Voracek made it 3-0 with a power-play goal at 10:35 of the first when his shot from the right side went off Beauchemin's stick and past Smith.
"First period, we come out and weren't physically ready to go," Avalanche coach Jared Bednar said. "We were on our heels and we let them come at us. We weren't prepared for it. Kind of tough luck on a couple of those for Smith, but we brought that on ourselves."
Weal scored at 7:16 of the second period to give the Flyers a 4-0 lead. The goal was upheld by video review after Bednar challenged that Philadelphia was offside.
It's the first time the Flyers scored more than three goals in a game since Jan. 12. In their previous 11 games, they had 17 goals.
"It's fun," said Giroux, who had his first multipoint game since Jan. 14. "Guys have been working hard as a team, but lately we haven't had the results and it's been frustrating. So we have to keep working at it, keep working as a team. It moves a little better now that we have a win. So let's keep her going."
Avalanche forward Mikko Rantanen was awarded a penalty shot at 5:13 of the second period after being hooked by defenseman Radko Gudas. On his attempt, he skated through the right side of the Flyers zone but lost the puck before he got off a shot.
Colorado was 0-for-4 on the power play.
"If you don't score any power-play goals and you get some chances, it hurts," center Nathan MacKinnon said.