zone damper motors keep spinning

[bhubert]

Hello,
I have an ST model board and the older model zone dampers (blue box, 3 wire, +jumper). Zone 2 blew a motor in the damper so I disconnected it and ordered a replacement new damper / motor. Now Zone 1's motors are just 'spinning' open and closed (I just noticed it today). What would cause the motors to just 'spin'?
Thanks,
B

[Eric K.]

The motors appear to be wired incorrectly. How many total zones do you have and how many total dampers do you have? Are you using more than one damper per zone?

Eric

[bhubert]

i have two dampers in zone one and one damper in zone 2. i think they are wired correctly according to your documentation.

The dampers in zone1 are not wired in series. they each are wired back to the EWC Control panel.

[bhubert]

Also, it seems that if I move the damper switch to "CLOSED" the dampers behave OK. Can I not run them with the switch "OPEN"

[Eric K.]

The dampers are wired incorrectly on Zone 1. They should not each be wired back to the panel. Correct the wiring to reflect that shown in the 'Tandem Wiring' diagram on the Data Sheet.

http://www.ewccontrols.com/acrobat/090377a0015.pdf

Eric