Combat HVAC ELU 100, Installation And Commissioning Manual, Page: 21 / 52

Unit Heater Installation, Commissioning, Operation and Service Manual
15 16
Combat Elite Unit Heater EL231117 Orig
Ducting
Dimension
“X”
Minimum-
Twice
Dimension
“X”
Minimum-
Twice
Dimension
“X”
Airflow Indicator
Flexible Flange
Ducting
Optional Heater Configurations
SECTION 9
9.1 Distribution Duct Work for ELUB, ELUC, ELUD Heaters
ELUC heaters have the fans enclosed so that the heater may be
connected to inlet ducting.
ELUD heaters are supplied with inlet and outlet duct spigots for mounting
the heater into a customer designed duct system for use with an external
fan system. It is a recommended that flexible duct connectors are used to
reduce duct born noises.
When installing ELUD heaters onto ducting force the fan to run.
Do not rely on the fan thermostat to turn it on.
Any such device must be in parallel with the fan thermostat so that the
fan run-on operation will still operate.
9.1.1 ELUD Heaters
For ELUD heaters, it is essential that the airflow in the duct system is at
least that specified in the Data Sheet on Page 8, Section 5.2 and in the
correct direction across the heat exchanger as indicated by the arrow
on the heater. Higher airflows are permitted, but will cause a lower exit
air temperature. It is recommended that the fan is positioned to blow
the air through the heat exchanger.
The duct must be designed as described on Page 16, Section 9.1 and
Figure 10 to ensure that there is a homogenous air flow across the
whole of the heat exchanger.
Failure to provide suitable air flow properly distributed across the heat
exchanger will reduce the lifespan of the heat exchanger.
The fan motor, or its control must contain a method of overload
protection. When installed remote from the heater, the fan must be
supplied via a local electrical isolator positioned and properly labelled
to prevent inadvertent operation.
Figure 10: Ducting