for the uninitiated pit controllers such as the BBQ Guru, Stoker and Pitmaster IQue have been around some time and they basically help control pit temperature by controlling the airflow into your pit. some of the top end models have loads of bells and whistles on them such as remote monitoring and control, others are simply set it and forget it devices.
As they're quite pricey to buy, I've decided to build one and I'll update this thread as I do to help anyone else who wants to do the same. Ok this is nothing new or creative, you can find numerous examples of people making their own pit controllers around the web. But as ever the info is very US centric and I hope the info on here will help UK-based people to build one.
At the moment I'm waiting for my parts to arrive which may be as long as three weeks so all I can start off with is giving you an initial parts list.
So far I have ordered:
1. A Pid controller from eBay, it's coming from China and it's a very basic 12V DC model but comes with a K-type thermocouple. It makes sense to buy a 12V model as your whole circuit is going to be in 12V DC.
2. A DC solid state relay from eBay, this is not strictly necessary as the PID has a relay output, but by adding my own ssr I can use the relay output on the PID as an alarm sounder.
3. A 12V DC blower, similar to those used on PC graphics cards. I have ordered a 50mm fan which pumps out 20CFM, as I'm running this on a 18.5" WSM I may need to lower the fan speed, but this can be done quite easily.
4. Some 1mm sheet aluminium that I'll use to make the blower adapter. 1mm is thin, easy to cut and form, and given the shape of my blower adapter, will hopefully be robust enough. If not I'll have to buy some thicker sheet
5. A stainless dog bowl, this will be the part of the blower adapter that attaches to my WSM.
6. Some switches and a DC sounder from Maplin, I plan to have a master power switch, alarm disable switch and blower disable switch (for when I have the lid off).
I still need to buy a case to put it all in and all the required fixings. But so far I've dropped £30 on it and don't expect to spend more than an additional £10, bearing in mind I'll scavenge a power supply.
As and when the bits arrive, I'll post some pictures of them under each list item above. Interestingly, the electronic version of the manual for the PID I've bought actually includes examples of using it as a forced draft system, complete with recommended PID settings so they should be a good starting point when it comes to tuning it.
More updates to come...