
DUALAIR® HEATING AND COOLING UNITS INSTALLATION OPERATION AND SERVICE MANUAL
SECTION 8: OPTIONAL HEATER CONFIGURATIONS 8.1 Distribution Duct
DualAir® units are designed to be connected to  | The duct must be designed as described on Page  | |
distribution and air inlet ducting.  | 14, Section 8.1 and Figure 10 to ensure that there is  | |
It is recommended that flexible duct connectors and/  | a homogenous air flow across the whole heat  | |
or attenuators are used to reduce duct born noises.  | exchanger. Failure to provide a properly distributed  | |
air flow will reduce the life of the heat exchanger.  | ||
It is recommended that the inlet ducting is arranged  | ||
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with both fresh air and recirculating air dampers to  | Contact   | |
take advantage of the "free cooling" stage provided.  | 
Distribution ducting must be insulated to prevent  | Department for recommendations regarding | ||||||
duct resistance and design. Tel: +44 (0) 121 506 | |||||||
heat gain during cooling mode.  | |||||||
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The air flow must be in the direction as stated for the  | 
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version being installed with the heater at the  | 
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discharge end.  | 
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Figure 10: Ducting | 
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NOTE: Duct size will be full size of inlet and outlet.  | 
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All joints between the heater and duct work should be  | 
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made as air tight as possible.  | 
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*Inlet Duct Minimum Dimension same as Outlet Duct  | 
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Twice  | 
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Minimum Dimension  | 
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Airflow Indicator  | 
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 Ducting
 Flexible Flange
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