Does the breaker stay on with the disconnect off? Is the unit 120 or 240 volt?
Correct!The blades of the disconnect are creating a dead short from hot to neutral. Remove the neutrals from the terminals and splice with a wire nut.
There's no way that is right. 12,000 BTU/hr is like 3000 watts and that equates to 29 A @ 120V.Senville, 12,000 BTU, 115VAC, 12 gauge wire, 20 amp breaker, disconnect box. tripped right away.
Did you change anything else? I know I initially said the neutrals were the problem, but changed what I said as the neutrals were only being disconnected, not shorted.We disconnected whites and marreted them together. Tada! I guess we had it wired in a 240 disconnect box instead of 120. Oops! Heat pump works! Yeah! Thanks guys for all your help. What a great resource Having this chat.