20
21 69-0639—1
Troubleshooting (Continued)
Troubleshooting (Continued)
Problem Check Action
Thermostat setting —calibration of thermometer. See instructions on page 24.
and thermometer
reading disagree.
(continued).
Clock does not run. —voltage across the two Remove thermostat from the wallplate
C terminals. or subbase and measure the voltage.
Refer to the table on page 22 for cause
and reaction.
— pins in program dial. If pins are Push down on pins to make sure they
not completely seated in are completely seated in program dial.
program dial, jamming with
index wheel may occur.
Clock loses time. — power. May be interrupted. Make sure power is on. Reset clock.
(Continued)
Problem Check Action
Clock loses time. —high limit control. If clock- Wire separate transformer to power
(continued). powered through system trans- clock, or install backup batteries as
former, power to clock and shown on page 9.
equipment may be off for safety.
—filter. May be clogged. Safety Replace filter and reset clock.
limit on equipment may cut off
power to system.
—backup batteries may need Replace with two new AAA alkaline
replacement. batteries. See page 9.
1Not applicable on model used in heating-only system.
2Not applicable on model used in cooling-only system.
If this Troubleshooting section has not solved the problem, call a qualified service technician or
Honeywell Assistance Center, 1-800-468-1502, Monday-Friday, 7:00 a.m. to 5:30 p.m., Central time,
for additional assistance.