White Rodgers 921 Thermostat User Manual


 
TROUBLESHOOTING
A
B
C
7
The self diagnostic test
found a problem with the
gas valve driver circuit
1. Cycle power to the water heater off for 10 seconds
and then back on.
2. If the above step did not cleat the error, the INTEL-
LI-VENT™ control must be replaced
A
B
C
8
The self diagnostic test has
detected a problem with
the internal microcomputer.
1. Cycle the external power off for 10 seconds and
then back on.
2. If the above step does not clear the error, the
INTELLI-VENT™ control must be replaced.
A
B
C
9
The self diagnostic test has
detected a problem with
the internal circuit
1. Cycle the external power off for 10 seconds and
then back on.
2. If the above step does not clear the error, the
INTELLI-VENT™ control must be replaced.
A
B
C
10
Flame signal sensed out of
proper sequence.
1. Replace the INTELLI-VENT™ control.
A
B
C
11
The high temperature ther-
mal cutoff is open
1. Replace the INTELLI-VENT™ control.
A
B
C
12
The diagnostic test has de-
tected one of the tempera-
ture adjust buttons stuck
closed
1. Make sure that there are no objects leaning against
the front of the control.
2. Lightly press and release each of the buttons once.
3. If the above actions do not clear the error, the
control will continue to regulate water temperature
at the last setting, but you not be able to change
settings unless you replace the INTELLI-VENT™
control.
A
B
C
13
The self diagnostic test
has detected that the water
temperature sensor is ei-
ther open or short circuited.
1. Check that all wiring is correct and that there are no
open or shorted circuits.
2. If no wiring problems are found the INTELLI-
VENT™ control must be replaced by a qualified
service person.
A
B
C
14
The self diagnostic test
found a problem with the
Flammable Vapor Sensor
1. Check that all wiring is correct and that there are no
open or shorted circuits.
2. If no wiring problems are found the flammable
Vapor Sensor must be replaced.
A
B
C
15
The control detected the
presence of flammable
vapors near the appliance
and entered lockout.
1. If you smell gas, STOP! Follow the instructions,
“What to do if you smell gas” on page 1 of this
instruction sheet. Otherwise call a qualified service
person for replacement of the control.