.55 Compressor 17.3 amps Fan 0.25 amps However, if your air conditioner keeps tripping the circuit breaker, then it might be a cause for concern. Check whether Switch is ON and the Power is supplied. This is the heater’s minimum current rating. I only have a 20 Amp circuit breaker and it works well with the cooling of the air conditioner. It then says that the max breaker is 45 amps. The 40 amp breaker would only be slightly less than 3x rule. A 5 ton air conditioner will need a two pole 40 amp circuit breaker to supply 240 volts over a cable of #8 copper wires. A 5,500 W heater rated 240V has a rated current of 5500/240 = 22.91 amps. The voltage range for this wire falls between 0 volts and 2,000 volts. This is good for 50 amp rated unit. All mini splits require a dedicated circuit. If possible, ask your spark to run a new circuit from your switchboard. The maximum size will be clearly labeled on the compressor label. The Circuit Breaker Size for a 230 Volt Air Conditioner Kevin, according to the specs for the air conditioner the circuit that should be installed would be a 30 amp 230 volt circuit … Notice that the MCA is 28.6 amps and the maximum fuse or circuit breaker is 50 amps. Archive View Return to standard view. This is a 2-ton air conditioner, as you can see from the model number. Take a look at the Lennox air conditioning condensing unit tag on Page 19. However when using the heater the demand for more electric power trips the circuit breaker and shuts off. 3. The wire to a condensing unit must be large enough to allow the equipment to start. Step 1. That said, for aesthetic reasons I'd hard wire it certainly. Breaker size should be what is recommended in the AC manual. 4 How Does 2-Pole Circuit Breaker Work? For air conditioners and heat pumps, we size the wires and circuit breakers in accordance with the information printed on the label, not the simplified sizing charts that we typically rely on. posted 2016-Jul-4, 11:43 pm AEST O.P. Let's say I have an air conditioner with a minimum circuit ampacity of 28.2 amps. The reason for this is that the unit does not require as much power to display the settings, or even run the fan, as it does to turn on and run the compressor. 2. What’s unusual about this number on air conditioner data plates is that it often doesn’t jive with the chart I listed above. If it keeps tripping, then something is wrong! Check whether the 16 Amp good Quality Top plug is used or not. Some smaller capacity units only require 110/120 volts. What size circuit breakers and wire size do I need for the following air conditioner 5 tonn condesor unit with following data plate information... volts 208 - 230, volts range 197 - 253, max circuit breaker 50 amp. Hi all, Building a new home and the air con … Currently I have a 220v, 30 amp breaker with 10 AWG Romex. 2.5sqmm will carry 25A unenclosed.in air. CaptDan In electronics terms a circuit breaker is a relatively slow device. Well, trust me. So you've determined that your AC is tripping the breaker, but you're clueless as to why. The breaker or fuse ahead of the air conditioner only protects against short circuits and ground faults. mlionel20. If I decide to just use the air conditioner and not the heater, is a 20 Amp circuit breaker sufficient to power the air conditioner. While trying to justify a 40 amp circuit breaker for my 5hp, 3 phase, 240 V air compressor I came across a chart of unknown origin that called for 2x the FLAs of the motor, which is 13.9 according to the motor data plate. 5 Can a Refrigerator and Microwave Be on the Same Circuit? Depending on the BTU capacity amp requirements can range from 15 to 45 amps. Speed of circuit breaker is much higher during operation of the air blast. If there is a dedicated circuit that is 240 volt and the new air conditioner requires 110-120volts then the existing circuit may be converted from 220-240 to 110-120 volts if the amperage rating is the same for the existing circuit as the required power for the new ac unit. For instance, your 30-amp circuit breaker will trip if your AC is drawing in 40 amps. subject to … Looks dodgy to have a GPO on the wall next to the air-conditioner. COVID-19 Update: To see what we're doing to help keep everyone safe, please see COVID-19 and Home Inspections. 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