Unit Configurations

Bebco produces Model WDP Wall Mount and RDP Remote Mount Whisper Drive™ Units to provide a wide range of building pressurization solutions that are UL Classified to meet all requirements for Class I, Division 1 and 2, Group C and D Hazardous Locations.

Model WDP Whisper Drive™ Units mount through a framed cutout in the exterior wall of the room or building to be pressurized. They feature primary and secondary fans, along with pre-wired controls, to simplify installation, and only requires wiring to a power source, an alarm system and optional remote-control switches to become fully operational.

Model RDP Whisper Drive™ Units may be mounted on an exterior wall or roof and feature primary and secondary fans, along with pre-wired disconnect switches. A Remote-Control Station ships separately, for interior or exterior wall mounting. Installation requires atmosphere or room pressure reference tubing, and motor power wiring between the RDP Housing and Remote-Control Station enclosure, for wiring to a power source, an alarm system and optional remote-control switches.

As further detailed below, these configurations provide a complete but versatile stand-alone solution for pressurization. Please contact a Bebco Sales Associate if you have any questions regarding which configuration may be best suited for your particular application.

Wall Mount Dual Fan Building Pressurization Units

Bebco Model WDP Units feature a seal-welded housing that features two fan assemblies, one pressure gauge, one electronic control system, a screw fastened control enclosure cover, a full-size rear door, a high memory replaceable gasket, pinned hinges and hex Allen wrench latches, a discharge grille with washable filter and three intake air stack ports with covers, one each on the sides and top of the unit.

The housing must be installed in the vertical position as shown, and includes one seal-welded interior trim bezel that is attached by screws into pre-drilled and tapped holes in the housing. Four miter-cut angle flange brackets are provided for the exterior side of the housing. They are secured by drilling and tapping holes in the housing and wall surface, which may range up to eight (8) inches thick.

Installation is completed by routing conduit or rated cabling from a power source, alarm system and optional remote control switches to junction box hubs at the bottom outer corners of the housing.

WDP Units are available in the following Model sizes and ratings:

WDP-12: 21 Square Feet Openings, Maximum
WDP-16: 31 Square Feet Openings, Maximum
WDP-20: 55 Square Feet Openings, Maximum
WDP-24: 75 Square Feet Openings, Maximum

The quality and durability of Bebco Model WDP and RDP seal-welded housings provides a distinct advantage that ensures years of extremely quiet maintenance-free operation. The left image shows the interior trim bezel, along with the room pressure indicator and one of three intake air stack ports, located on both sides and top of the housing. This image also shows the control operators and indicators, the screw fastened controls cover plate and the discharge filter grille.

The right image shows the full size rear door and the primary and secondary motors, along with two junction boxes. These boxes are prewired to the controls and fitted with conduit hubs that extend through the bottom of the housing for field wiring. The left junction box is optional, and contains standard or intrinsically safe signal input terminals that can be wired to emergency control override and emergency shutdown actuation switches. The right junction box is a standard feature of all Model WDP Whisper Drive™ Unit Housings, and contains alarm signal output and unit power input terminals.

IMPORTANT NOTES:
Model ratings above and below represent the maximum permissible area of all “openings capable of being opened”, in accordance with NFPA Code 496.

Typically, most pressurized buildings and rooms only feature doors, but operable windows and other similar items must also be considered with exception only to equipment access doors that are properly labeled and sealed during normal operations. In addition, the integrity of all doorway gaskets and other factors of building construction may affect the unit’s performance. Please ask a Bebco Sales Associate for more information regarding these critical aspects that affect proper unit size selection.

Remote Mount Dual Fan Building Pressurization Units

Bebco Model RDP Units feature a seal-welded housing that features two fan assemblies pre-wired to two separate disconnect switches, a full-size door with a one-piece high memory replaceable gasket, pinned hinges and hex Allen wrench operated latches, a flanged discharge opening, and three intake air stack ports with covers, one each on the opposite end and sides of the unit.

The housing may be installed in any position and is furnished with four vibration isolators. The isolators are provided to mount the housing in a preferred location by drilling through bolt or tapped holes as required to secure the unit firmly to a remote frame, exterior wall or roof surface. Ducting is then required to connect the Unit’s discharge to an HVAC Unit make-up air inlet or directly to the room or building to be pressurized.

The Remote-Control Station mounts on any interior or exterior wall and requires conduit or rated cabling routed from the disconnect switches, a power source, an alarm system and optional remote-control switches. Installation is completed with a tube connecting the room pressure indicator to atmosphere or room pressure.

RDP Units are available in the following Model sizes and ratings:

RDP-12: 21 Square Feet Openings, Maximum
RDP-16: 31 Square Feet Openings, Maximum
RDP-20: 55 Square Feet Openings, Maximum
RDP-24: 75 Square Feet Openings, Maximum

Bebco Whisper Drive™ Model RDP Remote Mount Building Pressurization Units may be mounted in any orientation to an external wall surface or roof of your pressurized room or building to conserve interior wall space. As shown in this image, Model RDP Units feature a highly durable seal welded housing and inline primary and secondary fan assemblies.

The Unit also features two pre-wired explosion proof fan motor disconnects and three intake air stack ports, located on the top sides and end of the housing in this image that direct air through the housing to a flanged discharge opening on the bottom end. The Remote-Control Station is shipped separately as shown, for interior or exterior wall mounting. Installation requires routing a tube to reference atmosphere or room pressure, wiring the disconnect switches to the Remote-Control Station enclosure and wiring the controls to a power source, an alarm system and optional remote-control switches.