I work at a distributor and we carry the EcoBee. It is an excellent product for vacation home monitoring. It is set up like any typical TStat. Your home also needs Wi-Fi (a router) in it for the TStat to have its functionality. There is an IPone App, and also any internet connection can be used to adjust temp, check the temp, or other items monitored with the stat. It has a couple of extra switches that can be set to things like a wet switch in a basement, or an open door sensor (it can't control them, but can read them). This stat can also be set up to send you an email if the temp hits certain pre-set conditions. So you can have it email you if the temp in your lake cabin hits 40 degrees, (Before the pipes freeze) . It can email you if the basement wet switch goes off, or if the door is open. You could have it email a local HVAC dealer or caretaker as well. And you can use your IPhone like a remote. If you are in bed, and want to make it warmer, pick up the phone from the bedside table and adjust it from where you are. Their website is excellent if you want more info. It is kind of expensive, but here are no additional monthly fees.

Update: Because neither I nor the HVAC guy could get the Honeywell 9000 thermostat to work, I put in the Lowes Iris one. However, as discussed above, Iris's computer interface doesn't work. Meanwhile, (in July), the HVAC guy came back, with the plumbing supply company owner AND the local Honeywell rep, and they determined that the tstat was defective. Because it was a "Pro" model, it had a 5-year warrenty. They put in a new one. So, I took mine back to the store where I bought it, and they exchanged it without difficulty (even though I didn't have the receipt). So now I have two (for two zones) and the one they installed seems to work fine. I can't tell for sure until it gets cold, but checking it out as well as I could, it does work. And the computer interface is very good. I can access it from my smart phone(s) and my computers, both MAC and Windows (which the Iris couldn't do). When I originally installed the Honeywell thermostat, I called tech support and they said that since this was a pro model, the would only talk to pros. So, when the pros were here, they were able to use tech support. Even the Honeywell rep needed to talk to them!

Hi Pippipal, I think I found a remote control thermostat set up that does not require WiFi or connection to the internet. I requires a Zwave enable thermostat and a Zwave controller. The Zwave protocol use RF at a 908.42Mhz frequency. Here is a TRANE 14942771 Thermostat with Z-Wave on Amazon. You also need the GC2 Security & Control Panel. Here are two videos; How To Add A Z-Wave Thermostat To The 2GIG GO Control Panel and a second one 0:00 / 4:55 Programming a GoControl Z-Wave Thermostat into a GC2 Panel that will give you an idea how this can work. I have no experience with any of these products but hopefully they are a good solution for controlling a thermostat remotely.

Two different homes, two different models. You should be sure what your own system's needs are, as to available wires and compatible stats, before moving forward. They're not all the same. Ask your HVAC guys - the two I dealt with were more than happy to install Honeywell units because, as I said, they're the gold standard. Honeywell makes several of the private label branded stats too, the ones that the equipment companies sell with their own names on them. In one, we have two Honeywell Vision Pro 8000 series REDLINK units, because of the need to have a wireless connection from the thermostat to the furnace and AC equipment when we did a complete equipment replacement and added AC. Honeywell's REDLINK system may be the only one that offers the wireless thermostat to equipment communication but maybe not. It also offers WIFI and so internet user communications with all the normal kind of apps and even from a PC over the internet. We've had them over 5 years and the performance has been flawless and reliable. . At the other house, also with a complete furnace and AC equipment replacement three years ago, we put in one Honeywell 9000 series WIFI thermostat. The same with it too, consistent competent service. Because we split our time between these two places, it's a regular thing for us to access the stats remotely to put one in the equivalent of "away" mode, and to switch on in advance the one we're coming to. No issues ever (except for the few rare times an ISP system is down and so the the stats aren't accessible) . I know that Honeywells generally are compatible with heat pumps and aux power systems but do check in advance about what you have to be sure.