Ventilated rodent racks require a constant supply of fresh, HEPA filtered air (and in many cases, consistent exhaust flow) to be delivered to each individual rack. This can be accomplished with rack mounted blowers such as our smart blowers, or by using an in-house ventilation system.

However, in-house systems are difficult to monitor at the point of use (the individual rack), and the flows can be quite irregular. Allentown has designed new products to help regulate and monitor the airflow to each rack, to maintain the integrity of every cage.

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Variable Flow Valve A proprietary and patent-pending solution which supports multiple room level airflow control applications while eliminating the costs and time of rebalancing rack connections and room air: An airflow regulator for positive/negative control A fixed bypass for equalizing different size racks An adjustable exhaust thimble to house HVAC

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Cage Rack Valves

Constant volume devices which automatically adjust in reaction to fluctuations in supply and exhaust air streams.Mounted directly in line with the ductwork, the cage rack valves contain a spring loaded cone that slides in and out of a narrow throat, in response to air pushing against the wide end of the cone, restricting the open area for air passage when necessary. The response of this cone is precision tuned so that the output of the valve is constant within 10% of its set point. When equipment is added or removed from a duct system, air balance to a room is changed by opening a door, loaded filters, or any other disturbance, the valve insures that the ventilated rack will continue to receive it's specified airflow.

• Small, lightweight package (19"/483mm)
• Reacts to disturbances in less than 1 second
• Field adjustable
• Capacity: 30-230 CFM/51-390 CMH
• Requires Duct pressure 0.5" WC to 3.0" WC/125 Pa to 750 Pa

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Thimble Ceiling mounted 6" to 4"/152mm to 102mm round thimble connection Flush mounted or Iris damper mounted versions Stainless steel construction - 11 gauge Provides direct connection to exhaust system with use of exhaust blowers Assists in cage level heat and odor removal Flow Range: 225 CFM/383 CMH max Custome thimbles available

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Rack Simulator

Allentown's patented Rack Simulators simulate the load of a IVC rack on the HVAC system. When hose connections are removed from the rack (to move the rack for cleaning, etc.) the spring loaded simulators automatically close, restricting the airflow in and out of the system to a level equivalent to a complete ventilated rack. This prevents a system imbalance, which would adversely affect the airflow to and from the remaining racks connected to that same system.

• Color coded (red=exhaust, blue=supply) for correct connection of rack
• Spring actuated for fail safe activation upon removal from rack
• Permanently affixed to ceiling mount flex hose
• Lightweight, durable, molded Noryl plastic
• Fits 3" or 4"/76mm or 102mm diameter hose

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Iris Damper Iris Dampers are ideal for adjusting individual drops to achieve airflow balance with in-house supply or exhaust. The iris-style adjustable orifice allows airflow adjustment without introducing turbulence or uneven airflows typical or blade dampers. The infinitely adjustable Iris Damper requires a special tool, eliminating accidental or unauthorized manipulation Fits standard 4"/102mm drops Stainless steel assembly with galvanized or stainless iris damper

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FID 4

Flo Indicating Damper installs directly to the ceiling connection to the house HVAC system, and provides a gauge for visual indication of sufficient airflow. The integral iris damper is adjustable to tune the flow of air to an appropriate level for each ventilated rack. The Flo Indicating Damper can also be used to simulate a rack load, by further closing the damper when a rack is removed from the system.

• Measures differential pressure on both sides of iris damper to indicate restriction of air flow and setting of damper
• Angled gauge position for easy viewing of ceiling mounted station
• Built-in, adjustable iris damper
• Simple, pass/fail color-coded gauge
• Stainless Steel construction