Honeywell 700 User Manual

17

66-2069—02

If the viewing head produces any pulses during the last one 

third of the self-check time, the relay will immediately de-

energize, the display will show “LO” (lockout), and the FAULT 

LED will flash on and off rapidly. Exit lockout by pressing 

RESET. 

If a pulse or pulses come in during the last one third of the 

self-check time while the automatic data sampling is taking 

place, the automatic process will be aborted, the relay will be 

de-energized if it was energized, the display will show “LO” 

(lockout), and the FAULT LED will flash on and off rapidly. 

Press RESET to exit this. 

If a viewing head is disconnected, the display will show “L1.” 

Reconnect the viewing head and press RESET.

If the signal processor displays “EE” upon power up, it is an 

indication that the EEPROM stored data for the viewing head 

does not match for the currently connected viewing head. For 

further information on this condition, refer to the Parameter 

Match Error Section below.

If the signal processor displays “EE” upon power up, it is an 

indication that the EEPROM stored data for the viewing head 

does not match for the currently connected viewing head. This 

error can occur when a different model viewing head is 

connected to the signal processor than was previously 

connected. As a result, the signal processor discards the 

previous stored parameters and loads factory defaults, except 

the RELAY ON SETPOINT is set to 31.

Setpoint values and other parameters plus error-checking 

codes are stored in EEPROM (Electrically Erasable 

Programmable Read Only Memory) in the signal processors. 

This data is then error-checked when it is read at power up. If 

the data does not match exactly what was previously stored, 

the signal processor discards all data, displays “EE”, and 

loads factory defaults. The RELAY ON SETPOINT is set to 31. 

Since the flame count cannot go this high, the flame relay 

cannot be energized. The signal processor can be reset by 

changing the RELAY ON SETPOINT to a reasonable value or 

by pressing LOAD FACTORY DEFAULTS.

The signal processor requires continuous communication with 

the connected viewing head. If the viewing head is 

disconnected, communication will be lost and the display is 

made inoperative where no settings can be examined or 

changed. To correct this condition, reconnect the viewing 

head to the signal processor and cycle power.

See “Grounding and Shielding” on page 3 for further 

troubleshooting help in regards to proper grounding and 

shielding techniques.

The UV sensor has a limited lifespan. Under extreme 

conditions, the lifespan can be as low as 10,000 hours. 

However in the most favorable conditions, the lifespan is 

50,000 hours or more. The service life of the UV sensor is 

considered terminated when the sensitivity becomes lower 

than 50% of the initial value.

A monthly sensitivity check is suggested to determine if the 

UV sensor’s life is terminated. The reading of the signal 

processor digital display should be compared to the initial 

reading of the unit when it was installed. Ensure similar burner

fire conditions of the application, and that the same gain 

settings of the viewing head, are used during each sensitivity 

check. If it is determined that the sensitivity is below 50% of 

the initial value (terminated life of the sensor), the sensor 

should be replaced.