Heating, Air Conditioning, Fridge, HVAC/HVAC Thermostat


When the house was built ('85) we had a digital thermostat, the blew out during the first close lightning strike.  Same thing happened with it's also-digital replacement, and we saw sparks fly from the thermostat at the time of the strike. We did not loose power either time.  We then installed a mercury switch thermostat and have had no problems since.

I'd like to switch to a programmable thermostat, but I don't want to loose it in the next storm.  We have installed a whole-house surge protector not too long ago.

So can I now safely install a new digital programmable thermostat?  What else could it be?


Usually digital t-stat have built in manual resettable overloads, your old one may have had one , also try removing the battery, or run without batteries for a while, chances are you would need the C or common wire hooked up from the transformer going to the stat. Possible your Air Handler and Or outdoor unit is not properly grounded. Other than that , I do not know what else to tell you.  

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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