Enviro HL SERIES User Manual

ENVIRO-TEC
22
FORM ET115.24-NOM11 (118)
DIFFERENTIAL AIR PRESSURE SWITCH
General information
This accessory is a dierential pressure switch with
a normally-open (NO) dry contact that is factory
calibrated to close at a dierential pressure of 0.15
inches of water or greater. The switch measures the
pressure dierential between the unit’s fan section and
the environmental pressure outside the unit. When the
lter is suciently clogged or dirty, dierential pressure
will rise and the switch will close.
Technical specications
Electrical
Initial resistance <500mW
Rating
3.15ma @ 125VAC
10-20ma @ 5-24VDC
Adjustable set point ranges in H
2
O
Ranges
In H
2
O
Min. Max. Proof
0.10 0.50 5.0
Functional
Operating positing
Diaphragm vertical, barbed
ttings horizontal
Operating temp.
-40 °F to 140 °F
(-40 °C to 60 °C)
General measurements: Pressure Switch
Figure 11
Installation
Assembly
The dierential air pressure switch is mounted inside
the unit with double sided tape behind the lter retention
tab. (See gure 12a). Instructions for commissioning or
replacing the dierential air pressure switch:
a. Disconnect main power on the unit.
b. Secure dierential air pressure switch on the lter
retention tab using double sided tape. Position
the pressure port (marked with “+”) outside the
chassis exposed to the environment. The vacuum
port should extend inside the chassis and be open
to the unit’s fan section. (See gure 12b.)
c. Wire the NO relay using .187 quick connectors.
d. Verify all connections before reconnecting main
power.
Figure 12a
Figure 12b

Enviro HL SERIES Specifications

General

Brand	Enviro
Model	HL SERIES
Category	Fan
Language	English