Emile Heskey and Ryan Griffiths scored in each half at Hunter Stadium as the Jets climbed back into the top six with their first win in five games.
The result in front of 11,396 fans continued the Heart's disastrous run away from home, their sixth straight loss on the road leaving them sitting perilously in sixth spot.
Jets coach Gary van Egmond made five changes to his starting side, including three in defence and a first start of the season for English striker Michael Bridges.
And it had the desired effect, with Bridges impressing in a classy display and striker Adam Taggart also making an impact after being promoted.
Griffiths and midfielder Zenon Caravella were other strong contributors while Heskey was a tower of strength up front.
He gave the home side the lead after just nine minutes, taking a first-time shot well after Griffiths unlocked the Heart defence with a clever through ball.
The visitors had several chances to hit back, with dangerous striker Eli Babalj causing most headaches in attack.
He wasted one chance in the 13th minute but was unlucky not to equalise when his volley struck the post from a Richard Garcia cross.
Taggart and Heskey also had decent chances late in the half and the home side looked in control as they headed to halftime in front.
The Heart started the second half strongly and came within centimetres of an equaliser through Nick Kalmar in the 53rd minute.
Brazilian playmaker Fred made his return from a quad injury off the bench but the Heart hit a flat spot with little created in attack.
Taggart was unlucky not to extend the Jets' lead in the 65th minute, striking the left post with a low shot from just outside the box.
But he capped a strong performance when he set up the Jets' second in the 81st minute.
Taggart found Griffiths with a looped through ball and the striker controlled beautifully before craftily scooping the ball over Heart goalkeeper Andrew Redmayne.
Van Egmond admitted it was a tough call to drop the likes of young guns Craig Goodwin and James Virgili to the bench but felt the inclusion of new faces worked a treat.
"It was time (to make changes)," van Egmond told Fox Sports.
"As you saw tonight, we always looked dangerous going forward. It always looked like we had goals in us.
"I thought Bridgey early on, when he was nice and fresh, did some very clever things ... hopefully he can derive a lot of fitness out of this and continue."
Heskey said the performance augured well for the Jets' remaining six regular-season games.
"We knew how important the game was. It was one of those ones we knew we had to win," Heskey said.
"When we perform like this, that's what we're capable of doing."
Heart coach John Aloisi was disappointed his men didn't take their chances in the first half and admitted the winless away form this season was a serious problem.
"It's not good - we know that," Aloisi said.
"We're trying to put it right but now we've got a home game to look forward to next week (against Sydney FC). It's a big game for us.
"We're still in finals contention and we have to keep working hard."
New Dutch recruit Marcel Meeuwis made his debut off the bench in the 62nd minute and Aloisi said he would be better for the run.