Thermolec ACU-STEAM, User Manual

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Page 23
CONTRACT
OR
17 Installing the Air Pressure Probe
17.1 The pressure probe (also called a Pitot tube) connected to the pressure differential switch inside the
unit checks whether there is enough air pressure in the warm air duct to activate the humidifi er.
17.2
The probe can be installed in either the warm air or cold air return duct, as close as possible to the
humidifi er, but before the steam diffuser. A 48” long plastic tube is supplied to connect the pressure probe to
the humidifi er.
Warning : Before installing anything on a duct, always check that you are not about to cut or drill into an air
conditioning coil or electrical accessories.
17.3 Drill a hole 3/8” dia. in an accessible location in the air duct.
17.4 Insert the probe and fasten it’s base to the duct using two sheet metal screws. The arrow visible on the
probe fl ange indicates the air fl ow direction in the duct (i.e. the curved end of the probe has to face the air fl ow)
Please see Fig. 17a and Fig. 17b.
17.5 Push one end of the plastic tube onto the probe outlet. Slip the other end of the tube onto the plastic
barbed connector at the end of the tubing already attached to the humidifi er for a warm air installation or
connect the plastic tube to the LOW barbed connector on the PD Switch located below the electronic control
board for a cold air return installation of the probe. Please see Fig. 17c.
AIR FLOW
Fig. 17a

Fig. 17b
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#KTHNQY
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#KTHNQY
Fig. 17c
This end is
connected
to PD Switch
HIGH (warm air)
LOW (cold air)