installed the heat & air in my new home, repeatedly told them that there was something wrong since the upstairs was blazing hot and downstairs not so much, owner finally came out and said that there was nothing wrong with it, it was me. Turns out that not only was I correct in the fact that you wired the downstairs unit to the upstairs unit but it overloaded and stopped working. nothing like telling them what to look for cause the expert could not figure it out!
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