iWorx® MPU2
505-009, Effective: June 30, 2015
41
© 2015 Taco Electronic Solutions, Inc.
Figure 15: MPU2 Controller LEDs
Status
Network
Service
Troubleshooting Tips
This section provides remedies for common problems.
Problem
Solution
Controller is not running and Status LED is not
illuminated.
No power to controller. Verify the voltage on the controller’s
power connector (24 VAC).
How do I reset the controller?
The controller can be reset by the LCI, or you can cycle power
to the controller. Refer to the LCI documentation for more infor-
mation on resetting the controller using the LCI.
Can my iWorx® system contain multiple MPU2
controllers?
Yes, provided that you do not exceed the maximum number of
controllers that can be handled by the Local Control Interface
(LCI).
Can I reverse the minimum and maximum val-
ues for the bypass damper?
Yes. This will result in reverse damper action.
Can I use the bypass damper outputs to control
a VFD instead?
Yes.
Thermistor readings fluctuate rapidly, some-
times by several degrees.
The controller is not properly grounded. The controller’s ground
(GND) pin (T40) must be connected to earth ground.
