Johnson a419 controller

Can this controller be setup to control heat and cooling together or just one or the other? I have it setup in cooling mode now but need heating at night and possible cooling during day. I am thinking of wiring a heat belt for night but want to keep cooling for daytime. Thanks

Just heating or cooling. I built a very small heat source (4W) out of a pair of resisters and a 9V power supply that maybe raises the temperature of 5 gallons 1F-2F per day. I leave that in the freezer running all the time (with a PC fan circulating the air) only when I want to run the freezer above room temperature but still in cooling mode to limit an heat generated during fermentation.

That method will only work when the ambient doesn't drop too much lower than the setpoint (5F-10F).

When fermentation is over and I still want to maintain temperature above ambient, I switch the A419 to heating mode and run a bigger heater (8W-15W).