Harvey carried his bat for 71 off just 56 deliveries - his second half-century of the tournament - guiding the Renegades to a total of 6-140 after being sent in to bat by the Brisbane Heat at Metricon Stadium.
But the Heat were up to the task with the bat, chasing down the score with five wickets and three overs to spare.
Harvey and Harper again put together a strong opening partnership, combining for 38 runs.
New skipper Nic Maddinson - on his Renegades debut - came in at three and scored 19 to help lay the foundation.
Harvey was brilliant through the middle overs, finding the gaps and scoring eight boundaries.
A late six from all-rounder Will Sutherland helped set the Heat a chase of seven runs per over.
The Heat got off to a fast start through their superstar, Chris Lynn (32 off 15).
But when spinner Zahir Khan rattled his stumps, the Renegades worked their way into the game.
Zahir picked up a second wicket, and fellow spinner Mohammad Nabi chipped in with one of his own to see the Heat slip to 3-67.
Jack Prestwidge and Kane Richardson also picked up a wicket each, to pull the Heat back to 5-107 in the 14th over.
From there, the Heat rode their luck and finished with some big hitting to wrap up the game in the 17th over.
Zahir finished with figures of 2-27, taking his season tally to seven wickets and collecting the BKT Golden Arm cap in the process.
The Renegades now have a break before returning home to host the Perth Scorchers at Marvel Stadium on December 22.