iWorx® HPU3
32
505-035, Effective: June 30, 2015
© 2015 Taco Electronic Solutions, Inc.
Figure 11: HPU3 Controller LEDs
Status
Network
Service
Troubleshooting Tips
The table below provides solution to some common problems you may encounter.
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 information on resetting the controller using the LCI.
The fan will not cycle on after the
equipment status input alarm has
been resolved
If the controller was previously in an equipment status fault condition, the controller
must be reset before proper operation can be restored.
The fan and staged pilot relays will
not come on even though the LCI
indicates it is on.
Ensure that the controller and output pilot relay have been powered with 24 VAC and
the output has been correctly wired to the coil of the pilot relay. Also ensure that the pilot
relay has a 24 VAC coil.
The Space Temperature or Supply Air
Temperature thermistor reading is at
its maximum or minimum.
The input is either shorted or open.
The staged outputs will not come on
even though the space requires con-
ditioned air.
Is there water flow in the system? Verify the associated CCU2 or LHP2 controller are
operating and the HPU3 is a member of the controller. If there is no CCU2 or LHP2 con-
nected, then the Unit Enable input of the ASM2 must detect water flow (On).
