Your budget is enough. I usually take help from social site in my product marketing. I am sure socail site will help you in your marketing.
Michael is correct. Clickbank only deals in products that can be digitally downloaded. If you have a PDF manual and video on how to build your controller then you might have yourself a Clickbank product. If you have a good product, that is not infringing on an existing patent, then I would check out some distributors (in the heating control market) and see if you can strike up some kind of deal with them. They will do the selling for you for a small commission, and they will market to that very specific consumer audience.
Affiliate marketing is definitely a viable and cost-effective tactic, although setting up the system can be a little difficult. You may want to go with a ready-made solution like Ebay, but what I recommend if you have the budget is setting up your own affiliate system, and attracting your own affiliates.
Well you can play around with Pinterest to see what type of response you get to the product and just go from there.