Hello all --

First time poster here, so go easy on me ;0

I'm a homeowner with a single stage zoned system, with one master thermostat and two slave thermostats in a town-house style condo. The thermostats are wired through an EWC-ST-3E UltraZone control panel [1], and I have an American Standard Freedom 90 Single Stage Condensing Gas Furnace [2] and American Standard Comfort Coil (Universal Heat Pump)[3]. The system is essentially wired up basically the same as shown in this 6-wire zoned configuration on the RiteTemp site --
http://www.ritetemp-thermostats.com/zoned.html -- except that slave thermostats are connected to the G fan relay, so they're 4 wire instead of 3 wire like the diagram shows.

Currently, I have a lower-end Robertshaw 9400 thermostat for each zone [4]. I'd like to switch to higher-end programmable thermostats w/ auto-changover, etc. I've been researching products to see which will work with my system, as I know that the zoning puts some restriction on which thermostats will work properly. For the master zone, I'm looking at the list of stats I mention in the thread subject -- the Honeywell VisionPro, White Rodgers 1F97-1271, RiteTemp 8082c and Lux SmartTemp TX9000TS (pro PSP711TS has auto-changeover). My ultimate goal is basically a set-it-and-forget-it type system with maximum fuel efficiency / comfort. I also would like to have additional features like a remote outdoor temp sensor, battery backup, filter replacement reminder, humidistat (just a read-out of indoor humidity as I can't control my EWC humidifer remotely).

I've scoured product documentation for each of the products, and I've even sent inquiries to the manufacturers of the thermostats and the zoning panel. But some haven't responded, and I still have a couple of questions that I'm hoping one of the experts here can help with:

- It appears the VisionPro will *not work* with my zoned configuration. I only see one connection for a single O or B wire, and I know that my master stat *must have* both an O and B that energize on heat and cool for my system to work properly (with the dampers and such). Product documentation makes no mention of zoned systems. I know this thermostat is a definite favorite here and would likely be my first choice if it worked properly. But I don't think it will -- can someone confirm this?

- I'm having trouble determining if the White Rodgers stat will work in my configuration. There are terminals for both O and B on their stats, but there really isn't mention on their site of zoning compatibility. An inquiry to their company a few days ago has gone unanswered. Can anyone confirm compatibility with zoning on this stat?

- Lux got back to me and told me their stat will work for the master zone, but not for slave zones. They also told me I need the pro version of the stat for auto-changeover, which makes the WR look more enticing. Do they have a good reputation for reliability / quality product (I'm guessing probably not since they seem to be a bit bargain priced)?

- The RiteTemp seems like it will work -- but I get the impression these stats are looked upon quite unfavorably by the industry in general. I assume this should be a last resort if I'm desparate for a touch screen?

- Can someone recommend a solid / reliable thermostat for the slave zones that might not be as costly as the touchscreen one for the master zone, but that still offers full 7 day programmability to match the master stat and some of the other nice features like humidity, etc?

Thanks in advance for anyones assistance.


[1] http://www.ewccontrols.com/ultrazone/st_panel.htm
[2] http://www.americanstandardair.com/P...erCategoryID=1
[3] http://www.americanstandardair.com/P...erCategoryID=1
[4] http://www.icca.invensys.com/robertshaw/9400spec.htm

[Edited by iristyle on 04-18-2006 at 01:04 PM]