Heating, Air Conditioning, Fridge, HVAC/Carrier Tech2000ss


Hi Craig,

Last night we heard a pop noise outside.  This morning I noticed the air coming through the vents was not as cool.  So I turned the temperature down more and then the air was cooler.  I went outside to check the AC unit, Carrier Tech 2000SS, and there was a hissing sound coming from it but it was still running, the fan was moving, etc.   I came inside and turned off everything and now I'm hoping you can give me some advice. Money is tight and I can't afford to get an expert.

Thank you in advance for your help,


To start with, turning the t-stat cooler does not make the unit blow any colder.  It might turn the unit on and it will also make the air temp inside the home colder.  The hissing sound could be a few different things. Units make noise when they run.  Without me hearing the noise and giving the unit a once through, I cant even begin to determine what, if anything, is wrong with your unit.


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Craig HVAC Expert


I have been in the HVAC field for the past 18 years. I can help with most HVAC questions. I work on commerical buildings for the most part, and have yet to find anything I could not troubleshoot and repair, when repairable. I work on small 1 ton units to a 2500 ton chiller. Troubleshoot air flow, elect, and control problems. I attend regular classes to keep up with the latest and greatest.


I work on commerical sites, hospitals, gov't buildings. I can troubleshoot just about anything in the HVAC business.

5 years trade school, VFD training classes, Liebert factory training, some York and Trane factory training.

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