Specifications

CAREL gaSteam
25
8.2 Autotest
When the humidifier is started, the controller initiates an Autotest procedure to ensure that the humidifier can
fill, drain, and monitor water levels properly. This test may take up to 30 minutes to complete depending on the
amount of water in the unit when it is turned on. The Autotest will be signified by a flashing 'At' code on the
display (see Figure 8.2.1). Note: The unit performs this test only when first turned on, not each time a call for
humidity is received by the controller.
Figure 8.2.1
If the Autotest fails, the appropriate error message will be displayed and the humidifier will pause in operation
until it is reset by pressing PRG or manually turned off.
The Autotest consists of the following sequence of events:
a) The tank is either drained or filled to the low level sensor;
b) The tank is then filled to the maximum water level sensor. These first two steps ensure that:
- The low, intermediary, and high water level sensors are working;
- The fill valve is working properly;
- The unit is able to fill quickly enough with water for effective operation/control
c) The tank is then drained to the low level sensor. Successful completion of this step ensures that:
- The drain pump is working properly;
- The drain filter is not clogged or the drain line otherwise obstructed
Once the Autotest has successfully been completed the 'At' message will disappear and the unit will begin
normal operation. It will fill to the intermediary level and begin producing a quantity of steam at a rate
determined by the controller, depending on the set point and the readings of the probes.
8.3 Bypassing the Autotest
In the first 5 seconds from the start-up of the machine the water/electrical Autotest can be bypassed (the next
time the machine is started, the Autotest phase will be performed). To bypass the Autotest phase, within 5
seconds from starting the machine, press the SEL button and hold for at least 2 seconds. The “-nt” message
will appear (see Figure 8.3.1) to visually confirm that the water/electrical Autotest will not be performed and that
the machine will immediately start the steam production phase.
Figure 8.3.1