Temp Control

I purchased the Johnson Controls A419 module for fermnenting in my basement. The temperature down there can swing from 55-70 this time of year. (windows, park under garage etc).

I bought the Johnson thinking it could both heat and cool, but I only see one power cable to plug into. I was hoping to have something where if it get's over 68 it kicks on the freezer, if it gets under 66 it kicks on the heating element(haven't picked one out). Is this possible with this unit? In the dead of summer or the dead of winter I would be fine with one or the other, but this time of year I need both to keep consistency.

Johnson makes both single and dual stage controllers.

Not the most energy efficient thing, but there is an easy fix. Toss in a low watt heat source and just leave it on. Let the cooler be controlled by the JC and kick in if it gets too hot.

billl said:

Johnson makes both single and dual stage controllers.

Not the most energy efficient thing, but there is an easy fix. Toss in a low watt heat source and just leave it on. Let the cooler be controlled by the JC and kick in if it gets too hot.

Click to expand...

hmm. I bought this one. Is it single or dual stage? if it's single which is the dual stage?

http://www.amazon.com/dp/B00368D6JA/?tag=skimlinks_replacement-20

That is the single stage version.

I was hoping to have something where if it get's over 68 it kicks on the freezer, if it gets under 66 it kicks on the heating element(haven't picked one out). Is this possible with this unit?

Click to expand...

that programming logic itself is possible, but physically, the controler might not be able to switch both a high power cooler and high power chiller. however if you controlled the on/off of the devices with a discreet relay/SSR, the Johnson unit could take over handling the relay/SSR's control voltages.


(meaning, instead of the Johnson control directly switching the high-current heating/cooling device itself, it could instead just switch a very-low-current control signal from an external source)

But while off-loading the current requirements, ^that^ isn't going to work very efficiently under direction of a single stage controller. Presumably the relay would switch from compressor to heater with no "dead band" between.

Bottom line, the lad needs a dual stage controller. I'd recommend he either plead insanity to whomever he purchased the single stage controller and attempt to exchange it for a dual, or put the single up in the For Sale forum and spring for an economical STC-1000 to help mitigate any financial damage...

Cheers!