HomeVision® Pro
© Corroventa Avfuktning AB
2021.02
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To help understand this principle here is an example that can be studied in parallel with the chart:
Setpoint, %RH:
65%
Hysteresis Upper/Lower:
+ 4%, -4%
Activation: Setpoint value + Hysteresis Upper = 65% +
4% = 69% Off: Setpoint value + Hysteresis Lower = 65% -
4% = 61%
Alarm, +RH:
10%
Added to the activation level to give alarm level.
Alarm level = Setpoint value + Hysteresis Upper + Alarm =
65% + 4% + 10 % = 79%
As seen in the example
, the setpoint value must not be mixed up with the highest permitted level
because the setpoint value exceeds the corresponding Hysteresis Upper before the dehumidifier is
activated. At high moisture load, relative humidity can increase slightly before the dehumidifier
makes an impact and the relative humidity in the crawl space begins to drop. The result of this is
that the setpoint value, if not entirely accurate, can be seen as an upper limit for the humidity's
average value over a longer period, and for this
there must be a margin, greater than the upper
hysteresis, for the humidity at which damage occurs.
The reason the user is given the option to influence hysteresis is that it must be possible to adjust
the system for optimum operating profile in any given location. Too narrow an interval, the range
given by the upper and lower hysteresis provides many starts and stops of the dehumidifier and
therefore an increase in equipment wear. Too great a range means that, at each activation, the
system drives down the humidity unnecessarily low resulting in increased energy consumption.
Mould index regulation
HomeVision® Pro permits, in addition to traditional, fixed, regulation of the relative humidity,
application of mould index regulation, MGI regulation. This regulation method uses the fact that the
mould growth, in addition to the humidity is also temperature dependent. At lower temperatures,
higher humidity can be tolerated without risking mould growth and the positive result of this is of
course the potential to save energy.
The regulation principle, as with the energy saving aim, implemented in HomeVision® Pro can be
clarified with the help of the chart below. The chart is not to scale but is intended only to clarify
the principle and actual parameters.
%-RH
Dehumidification on
Mould index curve
Alarm, +%RH
Safety margin
Dehumidification off
Temperature
RH-MGI
Hysteresis Lower
Hysteresis Upper
