A.O. Smith SGS - 100 Installation & Service Manual page 82

Code + Description Cause
Dirty or blocked fan
Because of a drop in
the supply voltage, the
fan is not running at the
correct speed.
The F02 entries below are applicable solely to appliances that have a 3-phase fan with frequency controller.
Fun supplying The live (phase) wires,
insufficient pressure between freq. controller
and fan are connected
wrong way around
Fan speed too low
Air pressure switch fails Air pressure switch
to close during pre- leads
purge.
Loose air pressure
switch hoses
Instruction manual SGS
Solution
1. Check if the fan is dirty
2. Check that the rotor can rotate freely
3. Reset appliance controller
1. Check the supply voltage, this must be 230 VAC (-15%, +10%).
2. Reset appliance controller
1. Check the wiring between the fan and the frequency controller
2. Rectify the assembly if it is incorrect
3. Reset appliance controller
1. Check the fan speed
2. If the fan speed is too low, check the settings
3. If the settings are correct, then replace the fan.
4. Modify the settings if incorrect
5. Reset appliance controller
1. Check the wiring between the air pressure switch and the
controller. Rectify any defect:
- if any wires are damaged, replace the wiring harness
- properly connect loose or detached hoses
2. Reset appliance controller
1. Check hoses between air pressure switch and burner/fan.
Rectify any defect:
- if any wires are damaged, replace the wiring harness
- properly connect loose or detached hoses
2. Reset appliance controller
Remark
See the SGS electrical diagram (17 "Appendices")
To replace the necessary parts, you must contact your installation
engineer
is
82