When to add Whirlfloc?

The title says it all. I've seen where folks add Irish moss at 15min; is this the norm for Whirlfloc as well? I tossed a tablet of Whirlfloc in at the beginning of the boil (60min) tonight, any issues with this? This is my first time using it.
Also first partial mash attempt. Looks like my efficiency was a bit low (OG 1.050 vs. 1.059 calculated at 75%).
It took me forever to cool my wort (nearly 1.5 hours to 80F) so I'm a bit worried that i won't get a good cold break. I ran out of ice after 45 minutes in the sink. Next time I'll buy an extra bag.
Also managed to melt my auto-siphon. Oh well. All in all, not the best brew session. And I didn't start drinking until halfway through the boil.

Thanks
Terje

Yep, add it the last 15 minutes and all will be good. I like it better than Irish Moss.

I just picked up a pack from AHB and will be trying it Sunday on BM's SWMBO slayer - belgian blonde. Gonna show a fellow extract brewer how AG is done.

I've always added it at 15 min left in the boil... sounds like its time for you to get a chilller, it'll only take you 10 minutes to get it down to 70F, best $65 I ever spent.