Operating instructions

FAULT DETECTION

Faul t detection i s pe rformed at

all times, except in Off mode.

IMPORTANT:

The boiling temperature of

water will vary with altitude.

See chart, page 11.

Fault Detection:

Software-level fault detection is performed using the temperature

probe, and the water level sensor.

In the event of a fault, solenoid valves are closed, the heater

triac is turned off, all LEDs flash, an error message is displayed

and the system halts by entering Error Mode.

The system can be reset by removing the power to the system or

by holding down the 8th (Left Stop Brew key) for 2 seconds.

These errors are monitored at all times:

1. Probe/Heater Error

If the temperature of the water does not increase 4ºF in 4

minutes with the heater on, then either there is a probe and/

or heating element failure, or the water is boiling. In either

case, the system halts with a "probe/heater err" message.

2. Maximum Temperature Reached

If the temperature exceeds a limit, then an overheat error

message is produced. This error can occur if the heater triac

fails "on". The maximum temperature should be set in the

menu system as to prevent boiling.

3. Water Level Sensor Timeout

If the inflow valve is opened and water is not detected within

30 minutes, the message no water sensed is produced.

This can be caused by level sensor failure or water inflow

valve failure. After the tank is filled to full capacity, the time

limit varies with the state of the outflow valves:

a. Two sides brewing: 5 minutes

b. One side brewing: 3 minutes

c. No brewing being performed: 1 minute

4. Internal Component Fault

The controller is also capable of verifying the proper

functioning of internal components:

a. "Keypad locked" message indicates that a key has been

held down for an extended amount of time. This is

perceived as a fault in the keypad controller.

b. "Valve fault" message indicates that the valves are not

responding properly.

675 p/ n 74346 SS-2 Programming Manual