I had a similar problem at the Courtyard in downtown Phoenix several months ago. I called after the stay and got 35,000 points, equivalent to the going rate for the hotel (I paid cash on corporate rate). I'm Titanium, if it matters.
In my situation, it was not just no hot water...no water at all. Just a bare trickle enough to brush my teeth and wash my face. I tried to call down to report it, but I also then learned that the phone in my room didn't work. As I was leaving for the day, I let the front desk know and got a "Yeah, it is the whole hotel. Sorry." No real concern for the fact that no one could shower...and no indication of when it would be corrected. It did get fixed that night, but there was never any communication/real apology from the hotel management about the situation. An email/note under the door would have gone a long way. I also mentioned it at check out and got no reaction. I finally called Marriott CS when I got home. The water thing happens, but the communication was the tipping point. As a contrast, the Westin Lake Mary/Orlando North was going to shut water down for a couple of hours overnight last week and notified all guests.