AERCO KC Series Equipped with C-More version 3.04 - Manual (Page 75)

TROUBLESHOOTING
7-8
KC1000 WATER HEATER TROUBLESHOOTING TABLE – Continued
FAULT INDICATION PROBABLE CAUSES CORRECTIVE ACTION
PRG SWTCH CLOSED
DURING IGNITION
(continued)
3. Switch wired
incorrectly.
4. Defective Power Supply
Board or fuse
5. Defective IGST Board
3. If the switch is wired correctly, replace the switch.
4. Check DS1 & DS2 LEDs on Power Supply Board. If
they are not steady ON, replace Power Supply Board.
5. Check “Heartbeat” LED DS1 and verify it is blinking
ON & OFF every second. If not, replace IGST Board.
PRG SWTCH OPEN
DURING PURGE
1. Defective purge switch.
2. No voltage present at
switch.
3. Switch wired
incorrectly.
4. Defective Power Supply
Board or fuse
5. Defective IGST Board
1. If the air-fuel valve does rotate, check the purge
switch for continuity when closing. Replace switch if
continuity does not exist.
2. Measure for 24 VAC from each side of the switch to
ground. If 24VAC is not present, refer fault to qualified
service personnel.
3. Check to ensure that the switch is wired correctly
(correct wire numbers on the normally open
terminals).
4. Check DS1 & DS2 LEDs on Power Supply Board. If
they are not steady ON, replace Power Supply Board.
5. Check “Heartbeat” LED DS1 and verify it is blinking
ON & OFF every second. If not, replace IGST Board.
REMOTE SETPT
SIGNAL FAULT
1. Remote setpoint signal
not present:
Not yet installed.
Wrong polarity.
Signal defective at
source.
Broken or loose wiring.
2. Signal is not isolated
(floating) if 4 to 20 mA.
3. Control Box signal type
selection switches not
set for correct signal
type (voltage or
current).
1. Check I/O Box to ensure signal is hooked up.
Hook up if not installed.
If installed, check polarity.
Measure signal level.
Check continuity of wiring between source and boiler.
2. Check signal at source to ensure it is isolated.
3. Check DIP switch on PMC board to ensure it is set
correctly for the type of signal being sent. Check
control signal type set in Configuration Menu.
RESIDUAL
FLAME
1. SSOV not fully closed.
2. Defective Flame
Detector.
1. Check open/close indicator window of Safety Shut-Off
Valve (SSOV) and ensure that the SSOV is fully
closed. If not fully closed, replace the valve and or
actuator.
Close gas shut-off valve downstream of SSOV. Install
a manometer or gauge in a gas test port between the
SSOV and the gas shut off valve. If a gas pressure
reading is observed replace the SSOV valve and or
actuator.
2. Replace Flame Detector.