Calgary won for the fifth time in its last six games. Alex Tanguay had two assists against his former team while Tony Amonte added a goal and two assists. Kristian Huselius scored two goals and added an assist.
The Avalanche had five power-play opportunities through two periods and scored on three with Calgary scoring short-handed goals on the other two.
The Flames broke the game open with three unanswered goals to begin the second period, including two by Langkow - his 17th and 18th goals of the season - within 1:51 of each other. They scored a season-high four goals for a period in the second.
Calgary goalie Miikka Kiprusoff finished with 27 saves.
Joe Sakic had three assists for the Avalanche.
Colorado pulled Peter Budaj at the 12:05 mark of the second period after he gave up his fifth goal of the game on 17 shots. Jose Theodore, who was booed as he skated on, gave up two goals on nine shots. Theodore hasn't played since being pulled on Dec. 27 against Dallas after giving up five goals.
Paul Stastny and Marek Svatos scored power-play goals for the Colorado in the first period.
Jarome Iginla missed his third game since spraining a ligament in his left knee against Florida on Jan. 4. Iginla is leading the Flames with 53 points and 23 goals.