Depending on the temperature of the yeast, you could have shocked it when you pitched it into the very warm wort. Typically you want as small a temperature difference as possible with liquid yeast.
I'd advise improving your wort cooling abilities. IMO 79F is HOT. If you can't get it cooler than that before going to fermenter, then set up a swamp cooler to get it to where the yeast needs it to be. With my batch last weekend I wasn't able to get the wort as cool as I wanted it to be (was in the upper 60's). I used a swamp cooler to get it to the low 60's within a couple of hours and then pitched my slurry. The yeast thanked me by going to town on the batch and finishing pretty quickly (within a few days it had dropped to ambient temp, after increasing to the mid 60's).
I also wouldn't really start to worry (much more) about things until it's been more than 72 hours without ANY sign that the yeast is doing anything. Depending on what you ferment in, that could be off-gassing (airlock movements) or an increase in the wort temperature (which is my main indicator). I ferment in converted sanke kegs, so looking at the brew while it's fermenting isn't an option. As long as my fittings are tight, the excess CO2 can ONLY go out via the airlock. I also have a thermowell going to the middle of the fermenter, which I put a temperature sensor down. That's what I use to get temperature readings of the fermenting (or finished) beer. The thermometer unit I use keep track of the high, low, and current temps from the sensor. With a reset between batches, I KNOW when it's actually done. I can even go away, or not look at it, for an extended time and then see it peaked and has dropped back down. Thus indicating fermentation happened and has finished.