Ferrites - Lennox XC20-036-230-01 Installation And Service Procedure

VDC Voltage Check:
Check for VDC out of Fan PWM and COM. VDC output reading is determined by the percentage of room thermostat de­
mand.
1. No voltage present – Remove wires from control and check for VDC. If there is no voltage present, then replace out­
door control.
2. Voltage present – Perform a 9-volt battery test on motor (see figure 46).
STATUS OR ERROR CODES:
There is no feedback from the outdoor fan motor to the outdoor control therefore no status or error codes are displayed on
either the outdoor control or iComfort Wi-Fi
NOTE - If the outdoor fan does not operate at the correct RPM, or does not start, the system will shut be down by other
protection components such as the high and low pressure switches which will generate error code(s).

Ferrites

Electronic cabling and wires, by virtue of their length­to­width ratios, are perfect natural antennas. In the presence of
high­speed microprocessor signals, cables will conduct, radiate, and receive unwanted high­frequency signals. Use an in­
sertion-loss device, such as a ferrite suppressor as shown below, to control radio-frequency (RF) interference.
BLACK LEAD
CONNECT B4 FAN MOTOR BLACK
COMMON WIRE TO 9V BATTERY
NEGATIVE TERMINAL
NEGATIVE TERMINAL
FULLY CHARGED 9V BATTERY
Figure 46. VDC Voltage Check
®
or iComfort
Figure 47. Ferrites
BROWN LEAD
CONNECT B4 FAN MOTOR WIRE
TO 9V BATTERY POSITIVE
V
TERMINAL
POSITIVE TERMINAL
®
S30 room thermostat.
Ferrites are consistently stable over time and
over wide temperature ranges, and provide RF
suppression without causing large current
losses.
65
XC20