Lennox EL296UHVX Series Unit Information page 77

I- Proper Ground and Voltage
A poorly grounded furnace can contribute to premature ig­
nitor failure. Use the following procedure to check for
ground and voltage to the integrated control.
1 - Measure the AC voltage between Line Neutral (spade
terminals) and "C" terminal (low voltage terminal
block) on the integrated control. See figure 54. A wide
variation in the voltage between Line Neutral and "C"
as a function of load indicates a poor or partial ground.
Compare the readings to the table below. If the read­
CHECK VOLTAGE BETWEEN LINE NEUTRAL
AND LOW VOLTAGE "C" TERMINAL
W1 W2 G Y2 Y1 C C R DH L O DS
FIGURE 54
Page 77
ings exceed the maximum shown in table 1, make re­
pairs before operating the furnace.
2 - In addition, measure the AC voltage from Line Hot to
Line Neutral (spade terminals) on the integrated con­
trol. See figure 54. This voltage should be in the range
of 97 to 132 Vac
TABLE 33
Furnace Status
Power On Furnace Idle
CAI / Ignitor Energized
Indoor Blower Energized
CHECK VOLTAGE BETWEEN LINE HOT
AND LINE NEUTRAL
W1 W2 G Y2 Y1 C
Measurement VAC
Expected Maximum
0.3 2
0.75 5
Less than 2 10
C R DH L O DS