Cannot turn off smoke element with TMCC on Lionel 6-14596 Alco PA.

I have a NEW HAVEN Alco A-B-A, 6-14596. 

Engine works great. Smokes great when turned on by TMCC AUX1 9. When I use AUX1 8 to turn smoke off, the fan stops but the smoke keeps on whisping out.

I installed a new R2LC. That fixed the problem for awhile; but now the trouble has returned.

I suspect that the heating element is drawing too much power and causing the triac on the R2LC  to fail. 

Any suggestions on how to fix this so it stays fixed?

Thank you.