Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

Page: 142 / 162

Testing the VGD actuator heater mat
1. Measure the current to the heater using either wire at the thermal switch, as shown in Figure
54. The nominal current is 1.5 A. However, it might read lower values based on the load at the
time of testing.
Figure 54: Heater mat temperature switch
2. Use an electronics safe freeze spray to lower the temperature of the metal portion of the
heater switch to energize the heater. The spray can be purchased at most supply houses. See
Figure 54 for the switch image.
3. Record the value in 160.88-CL2 .
Testing the MBC heater mat
1. Measure the current to the heater using either wire at the thermal switch, as shown in Figure
54. The nominal current is 2.5 A. However, it might read lower values based on the load at the
time of testing.
2. Use an electronics safe freeze spray to lower the temperature of the metal portion of the
heater switch to energize the heater. The spray can be purchased at most supply houses. See
Figure 54 for the switch image.
3. Record the value in 160.88-CL2 .
Testing the drive internal heater
1. Measure the current to the heater using wire 31 at 5BR on TB6 in the OptiView panel.
2. At the internal drive heater, raise the temperature control knob to a setting above ambient to
energize the heater. The nominal current is 7.3 A. However, it might read lower values based
on the load at the time of testing. See Figure 55.
YVAM Control Center 142