Robertshaw 9400 - Manual (Page 10)

Step 5: Troubleshooting
Symptom Remedy
Thermostat does not turn on system. Check wiring (see Installation
section).
If problems with thermostat cannot be resolved, call:
Technical Support: (800) 445-8299
Monday-Friday 7:30 AM - 5:30 PM CST
10
Thermostat turns system on and
off too frequently. Increase temperature differential
(see Changing the Temperature
Differential section).
Display is blank, flashing or
constant LOW BATT. Replace batteries.
System fan does not operate
properly. Move fan option switch to either
gas or electric, to match system
(see Installation section).
Thermostat does not display
proper room temperature. Check F/C (Fahrenheit/Celsius)
setting. See Changing Fahrenheit
(F) to Celsius (C).