I'm active in NFPA and definitely not comfortable leaving something like that plugged in unattended.
My garage is insulated and stays pretty reasonable with temp extremes around 55F and 85F. Austin humidity is pretty consistent middle of the road except when it rains. No excuse for this crap.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |