Dexon Canada Air Systems Inc
OWMDH Series Use Manual
Version 07.2019
Page 2
1.1 INTRODUCTION
Dexon blower heaters are CSA Certified and designed to meet the requirements of the Canadian
Electrical Code. The OWMDH series is suitable for outdoor wall mounted applications.
1.2 PURPOSE
To provide continuous positive pressure safety ventilation to pumping station wet wells, dry wells,
buildings, vaults and chambers for the safety of the operator and to provide a less corrosive
environment for equipment.
A function of the blower heater is to temper the ventilating air in order to mitigate the risk of freezing the
ventilated space. They will maintain a preset discharge temperature of b6
°
C to +18
°
C with an
adjustable 5
°
range. If the discharge temperature drops below 0
°
C (typically) the blower heater will shut
down to prevent the ventilated space from freezing.
This equipment is suitable for use in Class 1, Division 2, Gas Groups C and D, Temp Code T2C or for
Non-Hazardous Locations only.
FEATURES
Overheat Protection
Low Temperature Shut Down
Discharge Temperature Sensor
Adjustable Fan Speed in Auto
Mode
Full Fan Speed in Manual Mode
Auto Reset
Fan Boost Start
Proof of Fan Rotation
Staged Heating for Larger Units
CSA Certified
1. GENERAL COMMENTS
OPTIONS
Various Installation Configurations; outdoor
freestanding
– SMDH series, indoor inline
– IMDH Series, indoor wall mounted-
WMDH series and outdoor wall mounted
–
OWMDH series
Voltages from 120-600VAC, 1 or 3 phase
Class 1 Div. 2, Gas Groups C & D and
Ordinary Location Certified
External Alarm Interfacing
Manual Mode Interface for Hatch/Lid
Switch or PLC etc.
