That depends on how much you pull with your props and motors - if you have flown with the same props and motors and it worked fine and didn't puff, it should not puff now. If your ESC's burnt out last time, then it may not be safe...
For a tricopter, 20C is a little low. I'd go with 30C at least, nanotech 45C if you have the bucks.
No, my escs are fine, i'm just rebuilding my frame, and bought new motors and escs, old motors were 750 kv rc-timers and 18 amp escs, new motors are 800kv NTM propdrive and the escs are 40amps, the props are 11x4,7
the 18amp escs, barely got warm when running 3/4 throttle, so i guess, they can handle the 800 kv right?
Basically using an 18amp ESC means that your motors will never draw more than 18amps each (unless they burn up!) so if you are flying a tricopter 18x3= 54.
2200mah at 20c is a max discharge of 2.2x20= 44. Therefor 20c on a 2200mah is probably not enough.
That is if I have any idea what I'm talking about..
My empirical rule-of-thumb is, if you fly it somewhat aggressively for three or four minutes and you're satisfied with the performance and after you land nothing is overly hot (<~45C), i.e., ESCs, battery or stators. . .you're good to go.