The victory, which saw the home side score five tries, means Jim Mallinder’s men are now just two points behind fourth-placed Harlequins in the Aviva Premiership standings.
And they have the bit between their teeth with 10 regular-season games to go, with the confidence now coursing through the veins of the men in green, black and gold.
They had claimed a stunning last-gasp victory at Harlequins seven days earlier, and they never looked likely to leave it as late against Irish.
Saints were in control from the off, with their forward power proving too much as James Craig, a penalty try and an effort from Alex Waller put them 21-0 up at half-time.
And with the hosts determined to run the ball at every opportunity, the backs chipped in with two fine tries, with Jamie Elliott and Lee Dickson dotting down in style.
Stephen Myler finished the day with a 100 per cent record from the tee, landing 10 points.
Irish eventually scored through David Paice, with both JJ Hanrahan and Jamie Gibson sent to the sin bin late on.
But it mattered not, as Saints sent their fans home happy.
Mallinder’s men had not produced anywhere near their best form at the Gardens prior to this game, scoring just seven tries in Northampton.
But they were boosted by their fine win at Quins and with the official opening of the Barwell Stand producing some pre-match fireworks, they were determined to impress.
Burrell had been one of the stand-out players at The Stoop and he picked up where he left off as he carried into the heart of the Irish defence, pushing the away side back early on.
Irish were struggling to cope as Burrell helped earn a penalty and visiting prop Halani Aulika was sin-binned for stopping Saints taking it quickly.
Burrell was rampant and after he nearly sent James Wilson over with a clever kick, Saints went to the corner from a penalty, giving Craig the chance to drive over.
Myler converted with aplomb and he was soon adding the extras to another score as Irish again failed to deal with the power of the home pack, forcing referee Tim Wigglesworth to award a penalty try.
Aulika returned to give Irish a full complement again, but they had plenty of work to do at 14-0 down.
They could have closed the gap after some good work over the ball won a penalty, but Shane Geraghty dropped his kick well short of the posts.
The game had got a bit scrappy since Saints’ second score, but the home side tried to up the tempo once again before the break.
And the managed to, with some patient play through the middle eventually seeing Elliott hand Waller the chance to walk in unopposed.
Myler landed the conversion with the help of the left post, meaning Saints held a commanding 21-0 lead at the break.
Irish started the second half on the front foot and should have scored when Geraghty broke free, but his final pass was snaffled by Myler and Saints survived.
And it wasn’t long before the home team were back at the visitors’ door as a clever Dickson chip over the defence saw Elliott beat Geraghty to the ball to score.
Myler’s conversion made it 28-0 and Saints were soon registering another score, which was a contender for their best of the campaign so far.
Tom Wood broke clear before Burrell and Jamie Gibson combined to tee up Dickson for a stunning effort.
It got the Gardens faithful on their feet, bringing the buzz back to the ground after some stodgy home games this season.
Myler added the extras once again to maintain his 100 per cent record from the tee and with 30 minutes to go, it was getting really ugly for Irish.
Saints were running from their own 22 at every opportunity and they were causing Irish problems at every turn.
So comfortable were the home side that they turned to their bench to give players a welcome breather, with Mike Haywood one man coming off early.
Reece Marshall came on for his Aviva Premiership debut at hooker, while JJ Hanrahan and Ethan Waller were among the others introduced just 15 minutes into the second period.
Irish tried to restore a semblance of respectability as they mounted some late attacks and Hanrahan was sent to the bin with 10 minutes remaining.
And Gibson was soon joining his team-mate, meaning Saints were down to 13 men with four minutes to go.
Irish finally made them pay as hooker Paice dotted down, with Geraghty converting.
But it made no difference as Saints celebrated a fine victory that means their chances of reaching the play-offs for a seventh successive season are very much alive.
Saints: Foden; Elliott, Burrell (Pisi 67), Mallinder, Wilson; Myler (Hanrahan 55), Dickson (Kessell 61); A Waller (E Waller 55), Haywood (Marshall 55), Brookes (Denman 60); Craig, Day (Matfield 60); Gibson, Wood, Dickinson (Harrison 50).
London Irish: Fenby; Ojo (Brophy-Clews 52), Mulchrone, Williams (Waldouck 61), Hearn; Geraghty, Steele (Allinson 40); Court (Smallbone 48), Paice (Ellis 48), Aulika (Halvatau 61); Symons, Lloyd (Nagle 59); Sinclair, Narraway, McCusker (Treviranus 73).
Referee: Tim Wigglesworth