Room temperature juice

Yesterday, I inaugurated my new Omega VERT. It is an awesome juicer. My old juicer "juiceman" would hop all around the island when I would attempt to juice hard veggies and was pretty loud. It did help me to introduce me to juicing when I was not a serious juicer. Well, surely juiceman is/was not meant for serious juicing.

Omega VERT is relatively quiet.I did find that fiber is still an issue with veggies like celery and tough greens, especially celery. By the end of juicing my VERT was hot. Am I overworking it? Should I be giving time for it to cool down before resuming? 

I juiced 25 lbs of carrots, 3 bunches of beets, 4 bunches of celery, two bunches of dandlion and 2 bunches parsley and some garlic. I got 20 pints of pure unadulterated juice...Slurp!!!My son drank an entire pint without refusing ....isn't he an awesome boy??

My question: Can I keep the juice that I need for the day, out on the counter about 8 hours before? How do you all bring the juice to room temperature? 

Thanks for all your inputs in advance..

HJ