Aiko CTH3-200 Manuale Utente

Pagina di 82
CTH3-S
ERIES
 I
NSTALLATION
, O
PERATION
 
AND
 S
ERVICE
 M
ANUAL
60 of 71
12.1 Control LED
The control inside the heater's control compartment 
is equipped with a tri-color LED. The LED offers 
comprehensive diagnostic capability. The LED is 
showing some form of status signal at all times when 
the control is powered. The color of the LED 
differentiates normal from error conditions as follows:
GREEN indicates normal operation. 
RED indicates an error condition.
YELLOW (fast flashing) indicates a RETRY attempt.
LED NOT LIT indicates no power to control.
12.2 General LED Codes
No LED: 
No Power to control.
Slow Green: 
LED slowly flashes on and off, 
indicates power to the control 
board but no call for heat.
GREEN, 1 flash:
Call for heat indicates the 
heater is performing the safe 
start pre-purge function or 
H.S.I. warm-up.
GREEN, 2 flashes: 
Call for heat indicates the 
heater is performing light off, 
heater warm-up, or heater run.
GREEN, 3 flashes:
*Only applicable for 
thermostat control*
Gas ON - No call for heat, unit 
modulating from single stage 
thermostat. 
AMBER, 1 flash:
Call for heat when flame signal 
is below 1µA
AMBER, 2 flashes:
Gas ON - Call for heat when 
flame signal is below 1µA
AMBER, 3 flashes:
*Only applicable for 
thermostat control*
Gas ON - No call for heat, unit 
modulating from single stage 
thermostat when flame signal 
is below 1µA.
AMBER,
Fast Flashing:
Heater is in RETRY mode.
RED Steady LED: 
Control FAILURE,
No 24 V power supply. 
RED, 1 flash: 
Lockout- Insufficient sensed 
air pressure when blower is 
on.
Condition could be caused by:
• Air Side Door
• Blower
• Obstruction in 
   inlet or outlet
• Pressure hose fittings
• Pressure Switch
RED, 2 flashes: 
Lockout- Blower air pressure 
reads above zero level when 
blower is off. 
Condition is caused by 
a pressure sensor failure or 
complete blockage of air 
intake or exhaust vent.
RED, 3 flashes:
Lockout- Flame is sensed on 
when it should be off or off 
when it should be on. 
Could be caused by:
• Flame Rod
• H.S.I.
• Gas Supply
• 120 V Supply Polarity
• Board Fault
RED, 4 flashes:
Lockout- Gas Valve. 
Condition caused by main 
valve on gas valve. 
Check gas valve wiring.
RED, 5 flashes:
Lockout- Board Failure. 
Board must be replaced.
     
RED, 6 flashes: 
Not used.
RED, 7 flashes:
Lockout- Fuse Open.
Condition could be caused by:
• Fuse blown
• High Limit Switch open a
board location J3