Monitoring temperatures from afar can be a challenge, and controlling HVAC systems even moreso. Commercial solutions do exist - at a great cost, and generally rely on having an Internet connection. However as long as there is mobile phone coverage, you can have your own system that can be interacted with via SMS in order to control climate systems, get remote temperatures and set other paramaters. The method of doing this has been documented by Instructables user "kohleick", whose system is complete and works well.
The system uses numerous temperature sensors, a real-time clock, LCD and buttons for a local control panel, relays to control the heating and a Siemens GSM modem for remote interaction. The display below is an example of the local user interface:
This is a great solution to a problem, and also a fine demosntration of adding SMS control to an Arduino-connected device - so check out the project Instructable to get started. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
To get started with your own temperature-controlled projects, consider using our TEMP: DS18B20-based temperature sensor module:
... or our HUMID: Humidity and Temperature sensor module based on the popular DHT22 sensor unit. Both modules are fully documented and easy to get started with. These are only two of over a dozen of our sensor and outputs modules.