Heating, Air Conditioning, Fridge, HVAC/Trane Weathertron Thermostat


Hello Joe,
I think you are the one that helped me with my questions about the heat pump.  Great news, it works.  The only problem is that the two merc. levels do no appear to be synchronized.  The Fan and the heat do not turn on and off together at all.  The fan runs and runs and runs.  Do you have any ideas?  
Thank you,


If you have the fan in the ON position at the t-stat the blower fan runs 24/7 independent of the Heat or A/C. You have a two stage t-stat , the top bulb on the stat energizes the Heat pump, ( during heat position ) if the outdoor temperature gets to low whereas the HP can not handle the load the bottom bulb makes and brings on your electric heat ( usually a 2 degree differential ) In cool mode, the top bulb energizes the Reversing valve outside ,and the bottom bulb energizes the outdoor unit and indoor fan ( fan in auto position ) If you have the fan in " auto " and the system off and the blower fan still runs ,either your fan relay is being powered when it should not be.If your fan does not run ( after t-stat satisfied ) in cool mode but stays on in heat you probably have a wiring issue. Never units have a time delay fan relay where as the blower fan starts a few seconds after it calls for heat/cool and runs upwards off a minute after set point is reached and the outdoor unit shuts off. If you live in a cold climate ,while in heat mode the outdoor unit and fan will run for a very long time before it cycles off. Your refrigerant charge may not be off slightly, ( works OK for cool ) your return duct may not be sealed and  be letting cold ambient air into the return and lowering your supply air temperature.You may not have the filter panel on and cold air is being pulled into the return duct by the filter. Suggest calling for a PM ( Preventive Maint. ) check if your unit has not had service in a couple years.

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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