	AllExperts > Electrical Wiring in the Home
	Search

About Master 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.

You are here: Experts > Home/Garden > Home Improvement/Repair > Electrical Wiring in the Home > central air fan and compressor wire

Electrical Wiring in the Home - central air fan and compressor wire

Expert: Master Bob - 8/24/2004

Question
i installed new main panal house 120\240. Trying bring 240 volts out to the compressor and fan for ac unit.Put in a two pull breaker a and b fase wired them together at the outside disconect to make 240 blowing the breaker.How do i get 240 out of my Panal?

Answer
Hi Phillip,

Sorry for the delay.....we are recovering from a computer cooling fan malfunction a few days ago....online time has been limited while we've been restoring data and files...

You didn't state the electrical specs for your central air unit....and they range in size from a 20 amp circuit to a 50 amp circuit (and up). The minimum circuit ampacity and breaker size will be stated on the unit's electrical nameplate.

A 20 amp unit will need #12 copper.
A 30 amp unit will need #10 copper.
A 40 amp unit will need #8 copper.

If the breaker is tripping - one of three things have occurred:
1). the 2 pole breaker (and wire) is sized too small.
2). the compressor motor on the central air unit is seized up and will need to repaired or exchanged.
3). there is a direct short in the wiring - either to the unit...or inside the unit.

Please follow-up with the electrical nameplate data for your unit....and the breaker (and wire) size used at the main panel....and the disconnect size outside by the unit. This will help me to determine what may need to be done to correct this.

Best Wishes,

Bob Osgood
Master Electrician

RKO ELECTRIC

www.rkoelectric.com

Ask a Question

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