Trane VAV-UCM 4.2 - Trane;Honeywell Proportional Valve Check out Procedures; Cartridge Failure; Actuator Failure; VAV Two Position Hot Water Failure

78 VAV-SVX01C-EN
Troubleshooting
Trane/Honeywell Proportional valve check out procedures
Two problems can occur with the cartridge/ actuator or both that can result in over conditioning the
space.
Cartridge Failure
• If the actuator is driven closed but there is 1/8" or more play in the indicator (move with your
finger), or the piston has not returned up past the A port or has "frozen". In either case, the
cartridge is not closed off completely. This will result in over heating (or over cooling) in the
space.
Actuator Failure
• If the actuator has stopped moving to the closed position when commanded to, and there is no
play in the lever, the actuator has failed.
• Remove the actuator and work the cartridge stem manually. If the stem moves freely, then only
the actuator has failed. If the stem is sluggish or stuck, the actuator and the cartridge have failed.
Note: Actuator indicator on the side of the actuator should be positioned at the top of the actuator
when valve is closed.
VAV Two Position Hot water failure
Check binary outputs
In the event that the heat outputs are not energizing, properly inspect the following:
1. Zone temperature is at or above the heating set point
• Increase the UCM heating set point
2. Verify the output configuration in the UCM setup menu
• Unit needs to be configured as two position hot water
3. Tracer Summit has the heat output disabled
• Check group, global, and/or Tracer overrides to make sure they are not inhibiting heat
operation.
4. Heat relays have failed
• If VAV UCM is calling in the status menu for the valve to be open and it is not then check UCM
Triac output, wiring, and Relay output.
• Check J6 to TB1-2. Should have 24 VAC; if it does not, measure the power input to TB1-1
(power) and TB1-2 (ground) of the UCM board. The supply voltage should be between 20
and 28 VAC (24 VAC cataloged). However, voltages at either extreme may result in system
instability.
Notice:
UCM Outputs are switched to ground. Do not jump 24 VAC to J9, J10, or J11 because damage
will occur.
• Heat Triac(s) can be checked with purchasing a 24 VAC LED and see if it lights up on call for
heat output to be open by UCM. If LED does not light up replace UCM.