Desert Aire Aura QS, Installation And Operation Manual

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2.4 Auxiliary Heat Coil Piping
The Desert Aire dehumidifier may be equipped with an optional hot water or steam air heating
coil. This coil, when properly sized, will provide space heating during the winter months.
Use proper practice when designing and installing the coil piping to prevent poor coil
performance, shortened service life, or damage to the coil.
• The supply connections must not be supported by the coil headers.
• The control valve should be sized according to the pressure and flow rate
requirements, not by the coil connection size.
• On steam systems, use strainers, dirt pockets, and isolation valves to prevent clogging
the control valve and to simplify service.
• Install swing joints in the connection piping to prevent damage to the coil header from
thermal expansion.
• Use a backup wrench on the pipe stubs when attaching connections to prevent
damage to the header.
2.5 Water Piping Installation (for Q-Pump and Water Cooled Systems Only)
As an option, the dehumidifier may be equipped with a tower water or a heat pump loop
condenser. Use industry standard piping practices when connecting to such a dehumidifier.
Connections are copper stubs. Refer to submittal documentation for specific size per model.
Water Quality and General System Design
A 60 mesh or finer strainer must be installed in the water inlet line. Flush fieldinstalled piping
thoroughly before you put the dehumidifier into service. A piping system not properly flushed or
filtered will cause the brazed-plate heat exchanger to lose efficiency or fail prematurely due to
clogging and/or fouling.
To prevent premature failure of the heat exchanger, maintain the water at a pH of 7.4, but
never below 6.0. Do not use water with high concentration of sulfur, chlorine, or sodium
chloride.
A dedicated circulating pump must be used unless the main pump can develop enough head
to overcome the combined resistance of the water condenser and the piping connected to it.
See specific Flow Rate section for the required water flow rate and head for your application.
Desert Aire - QS/QV Manual