Bests & Worsts Reviews from Amazon

Basically we have a large home and bought this to keep our bedroom ice cold at night because my wife is having hot flashes. Will not cool a 260 sq ft bedroom below 72 with a central AC set at 78 helping out. Compressor never shuts off. I returned the first unit because B&D told me it was defective (some Indian reading from a paper) and Amazon sent another. The new one does not cool below 73 this time...with central AC st at 78. Again B&D told me the second unit is defective. I don't believe it. Cool air blows out the same amount in both units. I believe these are no way near 14000/8000 BTU's They have to be lying because if they were they should cool a 500 sq ft room without need for central AC helping and again my bedroom is 260 sq ft. ****FOLLOW UP***** I spoke to the Black and Decker supervisor and they admitted that no....the unit will not cool my room below 72...even though the Central AC is supplementing by being set at 78. They said the customer service help person was completely wrong when claiming the units were defective. They said that basically...even though they claim a 500ft room size....in reality they are designed for apartment sized bedrooms (about 120 sq ft) with 8 foot ceilings (I have a 10 ceiling).