Step 2: Building the Servo Mount & Electrical Schematic

Here's a video overview of how to build the servo mount and the schematics of the electronics. Check out the photo's below for more!

<p>Thank you for sharing this information on how to use a temperature thermostat controller. I think this is pretty neat, and would be nice to have. <br><br>Dorthy Packer | &lt;a href='http://www.romaniukheatingac.com/about_us.html' &gt; http://www.romaniukheatingac.com/about_us.html&lt;/a&gt;</p>
<p>Thanks for the great Instuctable -- 5 years later and it's still relevant! I used your code for a slightly different purpose however. I have no outside space (another NYC problem) so I built a window greenhouse for my herbs. Temperatures can reach 100&ordm;F plus in there on sunny days and I wanted a means to open the lid automatically when it gets too hot. In comes your project. I tweaked the code to work with DC motors instead of servos, added a couple of options, and it works like a charm. No more wilted herbs. Now I'm considering adding an 2 line LCD to show the current temperature.</p>
Wanted to post my thanks for a very thorough and useful Instructable. I have 2 similar A/C / Heating units in my apartment and used your walk-through and code to create my own setup. <br> <br>My units only have 1 on/off switch so I used 2 micro-servos instead and tweaked your code a bit to work with them. <br> <br>Have you posted this code up to GitHub or any other code side? I would gladly branch and check in a commit if so. <br> <br>Many many thanks for taking the time to put this together!
Thanks so much for posting this! This made it so much easier to fix my <a href="http://www.manwill.net" rel="nofollow">hvac in slc</a>.
This is great i will totally be able to make my own <a href="http://www.perfectionheating.com" rel="nofollow">hvac st paul</a>.
Wow, this is a lot more complex that I anticipated. I live in Florida and anyone from here knows a good <a href="http://www.aaaeinc.com/hvac.html" rel="nofollow">hvac</a> is key to your home. I might just get some expert help but try my best to do it. Thanks for sharing this info!
My friend just got an <a href="http://www.appliancerepairscincy.com/system-repair2" rel="nofollow">hvac in Cincinnati, oh</a> and loves it, but he has been having a struggle with the thermostat. I didn't think there would be an instructable for it, but I'm glad there is! I think this will really help him out, thanks for sharing.
I had no idea that I could make a <a href="http://www.discountheating.net" rel="nofollow">hvac</a> controller like this. I really want to build this soon. With winter just around the corner, I think that I will be changing my settings a lot until I find a temperature that works for my home. Thank you so much for this great guide!
i have a ge wallthru model AJJ09DFV3 and the controls are not push button but turning controla.. 2 of them , one for hotter or colder 1-10 and the other for heat a/c low and high and fan only.. Any suggestions? Thank you
I&nbsp;did something close last year but in my car instead.<br /> <br /> Like your AC the car is either on or off.&nbsp; <br /> <br /> I used a relay and temperature sensor and&nbsp;a PIC micro.&nbsp; Later i added a pot and display to be able to dial in my settings.<br /> <br /> Interestingly, my gas milage went up as a result.<br /> <br /> Great things there micros.<br />
For our A/C systems with remotes,I'd probably get a remote and control that with an Arduino xD
Hmmm...how you say in English...my Engrish not so good...BALLIN!!!!!!!!!!!
Outstandingly explained! However do be careful about fluctuating heat/cold, but i bet you also factored than into the equation given the detail of this instructable 5/5
Very nice instructable! Well written and explained, also the device is cheap and easily constructed. I especially like the "tread lightly, leave no footprints" approach to modifying rented property. I always try to modify something in a way that doesn't permanently damage it so I can reverse what I've done if it doesn't work to my liking or restore it to original operation if/when I need to sell it or return it to its rightful owner. Yours fits right in with that kind of philosophy. For that you get a "5"!
An alternative to the One Wire Digital temperature probe is a LM35 precision linear temperature sensor. They are cost about $1.75 from BGmicro or Jameco and require only one line of code to read the temp from an analog input pin.<br/><br/>An example of a project that uses the LM35 sensor can be found here.<br/><br/><a rel="nofollow" href="http://solderintheveins.co.uk/?p=298#more-298">http://solderintheveins.co.uk/?p=298#more-298</a><br/>
This is so useful!! I can't wait to install one in my apartment as the weather gets warmer!
I can't believe I just spent a half-hour watching a how-to video! But great job. Definitely a plus that you didn't wreck the original control panel! Too many don't respect others' property. I recently bought an Arduino, and these simple how-to videos are great. This is just what an Instructable should be: relatively cheap, easy to grasp, and useful.
(OK, I'm not exactly a hands-on kind of person which is why I love, no need, Instructables so the following may be obvious to everyone but me.) I was wondering how you knew what size servos to use, and how I could size the servos I might need. I needed someway to measure the force required to operate a mechanical switch. First, I thought I could use my postal scale (up to 16 oz). I used a pencil to push on the switch then pushed the pencil with the scale bed. Not enough force. Then I hit upon the idea of using my quart water bottle, which is graduated in ounces. I needed 20 oz of water in the bottle to operate the switch. The bottle weighs 5 oz so the total force was 25 oz. (Fortunately, 1 oz of water by volume also weighs 1 oz! ) So, assuming the length of the arm on the servo is 1 inch, I will need at least 25 oz-in torque. Your servos will give me plenty of force to spare! Obviously, this method only works when you can push down on the switch.
Yes, very good instructable and well worth duplicating by other people for their comfort, lower heating/cooling costs, and lower demand on electrical resources. I had no idea so many apartments in NY had no real thermostatic control, much less programmable control. Also excellent ideas to keep it low / no impact on the original equipment. I probably would not have thought about your idea to pinch it to the top of the inside ridge. Your 'future' ideas would be well worth completing too. Keep us appraised.
Nice Instructable. Good videos also.
I made something very similar to do almost the same thing in my office. We couldn't keep the temperature constant and it would always be freezing in the morning and boiling by mid afternoon. In comes Tempy (my arduino powered servo controller) who takes temp readings every 15 secs and turns the knob on the thermostat. Good work! Here's Tempy
Thanks everyone for the kind remarks. I readily admit that not everyone has a need for this Instructable - but there are still millions of these types of units (non-thermostatic and non- energy star) out there! Anyways, my hope is that people will learn from it and possible expand it for similar benefits! I've entered myself into the Epilog Contest; I run a single-person machinist / rapid prototyping shop in NYC and am trying to expand. A Laser Cutter would be a huge asset to my shop. FWIW, I do a lot of free work for folks who are trying to get experiments or prototyping off the ground (I also maintain a day job to pay the bills). Accordingly, I would very much appreciate your vote (which I believe starts Monday 4/20). Thanks!
You removed the 3rd video?
No idea why that happened; i just placed the link and it appears to be working now
I have no need for this device, but I commend you on your instructable. I'm a big fan. Thanks for being thorough.
Wow, nice job! Elegant and effective.I love how it doesn't require any modification to the HVAC unit. Great for dorms.
This is really excellent! At first (just from the title and icon) I thought it was going to be a marketing spam. I was completely wrong! You've provided a wide variety of sources for the components (rather than the "you can buy everything from us!" I was expecting). With detailed instructions, pictures, and the videos, you've created something that should be reproducible by others. Congratulations.

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