Another newbie vacation home question

Oh, one more thing to add. My HVAC system is Trane dual fuel sysem. Heatpump and propane. I don't know if a special TS is needed for that.

Also, I have access to an extra PC if a console solution isn't available, although I would probably need to get a UPS for it.

Jeff

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OK, you'll need two things: a controller that you'll be able to dial into, and a thermostat system supported by that controller, preferably without having to run new wires.

I would recommend the Elk M1 Gold

is a nice, relatively inexpensive controller with built-in voice menus (it also does security and lighting too, but you can ignore those features). The thermostat interface add-on supports a few thermostat systems, but I would recommend the RCS TR16 or TR40 because it can use your existing wiring. The RCS thermostat is a two-piece set containing the wall display unit which uses the existing thermostat wiring to communicate to the control unit, which in turn is controlled by the Elk.

There is a cheaper way: an X-10 telephone transponder + the X-10 version of the RCS thermostat, but it is not likely to be as reliable so I wouldn't recommend it.

- Mark.

Mark, thanks for the advice! It looks to be a pretty powerful unit. If its reliable, its worth it, but it looks like the majority of features is to support a security sytem which would be a bit of a waste for me, unless it was able to do other thing such as track outside temperature and could use for programming. As an example, if I'm getting in late at night and the afternoon temperature is 50 and is going to get down to 20 by the time I get in, I'd probably want it to start heating the house earlier since the heatpump would be more efficient at 50 compared to blasting propane at 20 degrees. If the outside during the day is 20, and is going to be 15 when I get there, I'd probably have it start an hour before I arrive. It would be nice to program a system to figure it out by itself, but in all candor I'd probably just dial in and bump up the temperature.

I agree, the x10 wouldn't be reliable enough. I've had some bad experiences with some of the lamp modules, and have read others that have had intermittent success. I wouldn't want to risk being away for a month and having the system go belly up and freeze all my pipes.

Thanks. Jeff

experiences with some of the lamp modules, and have read others that> have had intermittent success. I wouldn't want to risk being away for> a month and having the system go belly up and freeze all my pipes.>> Thanks.> Jeff>

Your wiring requirements would seem to be a severe restriction but here's a suggestion:

Look into the Aprilaire (was Enerzone and Statnet) communicating thermostats (model 8870). I've used them for about five years and can recommend.

They would solve your wiring problem in a way that you may not have thought of because they accommodate remote sensors. You can physically replace the existing thermostat with a sensor at that location, which in turn would be connected to the thermostat at a remote location by the _existing_ wiring. The T-stat can be any where you can route wires including at the furnace/boiler where the existing wires presumably now go. The thermostat itself can be controlled by a home automation program or system for set-back and monitoring (Homeseer, Elk, CyberHouse, Premise Systems and soon, Charmed Quark).

The Aprilaire/Enerzone thermostats also have the virtue that the ASCII command set is straight-forward and you can control them from a simple communication program such as hyperterminal.

So, assuming 24x7 internet connection, you can connect from home to a 8870 T-stat at your vacation home through a TCP/IP--> RS232+ RS-485 converter (Comtrol, Lantronics, etc) directly though an inexpensive router/hub _without_ having a local computer running or a local home automation controller (Omni, Elk) connected.

Hope This Helps ... Marc Marc_F_Hult

1) A local controller (at the vacation home) is not required if one uses a communicating thermostat connected via TCP-IP--> RS-xxx converter via the internet. The original poster states that he has 24x7 internet connection so seems completely practical in his case. Optionally, the thermostat at the remote location (vacation home) could indeed be connected to a controller at one or more different locations. This ability has been a feature of Savoy's CyberHouse (no longer available for new sales) since at least 1999. As I understand it, Charmed Quark has/will soon have the ability of a local instance of the software running on a local pc to control devices connected to serial ports on a remote pc connected via the internet. 2) All communicating thermostats that I am aware of *do* require one to "run new wires" if, as in the original poster's case, AC and spare low voltage conductors are not available. So one actual solution to the OP's problems is using the existing wiring to connect a remote sensor to a T-sat that can accommodate a remote sensor and to move the T-stat to the other end of the existing wire (or an extension to it).

See also my other post on this topic.

Marc Marc_F_Hult

Yes, you should use a 2-stage thermostat with an outside temperature sensor. The Aprilaire 8870 previously suggested is such a thermostat but it needs to be programmed to set the balance point.

If you can set up your pc to be remotely controlled over the internet via XP's built in software, MSTSC, pcAnywhere, or VNC ( ; you can manually control (i.e., read temperature and change set point) an 8870 with most any terminal program such as Hyperterminal that you probably already have installed if you use Windows. You would also need an RS-232 --> RS-485 converter (Available on eBay for about $15.) and the ability to route through your router/firewall to the required port address. Most SOHO routers can be configured to do so.

... Marc Marc_F_Hult

I believe my Trane system handles the changeover from HP to Propane automatically. The zones are controlled by a zone board. Theoritically I think a regular thermostat (independant of fuel determination) would work, but I need to check with my air guy. Thanks again for the useful info.

My daughter's boyfriend's dad runs an AC business so he can probably tell me if its safe or not. I'm a EE by education, but I know better than to hook up the wires without making sure. That system has more electronics than my car - especially with that zone board. FWIW, I say this based on my lack of knowledge, I'm not doubting your advice.

On a side note, eventually I'd like to have a PC there to capture web images from a web cam and upload stills or streaming to my website.

So that heating system has a way of sensing and acting on the out \\side temperature. That's what is needed.

On a side note, eventually I'd like to have a PC there to capture web

PC's are fun ;-) but just as with the thermostat, you can set up an IP connection through a router to an IP device (in this case an IP camera) and dispense with the PC.

HTH ... Marc Marc_F_Hult