It came on the Flames seventh shot of the game, while the Pens had managed to get just one puck on the Calgary cage at that point.
Mark Jankowski - another Flame looking for his first tally of the season - had two good chances on the next shift, Jarry able to stop both.
The Flames extended their shot lead to 10-2 at that point.
The Pens got a breather and a chance to tilt the ice a bit back in their favour when Giordano was called for interference at 9:49.
They made good, with Rittich turning aside a shot from a streaking Dominik Kahun as he cut in from the wing towards the crease, but the rebound bounced out into the slot where Alex Galchenyuk wired it home through traffic at 11:49, two Flames trying to drop in front of him to block it.
Technically it was labelled even strength as the penalty had just expired, to the exact second.
Just so happened it was Galchenyuk's first of the campaign.
The Flames didn't let up, Andrew Mangiapane - who has been one of the Flames strongest players of late - getting a pass through to Matthew Tkachuk on the doorstep inches in front of Jarry, Chucky getting two whacks at it before a dog pile in the blue paint.
Bryan Rust was very nearly gifted a goal with time ticking down in the first, the puck taking a weird deflection off the ends boards and right out in front of Rittich, Rust getting a whack at it before the goalie could get his glove down to trap it, but he knocked it wide. Seconds later Rust got another shot as he circled out front but it went up and over the net.
The second period didn't start according to script, Giordano tagged for tripping Rust just 21 seconds in as the Pens forward drove the net.
However, the Flames do boast the fifth-best PK in the league, clipping along at an impressive 85.5% (Pittsburgh, worth noting, is third at 86.7%). They got the job done, allowing just three shots on the powerplay.
The Pens had some extra hop in their step after, though, piling the shots on Calgary to the tune of 10-3 to start the period. On that 10th shot, Jared McCann picked up a puck off the half-boards from Galchenyuk, skating out and snapping a wrister that deflected off Andersson and up-and-over Rittich's glove to make it 2-1 at 7:14.
Jack Johnson tripped Elias Lindholm and was sent to the box just past the midway point of the frame, giving the Flames their first powerplay.
They got some looks but couldn't beat Jarry.
They built off that shortly after with Johnny Gaudreau getting a good shot, followed by Lindholm with a chance on a rebound from a Michael Stone point blast, and then Mangiapane grabbing the puck off the faceoff and skating hard to the net, Zach Trotman tripping him from behind as he got a shot off as he fell.
Just 31 seconds into that man-advantage, the Flames hit paydirt. Sean Monahan just missed wide on a shot in the slot but got the puck back and made good on his second chance, scoring his sixth of the season from Tkachuk and Gaudreau at 15:09.
Tweet from @NHLFlames: Putting the power in power play.#CGYvsPIT | #Flames pic.twitter.com/v8y8O4dH86
That assist by Gaudreau moved him into sole possession of 12th spot in all-time Flames scoring, his 407 points moving him one ahead of the legendary Lanny McDonald.
Less than a minute later, Mickael Backlund was sent of for tripping, but again the Flames PK got the job done.
