ESAB 100i Service Manual page 102

iSERIES 100 /200 /300 /400
system that has been run before it normally takes only a few seconds to establish proper flow. In any case the
pump will run for 4 minutes before setting the 404 fault.
First determine if the pump motor is running and if so is there any coolant flowing. With the right lower side
panel removed touch the pump and feel for vibration to indicate if the motor is running. Observe the clear
coolant hoses to see if they are full of coolant. There are two hose fittings on the back of the tank. The upper
one is the coolant return. Remove the tank filler cover. You should see a fairly strong stream of coolant from
that fitting. The lower fitting is from the pump bypass valve. If the pump is operating some coolant may be
exiting that fitting as well. If these fittings are below the coolant level you may have to drain out some of the
coolant to see this. If a strong stream is exiting the bypass (lower) fitting but nothing from the upper fitting,
you probably have some kind of blockage.
Reasons for 404 faults (Coolant not flowing):
• In new installation, coolant has not circulated all the way through the leads. Add more coolant if neces-
sary and recycle the power to restart the pump and 4 minute timer.
• Coolant supply & return leads are reversed, check valve in torch coolant return prevents reverse flow.
• Torch parts removed or are wrong style so torch check valve shuts off flow.
• Torch coolant tube damaged or the tube extension (if required) missing.
• No power to pump motor.
• Pump/motor failure.
• Bypass valve defective or adjusted incorrectly.
Damaged Coolant Tube
Coolant tube includes a check valve at its upper end. When cartridge with consumables is not installed the
spring loaded coolant tube is fully extended closing the check valve preventing coolant from leaking out.
When consumables are in place they push the tube inward, opening the check valve, allowing coolant to flow.
The coolant tube has fingers on the end to contact the inside of the electrode and allow coolant to flow through
the openings between the fingers.
The fingers can be bent over or broken if reasonable care is not taken when the cartridge is not in place. If the
fingers are bent or broken it shortens the tube so the consumables may not push the tube in enough to open
the check valve resulting in no coolant flow. The coolant tube assembly may be replaced separately from the
torch head.
Some consumables use an extension on the coolant tube. A missing extension will not allow the check valve
to open.
No Power to the Pump Motor
The pump motor is powered by 230 VAC controlled by the MC3 control relay. During the 4 minutes after turning
on power, before the 404 fault code is displayed, measure for 230 VAC at the motor connector J16 pin 1 to pin 3.
A-82
Internal Check Valve
Fingers
APPENDIX
Coolant Tube Extension
Art # 12312
Manual 0560956456