20 69-0432—1
Voltage at Clock Terminals
AC VOLTAGE AT
C-R TERMINALS POSSIBLE CAUSE
CHECK ACTION
0 Vac 1. System power is Off. 1. Restore power.
2. Short in clock power supply wiring. 2. Replace wiring.
3. Limit switch contacts stuck open. 3. Free or replace limit switch.
4. Transformer supplying power is
burned out. 4. Replace transformer.
Up to 15 Vac. 1. System transformer used to power
the clock is inadequate. 1. Use additional (separate)
transformer.
2. Additional (separate) transformer
used to power the clock has
inadequate voltage.
2. Install transformer with proper
secondary voltage.
15 to 30 Vac. 1. Spring fingers on thermostat are
not making proper contact with the
subbase terminals.
1. Rebend spring fingers to a 45
degree angle to assure proper
contact.
2. Clock has failed. 2. Replace the thermostat.