Sterilization Program Phases - W&H Lexa MN-111 Instructions For Use Manual

Sterilization program phases

LEGEND OF THE STERILIZATION PROGRAM PHASES
Following is the description of the sterilization phases.
Code Phase
PHE Pre-heating
phase
HEA1 Heating
phase (steam
HEA2
pressure
pulses)
HEA3 Pressure rise
STLZ Sterilization
phase
DRY Exhausting
drying phase
LEV
Levelling
phase
Lexa | Instructions for Use | MN-111 ENG Rev14 | 03/04/2023 | © W&H Sterilization Srl
Description
Pre-heating of the sterilizer steam generator and chamber. This phase is not considered a part of the cycle.
Initial heating phase to remove the air from the sterilization chamber. Air is removed using pressure pulses followed by discharge phases. The
iteration of these phases reduce the percentage of air inside the chamber and determinates the correct sterilization conditions.
Heating phase to achieve the sterilization conditions (pressure and temperature) for the selected cycle.
Sterilization condition (pressure and temperature) maintained for the time specified for the selected cycle. During this phase the unit controls
the theoretical temperature (pressure converted in temperature, because of physical behaviour of water) and the steam temperature inside the
chamber. The value must be between the sterilization temperature band, and the difference between them must be lower than 3.6 °F (2 °C). If
the temperature drops below the sterilization temperature band a restart process procedure is automatically executed by the sterilizer
(according to ST55). The sterilizer controls the sterilization condition through steam generation. The steam generation is controlled by a PID, that
modulates the electrical power using as feedback the instant average between theoretical and internal temperature.
The objective of this phase is to dry the load placed in the sterilizer chamber. The drying phase is divided in two step:
The first step is the depressurization phase, when most of the steam is removed from the chamber. The second step is the drying of the
n
load.
Duration of the DRY phase depends on the selected profile.
n
Pressure inside the sterilization chamber is leveled to the atmospheric pressure.
Technical data
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