2 Homes: 3 HAI RC100B Thermostats per home: 2 Frustrated Elkers: 1 Solution?

[ph0n33z]

Alright,

Both a friend of mine and myself have the M1 and 3 HAI RC100B thermostats (oddly enough). All three are hooked up to the M1 through a single XSP. Here is the problem: I can never get all three to be seen by the ELK (2-way communication). There is always one that shows "unit not responding". My friend has tested the units and found that it isn't always the same one that doesn't respond.

Each thermostat works fine on its own. It is communication with the M1 that is the issue. Any ideas?

 

[dutchyn]

Other than the usual

• check each conductor for conductivity
• check each connection for connectivity
• check that each thermostat is uniquely addressed
• verify sufficient power to each thermostat (a common wire is the most common way to ensure this)
• compare the firmware level on the M1XSP with the current release level.

you might consider disconnecting one (the one that's most reliable) from the ELK for a few days, and see what happens. If the problem persists, remove another. Otherwise, reinstate the disconnected one, and try the next most reliable. If your friend/neighbour has an M1XSP and can live without it for a few days, try borrowing it and trying the same test, except placing the most unreliable one on the other M1XSP.

 

[AutomatedOutlet]

My guess would be that it's a RS485 termination issue. Made sure that the end of each 485 run is terminated.

 

[dutchyn]

My guess would be that it's a RS485 termination issue. Made sure that the end of each 485 run is terminated.

I don't understand: isn't the RS485 bus the one that communicates with the M1XSP? Given that the M1XSP is reporting for two of the three thermostats, I would suspect the RS232 connecting the M1XSP to the thermostats. But, as I work with this stuff, there's more to learn.