fisair HEF2 SERIES, Installation And Maintenance Manual

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HEF2 Series MANUAL
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16.2. Stages control
❖
The Relative Humidity probe (SHR) must be placed in the room or in the return. The PI or PID
regulation loop turns the solenoid valves of each stage (EE) on or off.
❖
The pump will start whenever moisture is required.
❖
The Temperature probe (ST) is located in the drive and controls the Pre-heating coil (BC) via the
PID loop. This BC must have 10-20% extra capacity as a safety factor.
❖
This type of control will have an accuracy of about ± 5% RH. The use of evaporative cassettes
is 50% less than in on/off systems.
❖
Care must be taken with the accuracy of the probes used.
BC
BC: Pre-heating coil
ST: Temperature sensor
SHR: Relative Humidity Sensor
EE: Stage solenoid valve
HEF2E
EE
ST
SH
R