I am a bit confused when I received a free upgrade kit from Masterbuilt . My unit was well out if warranty And they stated the upgraded chip holder tray and feeder tube was re designed to prevent flare ups . I never had that issue but wondering if anyone else has and the reason ( other than a overfilled chop tray ) that a flare up would occur . I use a wide vatiety of chip types Including the Bradley pucks And my own custom mixed wood chips and never a problem . They (MES) cust service again replaced at no charge another control panel ... my indicator green led for the on /off was intermittent and the problem is common with the panels from that vendor. .