Did the same thing in Havasu once. 2:00am mind you. The damned things are all wired together. If one battery goes dead, they all start to chirp. Vaulted ceilings, too many road sodas , and a 6 foot ladder only compounded the matter.
So I did what any other red blooded American would do........I got the ladder, climbed all the way to the top step , reached as far as possible, got a hold of the alarm, damned near fell on to the sofa , took it down, put it in the dryer full of towels. I was not going to spend one more second on that 'n worthless POS!!!!