Cincinnati Sub-Zero WarmAir 135 - Page 30

WarmAir

Model 135 Manual TROUBLESHOOTING
Page 30 of 43
Problem
Possible Cause
Action
The Warming Unit turns on, but
does not blow air. Unit may
automatically trip off. (cont.)
Faulty Voltage Divider Board or
Blower
Remove the top cover. With
the unit on and in the Fan Only
mode, measure the voltage
across the blue and yellow fan
wires.
0V DC  Measure the voltage
across the blue and red fan
wires.
 If the red and blue are 0V
DC then investigate the
Power Supply Board.
 If the red and blue are 24V
DC then it is a faulty
Voltage Divider Board.
7V-9V DC  Faulty Blower.
Other  Consult with
authorized CSZ representative.
The Warming Unit’s sound
level significantly increased
during operation.
Faulty Voltage Divider Board
Consult with authorized CSZ
representative.
Remove the top cover. With
the unit on and in the Fan Only
mode, measure the voltage
across the blue and yellow fan
wires.
24V DC  Faulty Voltage
Divider Board.
Warming Unit turns on, but
temperature settings cannot be
selected.
Faulty or loose membrane
switch (switch contacts or
header).
Remove top cover and inspect
the membrane connection to
the control board. If work has
recently been performed on
unit, confirm pin to receptacle
alignment. Verify continuity
between appropriate pin
locations.
Faulty control board.
Consult with authorized CSZ
representative or replace
board.
The Hour Meter light is
activated.
Hour meter needs to be reset.
Check filter conditions and
replace if necessary. Reset hour
meter by holding "Fan Only"
and "High" while turning unit
on.