Heating, Air Conditioning, Fridge, HVAC/A/C power cable


Hi Joe,

I have a small electricity tester that looks like a pen or a marker. When it gets near or intouch with a "live" wire, an indicator light turns on in the tester. My A/C blower unit has a thick power wire, with 2 thinner wires that run along the thicker wire, spiraling around it. If I touch the thicker wire with this tester, it lights up. Does that mean that the wire isn't shielded properly, and some of the electricity is "leaking" out? or is that normal?

Thank you in advance

Best regards,



The two small wires may be your low voltage control wires ( 24 volt ac ) don't believe your voltage tester picks up 24 volt. When you touch the tester to the line voltage ( thick wire ) your not leaking out, just tells you that wire is live ,has power nothing more. All is normal.

Heating, Air Conditioning, Fridge, HVAC

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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