1) RDA build with 22awg. 20 and 22awg stay hot long after being fired, heat is disapated down into the 510 connection, out across the top plate of the mod
2) RDA build resistance, thought the Sig150 is rated for 0.1 ohms and above, like stated above, high wattage it likes 0.3 to 0.5 ohms
3) Because of the RDA build and wire gage, taking a tremendous amount of current to ramp up those coils, more amps required flows through the whole mod, the mod body is part of the negative ground circuit path
4) Because of amp draw on the batteries, they warm up, and like the wire in the RDA take time to cool back down to room temp again, this radiant heat is transferred to the mod battery door, bottom plate, and top plate, back plate is insulated by plastic in the battery tray
I find if I am chain vaping, even in the range of 8 to 14 watts depending on my tanks that range in 1.2 to 1.8 ohms, just from electrical conduction, any of my mods gradually get warm after about the 15 hit mark. My mechs, Sig150, and IPV3 when using my RDAs in the 40 to 80watt ranges, after about 5 hits my mods get warm rapidly.
Nature of the beast when dealing with anything electrical.
