Heading into the contest just a point adrift of safety, West Ham knew a victory would see them climb out of the relegation zone at the expense of rivals Tottenham.
Despite that incentive, it was Wolves who started on the front foot in East London, as André powered an early effort over the bar from range.
The Hammers grew into the match, and they spurned a glorious chance to take the lead when Crysencio Summerville fired wastefully over from eight yards after a superb dinked pass from Mateus Fernandes.
Both sides continued to threaten as the first half progressed, with Jarrod Bowen seeing a tame effort comfortably saved by José Sá, while at the other end, Adam Armstrong was unable to beat Mads Hermansen with a close-range header.
Having won the last five home H2Hs in the PL, West Ham looked to up the ante before HT, and their pressure was duly rewarded in the 42nd minute when Bowen’s inswinging delivery was brilliantly headed into the far corner by Mavropanos.
The excitement continued into the early stages of the second period, as both teams struck the woodwork in the space of just 60 seconds.
First, Angel Gomes curled a free-kick agonisingly against the post for the visitors, before Bowen cut in from the right flank and thundered an unerring effort against Sá’s upright.
Not to be denied, West Ham doubled their lead in the 66th minute, as Castellanos combined to devastating effect with strike partner Pablo, resulting in a clinical finish on the stretch from the Argentine.
Nuno Espírito Santo’s men sensed blood, and they added a third just two minutes later, with Bowen setting up Castellanos for a deflected strike that squirmed into the bottom corner.
Armed with all the momentum, West Ham remained on the front foot, netting a fourth late on through Mavropanos, who acrobatically volleyed home from Bowen’s corner to complete the scoring and lift the Hammers out of the drop zone.
As for Rob Edwards’ side, their relegation to the Championship could be confirmed as early as next weekend after a 16th winless match on the road this season (D5, L11).
Flashscore Man of the Match: Jarrod Bowen (West Ham United)
