On older Adler Barbour units there is a white plastic Terminal Block where all the external wiring enters the unit. These are screw down terminals and somtimes a wire comes loose. There is also at least one fuse assembly to check there as well to see if a fuse blew. If you see any eveidence of blackening/melting at the terminals...wait for a pro...but you may save a few bucks if you check these simple things first. Good luck!
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