Need ideas to rig a thermostat to get inside/outside temp readings

**Chronus72488** · 03-18-2011, 02:57 AM

(Posted this at Centrafuse forums too, but no reply, thought I'd try my luck here...)

For all you electrical and programming nuts out there, I call upon you for help.

I was thinking of wiring up an Arduino with a 16x2 LCD module and a SHT-21 humidity and temperature sensor so I can get outside and inside temp readings of my '06 Acura RSX Type-S (No my car did not come with one from the factory, damn you newer cars...).

Some problems I see with this is primarily mounting and wiring. I don't want a bunch of wires running all over the place, and I also don't want the module to placed in a spot that would give me inaccurate readings.

With that said, anyone mind helping me brainstorm a way to make this project as lightweight as possible but still get the same functionality out of it?

**RaptureOz** · 03-18-2011, 06:17 AM

Ill be doing a similar thing soon, but utilising Phidgets Sensors, will post my progress soon.

**-zip-** · 03-18-2011, 11:46 AM

I run a Fusion Brain in my car for inside/outside temp. Very nice little board and you can do a whole lot more if you want to. They sell them here along with the sensors.

**2k1Toaster** · 03-18-2011, 04:23 PM

Originally Posted by -zip-

I run a Fusion Brain in my car for inside/outside temp. Very nice little board and you can do a whole lot more if you want to. They sell them here along with the sensors.

+1

**natemart** · 03-22-2011, 07:59 PM

I know that this is not the answer you want... But ten dollars will buy you a wireless thermometer for the house. Disassemble the housing, fab a mount, and done. Save you a ton of time. Most of them come with inside and outside readings.

**2k1Toaster** · 03-22-2011, 08:46 PM

Originally Posted by natemart

I know that this is not the answer you want... But ten dollars will buy you a wireless thermometer for the house. Disassemble the housing, fab a mount, and done. Save you a ton of time. Most of them come with inside and outside readings.

This probably wins for the K.I.S.S. methods.

Of course geeks do like their complex and unique setups which that won't gain you.

But a nice original idea.

**jmullan99** · 03-30-2011, 07:36 PM

I am using Arduino to read two LM34 temp sensors. Not the most accurate sensors (at least with minimal components) but definitely good for ambient in/out temps. I am using Open Mobile and a custom made plugin for it. The plugin uses Firmata to communicate with the Arduino. I also added code to the Arduino to compare what the two readings are and if it's cold enough, and if the car has be started remotely, it will turn on my rear defroster. Basically, if input D2 is low and outside temp is < 5c and inside is < 5c then pulse the rear defrost switch. Set flag so it doesn't keep pulsing the switch. This way, if its cold outside but the interior is already warm, no action.

Anyway, sorry for rambling. Arduino works well for me.