2790

Common Causes

• Failed shower coolant pump motor
• Clogged pump suction filter or coolant lines overloading the motor
• Tripped or defective overload relay in the pump circuit
• Faulty ON confirmation (pressure/flow) switch or wiring

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = The shower coolant ON confirmation signal stayed off for over 3 seconds while the shower coolant motor was on
2. 2Read the code: code 1 means the shower coolant confirmation signal never arrived within 3 seconds of the motor starting - the pump is not delivering coolant.
3. 3Check coolant tank level and clean the pump suction filter and shower coolant lines; a clogged filter is the most common and cheapest cause.
4. 4Reset the pump motor overload relay and retry the shower coolant; immediate re-trip points to the motor.
5. 5Lock out power before opening the cabinet, then test the pump motor windings and check the overload relay condition and setting.
6. 6Confirm the ON confirmation (pressure/flow) switch actuates when the pump runs and its wiring is sound.
7. 7If the alarm returns after these checks, record the alarm number and code and contact Okuma service.