'D' Range Modular Air Handling Units

Capacity

D range air handling units are available as standard in twenty two different sizes covering capacities from 0.52m³/sec to 54.22m³/sec.
Units are adaptable for all ventilation and air conditioning applications. They are of modular construction and suitable for internal or external mounting.

Selection

Selection is generally dependent on coil velocities. Duties are listed for typical heating and cooling coil velocities of 2.0m/s, 2.5m/s and 3.6m/s.

Arrangements

The smaller units in the range, up to D80,can be supplied as single packaged units, where all components are housed in one frame, details are given in the SP brochure.
Generally units are supplied in modular form offering flexibility in arrangements and ease of installation.
Component housing and access sections vary and one or more components can be contained within a section.
The component lengths, shown on selection tables, are maximum and are given for unit selection/planning guidance only.

Flexibility

Sections of different sizes can easily be connected together to suit existing site conditions or restricted plant rooms.

Unit Casing

The unit casing consists of a robust steel framework with flush mounted, double-skinned in-fill panels supported on mild steel channel bases.
The casing is very sturdy and, in its standard design, can withstand internal pressures in excess of 2500Pa.
Two units of the same width can be stacked on top of each other without the need for additional reinforcement.

FANS

Fan Types

Fan sections are generally fitted with double inlet, double width centrifugal type fans with either forward or backward curved blades. Both versions give flexibility and allow the selection of the correct fan for optimum efficiency while obtaining a specified air flow, static pressure and reduced noise levels. Axial and varifoil fans are also available.

Motor Types

Unless otherwise specified, motors are Totally Enclosed Fan Ventilated (TEFV) or drip proof enclosure suitable for operation on three phase power supply.

Externally Mounted Motors

The fan shaft and support base both extend through the unit casing and are fully sealed with a uniquely developed damping device. The motor is fitted externally to the floated base and shaft. Drive guards are fitted as standard.

Motor Options

Dependent upon the requirements of the specification, the following motor options are available,

• Single phase power supply
• Terminal box location
• Run and stand-by facility
• Flameproof motors
• Multi-speed dual wound and pole change motors.