Zone 1 seems to always be open

[harrysiii]

Brief intro to my original system: I have 2 zones (3 dampers (using MA-ND4), 2 for zone 2 piggy-backed). I had an EWC-ST-2E configured in a Master/Slave setup and noticed that Zone 2 wouldn't work if Zone 1 wasn't on (as in set to on, not as in calling for air). Zone 1 was also blowing air whenever zone 2 was calling for air, even if zone 1 wasn't calling for air. All damper motors (MA-ND4) seem to behave correctly and as expected, as in lights on them and controller look correct, and they also turn correctly each time called or not called.

Once I was ready to install my Nest thermostats, I researched here and learned I needed an to NCM300 board and installed that. This new configuration did allow my zone 2 thermostat to work even with zone 1 thermostat set to off (removing my master/slave issue and allowing the thermostats to work), but it didn't solve the issue where zone 1 always blows air when zone 2 is calling for air.

Any ideas? Is there a way the blades in the damper are just always staying open even though the motor is behaving as expected? I haven't taken the damper out to look yet and it seems like you'll have some good information for me. I checked all my zones and none of the damper motors are set to allow for relief air.

Thanks a ton!

[Paul Z.]

Give me a call 1-800-446-3110 X490 have a volt meter ready and a few minutes.

[harrysiii]

Thanks! I'll try calling either today or later next week.