That's crazy and ridiculous. Do you have any kind of WOH status? If so, I would try calling WOH corporate and ask them to get involved.

Here's how I see it:
1. They put you into a room that should be out of service (non-habitable). This should be in violation of some kind of Hyatt corporate policy.
2. They should have "walked" you as the poster above describes (booked you into an comparable alternate hotel, paid for the hotel, and provided you with a full refund).
3. You should not be paying for ANY nights in that room with no A/C.

My suggestions:
1. First, ask to talk to the Hotel GM. Raise the points above (nicely) and state that it is well below Hyatt standards for them to treat you in this way.
2. Make clear that you will be posting a zero star review on TripAdvisor, as well as possibly Facebook, Yelp, and Google. This is to warn future travelers that this hotel forces guests to stay in non-habitable rooms.
3. Make clear you will be reaching out to Hyatt Corporate and will file a report with them ([email protected]).
4. Ask him/her to resolve this matter to your satisfaction.
5. Take names (ask for business cards) from everyone you talk to.
6. Contact World of Hyatt (or the travel agent that made your reservation).

It really sucks that they are putting you through this. It's unfair, and wrong. You deserve compensation. The Hyatt Regency Kaanapali is also a GREAT property. Try to get them to move you there AND cover your room cost!