AboutMaster Bob Expertise Master Electrician / Owner RKO Electric (USA Only) - can answer most of the typical residential, commercial and industrial electrical questions regarding new installations, wiring additions, lighting, switches and receptacle outlets and electrical upgrades of any nature.I will make every effort to respond to your questions as soon as possible at the end of the work day...very busy electrical company - your patience is appreciated. Stop by and see us at: www.rkoelectric.com
Experience Licensed Master Electrician with over 32 years licensed experience - updated with the latest NEC Codes every 3 years. Over see the daily electrical operations of two electrical companies. Also serve as a judge (for Electrical Contracting Products Magazine) to help select which new products are fit and safe for electricians and the electrical market.
Im glad people like you are around for the do it yourselfers.
I am installing a ductless mini split air conditioner in my home its a 24,000 btu cooling unit. rated amps of the unit is 9.7 amps its also a 208-230 volt single phase. my question is running the sub panel from the main panel i would install a 30 amp dual pole breaker since its a 208-230 volt phase or a single 30 amp breaker? also the size wire from the breaker in the main panel to the sub would be a #10 copper wire? this sub panel should be no longer than 75 feet from the main panel as this would cause a fire? I would want to use this ac 30 amp sub panel? http://www.lowes.com/lowes/lkn?action=productDetail&productId=95550-82364-DP221R...
If you can help me thanks i will have a certified electrician check my work before i flip the breaker to power it up.
Answer Hi Jason,
Happy to be able to help out the D-I-Y's....just have such limited time to do so....own/operate a very busy electrical company.
Based on the information you supplied....this is NOT a sub-panel you are installing - rather a safety disconnect to shut off power to the A/C system for maintenance. Code requires this disconnect to be within site of the A/C unit...so if you are mounting it out on a pad outside the home...you'll need to mount this disconnect out on the exterior wall (approx. 4' above grade) and run liquid-tite down to the unit connection box.
This sounds like a small unit (like the Mitsubishi Mr. Slim or similiar...) - with a 9.7 amp rating. IF that is the actual rating (a metal plate or sign on the front or side of the unit will give the amperage rating and size of over-current fuses and breaker)....then you will NOT want to use a double pole 30 amp breaker at your main panel...more like a 15 amp double pole breaker (or what ever the unit actually specs on the nameplate).....and install the same size fuses outside at the disconnect.
However....you can still run #10 wire from your main panel's 15 amp double pole breaker to the outside disconnect and in the liquid-tite down to the power connection box on the A/C unit - given the distance you state - to help minimize voltage drop. (Note - you can always go with bigger wire then necessary - just never smaller)
NOTE: Most small disconnects are rated for 30 amps (this is the smallest size you can generally find) - but you do NOT want to use 30 amp breakers or fuses....go with a 15 amp dopuible pole breaker or whatever the spec of the unit states for breaker and fuse size...I'm SURE it's not 30.
Make sure the disconnect you install (the Lowe's link does not have much info - just a picture) is suitable for outside use...(NEMA 3R minimum)
I can send you a picture of what this all looks like outside if you'd like - please respond with an email address....and I'll send you one to it when I get the time...
Hope this helps Jason....if you need more information ...or have new questions...please follow-up
(** NOTE: I will be running electrical projects out of the area for the next several days - and will need to mark myself as away " on vacation" until I return. If you need more info - you can always reach me by direct email at:
info@rkoelectric.com
I will have very limited chances to check email while on the road...so please be patient for any response.
About Electrical Wiring in the Home
This site answers questions related to home electrical wiring, home wiring, general electrical help,and other electrical questions related to aleternating current (AC). You can find help on the National Electical Code, home electrical issues, wiring electrical outlets, installing lighting, electrical grounding, and general electrical help for do-it-yourself projects not require an electrician. If you do not see your home electrical wiring question answered in this area then please ask your electrical wiring question here
