Applications Considerations
When using an IntelliPak II Air Handler for horizontal supply and/or return, an additional pressure drop must be added to the supply external static to account for the 90 degree turn the air is making. This additional pressure drop depends on airflow and air handler size, but a range of
0.10inches to 0.30 inches can be expected. The openings on the air handler all have a one inch lip around the perimeter to facilitate ductwork attachment.
Corrosive Atmospheres
Trane's IntelliPak II Air Handlers are designed and built to industrial standards and will perform to those standards for an extended period depending on the hours of use, the quality of maintenance performed, and the regularity of that maintenance. One factor that can have an adverse effect on unit life is its operation in a corrosive environment.
Because copper is more resistant to corrosion than aluminum, coil life expectancy is greatly increased.
Ventilation Override
Sequences
One of the benefits of using an exhaust fan rather than a return fan, in addition to the benefits of lower energy usage and improved building pressurization control, is that the air handler can be used as part of a ventilation override system. Several types of sequences can be easily done when exhaust fans are a part of the air handling system.
What would initiate the ventilation override control sequence? Typically, a manual switch is used and located near the fire protection control panel. This enables the fire department access to the control for use during or after a fire. It is also possible to initiate the sequence from a field- installed automatic smoke detector. In either case, a contact closure begins the ventilation override control sequence.
CAUTION!
The ventilation override system should not be used to signal the presence of smoke caused by a fire.
Trane can provide five (5) different ventilation override sequences on both CV and VAV IntelliPak II Air Handlers. For convenience, the sequences are factory preset but are fully field edited from the Human Interface Panel or Tracer™. Any or all five sequences may be “locked” in by the user at the Human Interface Panel.
The user can customize up to five (5) different override sequences for purposes such as smoke control. The following parameters within the unit can be defined for each of the five sequences:
•Supply Fan - on/off
•Inlet Guide Vanes - open/closed/ controlling
•Variable Frequency Drives - on (60 Hz)/off (0 Hz)/controlling
•Exhaust/Return Fan - on/off
•Exhaust Dampers - open/closed
•Economizer dampers - open/ closed
•Heat - off/controlling (output for) VAV Boxes - open/controlling
Factory preset sequences include unit Off, Exhaust, Purge, Purge with duct pressure control, and Pressurization. Any of the user- defined Ventilation Override sequences can be initiated by closing a field supplied switch or contacts connected to an input on the Ventilation Override Module. If more than one ventilation override sequence is being requested, the sequence with the highest priority is initiated. Refer to the Ventilation Override Module (VOM) page 17 in the Control section of this catalog for more details on each override sequence.
Natural Gas Heating
Considerations
Trane uses heavy gauge 304 L stainless steel throughout the construction of its natural gas drum and tube heat exchangers for the IntelliPak II product. These heat exchangers can be applied with confidence, particularly with full modulation control, when mixed air temperatures are below 50°F, and low ambient temperatures can cause condensation to form on the heat
exchanger. IntelliPak II natural gas heat exchangers are not recommended for applications with mixed air conditions entering the heat exchanger below 30°F to insure adequate leaving air heating temperature.
For airflow limitations and temperature rise across the heat exchanger information, see Table 27, p. 70.
Acoustical Considerations
The ideal time to make provisions to reduce sound transmission to the space is during the project design phase. Proper placement of air handler equipment is critical to reducing transmitted sound levels to the building. The most economical means of avoiding an acoustical problem is to place any air handler equipment away from acoustically critical areas. If possible, air handling equipment should not be located directly above areas such as: offices, conference rooms, executive office areas and classrooms. Ideal locations are above corridors, utility rooms, toilet facilities, or other areas where higher sound levels are acceptable.
Several basic guidelines for unit placement should be followed to minimize sound transmission through the building structure:
1
Locate the unit's center of gravity close to or over a column or main support beam to minimize roof deflection and vibratory noise.
2
If the roof structure is very light, roof joists should be replaced by a structural shape in the critical areas described above.
3
If several units are to be placed on one span, they should be staggered to reduce deflection over that span.
It is impossible to totally quantify the effect of building structure on sound transmission, since this depends on the response of the roof and building members to the sound and vibration of the unit components. However, the guidelines listed above are experience proven guidelines which
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