Can anyone help?!! Back last winter I noticed that we could not get heat to come on at times and this summer the air conditioning seems to be changing to heat at times by itself and then back to AC. I have checked freon level and pressures, compressor clutch operation, fan clutch for proper operation and all have seemed to be correct. I think it is going to heat because the air temp changes to very cold to very hot and then back to cold again. Is there a control module or blend air door module that could be creating this problem? We have noticed that it has gotten progressively worse during this summer or should I say more frequent!

 

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