Instruction: Output yes if the supporting document can answer the given question. Otherwise, output no.

Input:
Question: Do you need a C wire for this thermostat?  Or can I replace a normal thermostat with this unit without running a third wire?   Also, can you set and lock temperature range? Thank you.
Document: This device works very consistently and has a very good Z-Wave communications range. It is able to communicate over twice the distance of any of the other Z-Wave devices I use. Also I have read that if you have a "C" wire connected to it from your HVAC system it doesn't rely on battery entirely for power and then acts as a Z-Wave repeater.One thing to be aware of. This replaces an older device that was programmable in and of itself without Z-Wave.
This thermostat is an outstanding value. It is easy to install, easy to include into a Z-wave network (I use VeraLite) and has a very intuitive interface. I found the manual to be very straight-forward and easy to understand. The unit will accommodate most every heat/cool system available and can operate without a common (on batteries) if need be.The display is also big and bright, which is a bonus.
The 2gig CT100 thermostat is an outstanding piece of technology that actually does what it advertises. The Z-Wave added to my house alarm system on the first attempt. Something I can honestly say I have not been able to with any other Z-Wave appliance I have purchased. The HVAC system can now be controlled from my smart phone. The large backlit touch screen is a welcome change from the OEM thermostat. Also this thermostat gives the option of running from a C wire or 4 aa batteries which are included.
I used it to replace a 1968 rotary thermostat. The instructions while sparse were detailed enough to follow and wire up. I have been using it for a month now and batteries that came with it are still over 90% charged. You can also wire it into a system that provides power and not only skip the batteries, it also works as a zwave repeater.
I was somewhat surprised that there weren't as many zwave thermostat choices as I thought and ones without any tricks to function sans the "C" wire. Then I found the 2gig CT100. I thought it wouldnt be a "gadget lover" type device as it didnt look that cool (read a la Nest or color screen) But simple installation/functionality and the sub $100 price(!) won me over.
I've been using this thermostat for about two weeks now with my VeraLite. It is very easy to set up and it connected very easily through Z-wave.With no existing C-wire, I'm using batteries. After two weeks, I'm already below 70% according to the Vera.
Works great with my safemart/alarm.com interface. It was easy to install and has all the functionality I need. I probably wouldn't bother with this if you don't have some sort of Z-wave controller interface as the controls on the device itself while functional are much more limited. It's nice that it has a battery in case you don't have the common wire so that it will work without one. I probably had this out of the box and working in under 5 minutes!
Also saving on my energy bill.I even have geo-fencing with my system so it adjusts the temp for me to save money while I'm away from home too! If you don't have a control near you to change the temp, just walk over and use the touch screen panel on the unit and make your change right there on the panel.I truly do not have any cons for this unit at all. Wire the power in if your system allows, but it works fine on batteries too.
Works just as expected. I'm able to beat Nest function with my Z-Wave system and scheduling. A very worthy upgrade if you have a Z-Wave system.This unit is also designed to handle just about any type of Central Heat / Air Conditioning combo you can throw at it. Very versatile. I'm only using it for an older central air system and it's working exactly as we need it to.
I wanted to be able to set the temperature at my condo before guests arrived, and set it back again after they left. This product, along with a VeraLite Controller worked perfect for my needs.Only thing I've noticed: my guests sometimes have difficulty figuring out to tap the up/down arrows on the screen to change temperature. they keep wanting to hit the 'Mode' switch.Overall the installation went fine, even on my oddly-wired Heating/AC unit.
Answer: yes