The Vees found themselves trailing by a 1-0 score after the first period which saw Penticton netminder Yaniv Perets stopping a Carter Wilkie breakaway in the first five minutes of the game.
The hosts however were able to find the back of the net at the 8:48 mark of the period to take the lead.
Darwin Lakoduk knotted score at one apiece just under five minutes into the middle frame and O’Brien scored his 18th of the season a few minutes later to put the Vees ahead; a lead they would not relinquish.
Drew Esler’s first goal of the season at 9:54 proved to be the winner with assists going to Carson Kosobud and Jack Barnes.
Esler was playing in only his third game of the season after missing over a year of hockey due to injury.
The Warriors weren’t about to give up however as Evans scored his second of the game just over 30 seconds later, but that was as close as they would come.
O’Brien on the power play and Tyler Ho each connected before the end of the period to salt away the victory.
Perets stopped all 10 shots he faced in the final frame to collect his 21st win of the season and is currently third among league goalies with 2.16 goals-against average.
Vees penalty killing was perfect in the game, not allowing any goals on Warriors power play chances and scored twice on three man advantages.
Penticton outshot West Kelowna 42-29.
The Vees (36-11-1-1) will play the Merritt Centennials in the first of a nine-game, home stand Friday at the South Okanagan Events Centre (SOEC) that will wrap up their regular season.
Other home games will include, Feb. 1 against the rival Vernon Vipers, Feb. 5 against the Surrey Eagles, Feb. 7 against the Salmon Arm Silverbacks, Feb. 9 against the Warriors (2 p.m.) Feb. 14 when the Mainland Division leading Coquitlam Express will be in town, Feb. 15 against Alberni Valley Bulldogs and the final two games, Feb. 21 and 22, against the Wenatchee Wild.