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Heating, Air Conditioning, Fridge, HVAC/a/c & intertherm air handler problem


i had a new goodman ac unit installed 3 weeks ago. the intertherm
heating unit heat strips keep coming on.  the tech has been back
5 times and everytime he leaves it is cooling properly but within
two to three days the heat strips come back on (naturally when i'm
not home) blowing 120  degree heat out.  i suggested it was a wiring issue. i know i need a new tech but i already have a lot
invested so i just need if fixed.  HELP


The inexperienced service tech. is probably overwhelmed due to you having a mismatched wiring diagram, Goodman to a Intertherm Air Handler. If this is a A/C only unit and not a heat pump, I would remove the W wire on the t-stat and at the air handler W terminal and run system without it. If your heat does not come on ,possible your t-stat is not correct for your application or the t-stat is miswired. If it still comes on you would need to look at the wiring diagram at the AH and the t-stat and trace each wire to the wiring diagram. Also possible it was miswired from the factory ( if new Intertherm unit ) Some t-stat have a switch on them to run either electric heat or oil/gas. To me it's a miswiring somewhere. Is the Intertherm indoor unit new also? Typically your suppose to get a one year labor warranty on new systems and all these call backs should be covered,providing the indoor and outdoor unit and heaters are new. Why can't you ask for a senior tech. from this company.

In closing you would have to check each wire feeding the electric heat relay(s) to the wiring diagram 24 volt control circuit. Verify the t-stat is correct for the application and wired correctly to the AH and the AH low voltage wiring is correct going to the outdoor unit.

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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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