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FIGURE 12. HUMIDISTAT BOARD & SENSOR
12.10 SETTING SPEED POSITIONS 1 & 2
12.10.1 Ensure unit is out of installer mode and switch live is OFF.
12.10.2 After setting the required airflows in auto mode turn the switch to position
1.
12.10.3 Rotate the potentiometer 1 (RV1 on reverse side of the switch) to the
required position to provide the required airflow.
12.10.4 Turn switch to position 2.
12.10.5 Rotate the potentiometer 2 (RV2 on the reverse side of the switch) to the
required position to provide the required airflow.
NOTE:
In manual modes 1 & 2, if the switch live is turned ON, both fans turn to
the setting which was set in the auto mode.
12.11 BYPASS POSITION 3
12.11.1
In warm weather, in order to reduce the effectiveness of the heat
recovery switch to bypass mode, the JS9 switch setting BYPASS reduces
the supply fan to the minimum set commissioning speed. The extract fan
increases to maximum set boost speed.
12.12 BOOST ON DELAY
To set boost on delay for 2 minutes, set dip switch 3 to off.
12.13 OVERRUN
Boost overrun time can be set by linking JP1 with link provided. The time can then be adjusted
using RV1 (0 - 30 minutes).
12.14 HUMIDISTAT (OPTIONAL)
12.14.1 The Humidistat control boosts the airflow of the unit. It is triggered by a sensor located
within the MVHR System.
12.14.2 It is factory set for a nominal 70% RH.
12.14.3 The Humidistat is adjustable and can be carried out by rotating the potentiometer on the
control board.
12.14.4 Turn anti-clockwise to lower the set point and
clockwise to increase the set point.
SENSOR
HUMIDISTAT
CONTROL