Gotcha....so I see a block 22 and also a block 22 rxt (not sure if its rxt, but has some letters accompanying the 22) is there 2 versions, or just the one?it will sense what coil you put in. if its a coil you can use for temp control, it will turn to tc when you pop in the tank and give you a recommendation for firing in tc mode. but if you put in a tank with kanthal, it will automatically go to regulated mode. im currently using ni60, it goes to regulated mode, but sometimes goes to tc.