As mentioned in the "How do i use a Traeger?" topic on "Help & Advice", I recently posted an idea on PelletHeads. Although the responses I got were both helpful and interesting, they mainly seemed to address other ways that I could achieve what I was talking about (either buy a digital controller, or a Stoker with a DPDT relay), rather than my suggestion itself. Or maybe that is sour grapes on my part, 'cos no-one said "That's Brilliant"!
The whole idea is to allow me to play about with the Traeger, *without* spending lots of money, or permanently changing my Lil' Tex. Now that winter is over, I'm actually getting on fine with the 3 way controller, but I like tinkering; and it may be even colder next year!
The idea revives around an X10 home automation module that I have already sitting in my spares box. This means the initial part of my idea will be zero cost. The X10 module is a 240V on-off switch (not a dimmer), which can be controlled by signals sent over the mains, either from a control switch or (more interesting) from a computer.
Using the appropriate Molex connectors, I thought of installing by-pass wiring so I can either use the 3 way switch, or have it controlled as follows:
1) Hot rod still controlled by 3-way controller.
2) Fan always on (i.e. controlled by 3-way controller).
3) Auger controlled by the X10 module.
This will allow me to use my computer to control the timings of the auger, and with a simple script, have any combination of on/off timings that I like.
For instance, I think the standard 3-way switch uses the following settings, on a 4 minute cycle.
Smoke: 1 min on, 3 mins off
Med: 2 mins on, 2 mins off
High: Always on
Controlling the auger from a script will give me the ability to have settings between these. For instance, if it is cold out, and Smoke is not getting up to temperature, I could have 1.25 mins on, 2.75 mins off. (I would also probably use a shorter cycle, replacing 1 min on/3 mins off with 15 secs on/45 secs off.)
It still won't be temperature control, but it would give me much finer control. If I see the temperature is climbing on my MT73, I just tweak the on/off interval. More to the point, most of my smoking is done while I work from my office upstairs (in front of a computer). So changing a setting on my desktop, that sends a signal downstairs is much more convenient than running downstairs when I see the temperature is not right.
All of the above I can do for the cost of a couple of Molex connectors.
The possible (but not obligatory) second stage of the plan would be to find a way of getting the grill temperature into my computer. This may mean buying a Stoker. I would then need to see what info the Stoker gives me, and how I can adapt it to control my script. However (and this is the important bit) the Stoker will not be turning the Traeger auger (or fan) on and off. It will be telling my script what the grill temperature is, allowing the script to determine which cycle is appropriate to use. So rather than it being an on/off scenario, it will be a question of changing from 15 secs on/45 secs off to 20 secs on/40 secs off.
Hopefully this would avoid the violent temperature swings I have read about when trying to automate temperature control on a Traeger.
What do people think, am I insane? For the moment, I would appreciate comments on my specific idea (even if it is "it won't work, because...") rather than alternate ways of doing this. One of the benefits of my suggested method is that I can experiment with whether my basic timing method works before spending any money on a Stoker, or alternative. If the script doesn't work while I am controlling it manually, I can simply write the idea off.
Note that I programme in perl for a living, so the complexity of the script will not be an issue.