Phillips, 39, has now scored five goals in seven appearances since his loan move from Blackpool and his treble killed off the challenge of their promotion rivals, who drop to third.
Hull manager Steve Bruce was incensed by the penalty decision that allowed Phillips to put the hosts ahead on the stroke of half-time, but there was no controversy about his second-half brace that put Palace firmly in control.
"The bloke is so professional and is still as fit as a flea. He's got the lungs of a 26-year-old," Holloway said of Phillips.
"I'm just delighted he understands how I want to use him here.
"I knew that with the wide players we have here he would be the ideal man to get on the end of things.
"Now it's all about keeping the energy of the squad and bringing things together.
"We have beaten a very, very good team and we know it will be tough between now and the end of the season.
"You just have to keep trying to win every game because if you lose a game at this stage, it is hard to get over the disappointment."