Installation and Maintenance Manual

84 VAV-SVX07A-EN
Troubleshooting
VAV Proportional Hot Water Failure Troubleshooting Procedures
Check binary outputs
WARNING
Live Electrical Components!
During installation, testing, servicing and troubleshooting of this product, it may be necessary
to work with live electrical components. Have a qualified licensed electrician or other individual
who has been properly trained in handling live electrical components perform these tasks.
Failure to follow all electrical safety precautions when exposed to live electrical components
could result in death or serious injury.
In the event that the heat outputs are not energizing, properly inspect the following:
1. Zone temperature is at or above the heating setpoint.
• Increase the Tracer™ UC400 controller heating setpoint.
2. Verify the output configuration in the Tracer UC400 controller setup screen.
• Unit needs to be configured as proportional hot water.
3. Tracer SC has the heat output disabled.
• Check overrides to make sure they are not inhibiting heat operation.
4. Heat relays have failed.
• If the Tracer UC400 controller is calling in the status screen and LED is on for binary output
to open the valve and TRIAC is not closed then check the Tracer UC400 controller TRIAC
output; wiring; and relay output.
• Check binary outputs. See Figure 37, p. 86 and Figure 38, p. 87 for correct outputs. Should
have 24 VAC; if it does not measure the power input to XFMR 24 VAC input and of the
Tracer UC400 controller. The supply voltage should be between 20 and 28 VAC (24 VAC
cataloged). However, voltages at either extreme may result in system instability.
• 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 or closed by the Tracer UC400 controller. If LED does not light up
replace the Tracer UC400 controller.
Notice:
Equipment Damage!
The Tracer UC400 controller outputs are switched to ground. Do not jumper 24 VAC to binary
output TRIAC(s) because damage will occur.
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.