[GRLUG] remote temperature monitoring

[Mark Farver]

On Wed, Dec 18, 2013 at 9:07 AM, desert frag <desertfrag at yahoo.com> wrote:
> Hey guys, I'm going to be gone from the GR metro area for a couple of
> months.  Do they make some type of wifi enabled remote temperature
> monitoring appliance, preferably with some type of text/email alert
> function, so if the furnace craps out I'm notified?

Just search for "freeze alarms".  They are usually telephone dialer
based so you'll need a landline or a dedicated cell phone.  Menard's
carries one or two in the thermostat aisle.

Or contract a local alarm company to install a monitored alarm system
with a freeze sensor.  This will cost a bit more but you'll gain
intruder notification.

A simple trick for a "digital" temp sensor is to use a thermostat.
Buy a 10-20$ thermostat that is battery operated.  Wire the heat
contacts to +VCC and one of the GPIO pins on a Pi or Arduino.  Set it
for whatever alarm temp you want it to go off at (55F is usually the
lowest.)  When it drops below that temp the contact close as the
thermostat tries to turn on the "heat"

It looks like a Pi has good support for the Dallas One-Wire Temp
sensors if you want to know absolute temp:
http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/temperature/


Mark