I have an envision gshp with an intellizone controller with 4 zones.  I've been installing a lot of Z-Wave home automation stuff in my house with the Mi Casa VeraLite Home Controller and would now like to integrate the hvac system.  Does anyone know or can recommend a z-wave enabled thermostat that's compatible with the intellizone controller?

Actually, ultimately, I'd rather not have any traditional thermostats--just temp/humidity sensors in each zone and then a software thermostat.  Hmmm,  is there anything like that out there? 

Thanks,

Thomas

If I am not mistaken the Intellizone 2 can have remote sensors and a central control panel.

Posted By docjenser on 21 Oct 2013 11:26 AM
If I am not mistaken the Intellizone 2 can have remote sensors and a central control panel.

Correct.

The Intellizone2 can control up to 6 zones.  It uses a master tstat (WF supplied) where all programming for each zone is done.  This tstat also functions as the direct Zone 1 tstat.  A remote temp sensor can be installed for Zone 1.

A separate tstat model, a zone tstat (again WF supplied), is used for zones 2 through 6.  It can be set up for setback capability, and directly 'talks' to the Intellizone2 system.

A third tstat medel is like the Zone 2 through 6 tstat model, above, except there's no user interface (touch or non-touch screen, or buttons).  It to has set back capability but it's programmed via the master tstat. 

Interestingly, it's all MODBUS technology for the communication lines - all 4 wire, 2 for power and 2 for the serial communications.

Best regards,

Bill

Thanks for the info. I have the original intellizone. Will those tstats work for that? or is it for the 2nd version only?

Thomas

Intellizone 1 is strictly 24Vac. Using any non-24 Vac thermostats or sensors would require some sort of interface or converter to handle 24 Vac.

Posted By engineer on 22 Oct 2013 09:16 PM
Intellizone 1 is strictly 24Vac.

This is not true.  There is a DC voltage presence on some Intellizone terminals, alongside the 24VAC.  This causes some tstats to not be compatible with the Intellizone 1.

Best regards,

Bill

Hmm...news to me, and I don't recall encountering that in documentation. It is perfectly possible I missed it, though. A meter set for AC in the course of debugging stat wiring might not shed light on the presence of DC. I wonder if the DC you describe is relevant to the operation of the IZ control board.

There is one DC circuit present in all two stage systems using Copeland Ultratech compressors - the solenoid that actuates the unloader / bypass is 12 VDC, but I believe the Comfort Alert controller translates the presence / absence of 24 Vac from the Intellizone board or standard multistage thermostat into the correct 12 VDC signal.

Posted By engineer on 26 Oct 2013 11:18 PM
... I don't recall encountering that in documentation.
 
... A meter set for AC in the course of debugging stat wiring might not shed light on the presence of DC.
 
I wonder if the DC you describe is relevant to the operation of the IZ control board.

There is one DC circuit present in all two stage systems using Copeland Ultratech compressors - the solenoid that actuates the unloader / bypass is 12 VDC ...

It's not in WaterFurnace's documentation.

I first discovered the problem when attempting to install a WEL manufacturer produced tstat monitoring device (WELSTAT-8) to a WF Intellizone zone controller.  The WEL tstat monitoring unit enables a WEL system to monitor up to 8 tstat control signals from a single '1-wire' network connection point.  Each channel is optically isolated from all other channels and the output 1-wire network connection.

A channel is supposed to be wired in parallel (across) whatever tstat signal is to be monitored (i.e., Y1 and C).  This enables the monitoring channel to read the same voltage being applied to the equipment being controlled.  In a 24 VAC environment, this will cause 2.4mA of current to flow through the sensing circuit.  Since this is not enough to activate a activate a relay, it shouldn't have any impact on the normal operation of the HVAC system.

But, for the Intellizone, and in some cases the Ecobee, it appears the current being drawn is enough to activate an HVAC function.  When this happens the WEL tstat monitoring unit has to be wired in series, not parallel, with the tstat control signal.

I routinely observe this situation with the Intellizone.  And one ecobee user has reported the problem to WF ("Voltage Leak - Ecobee Smart Thermostat w/ WF Intellizone Controller").

A meter set for DC will indeed show the DC presence on various Intellizone terminals.

I don't have a circuit diagram of the Intellizone to understand why there's a DC voltage presence, and, I've never posed the question to WF technical support.

WRT Copeland Ultratech: I too am aware of the DC voltage presence for this compressor's second stage signaling circuit.  And I believe this is documented in WF's materials as 'DC.' 

Best regards,

Bill