Total Energy Recovery Wheel Unit - The rotor media must be made of aluminum that is coated to prohibit corrosion; etched or oxidized surfaces are not acceptable. All surfaces must be coated with a non-migrating adsorbent layer prior to being formed into the honeycomb media structure to ensure that all surfaces are coated and that adequate latent capacity is provided.

The desiccant must be specifically designed for the adsorption of water vapor. Verification in writing must be presented from the desiccant manufacturer confirming that the internal pore diameter distribution inherent in the desiccant being provided limits adsorption to materials not larger than the critical diameter of a water molecule (2.8 angstroms). The desiccant utilized shall be a 3Å molecular sieve.

Equal sensible and latent recovery efficiencies must be clearly documented through a certification program conducted in accordance with ASHRAE 84-78P and ARI 1060 standards. The certification must have been conducted by a qualified independent organization.

Independent wheel testing to document that the desiccant material utilized does not transfer pollutants typically encountered in the indoor air environment shall be provided from a credible test laboratory. The cross-contamination and performance certification reports must be provided for engineering review as part of the submittals for this project.

The wheel manufacturer must have been producing the wheel product for a minimum of five years and must provide references with a successful operating history of at least four years.

The media shall be cleanable with low temperature steam, hot water, or light detergent without degrading the latent recovery. Dry particles up to 800 microns shall pass freely through the media.

Purge Sector - The unit must be provided with a factory set, field adjustable, purge sector designed to limit cross-contamination to less than .04 percent of that of the exhaust air stream concentration when operated under appropriate design conditions.

Rotor Seals - The rotor shall be supplied with labyrinth seals, which at no time are required to make contact with any rotating surface of the exchanger media. These multipass seals shall utilize four labyrinth stages for optimum performance.

Rotor Support System - The rotor media must be provided in segmented fashion to allow for field erection or replacement of one section at a time. The media shall be rigidly held by a structural spoke system made of extruded aluminum.

Protective Face Coating for Enthalpy Wheel - In addition to the desiccant coating applied to the surface of the aluminum substrate prior to being formed into the total energy wheel media (i.e. no dipped or oxidized coatings), the two faces of the total energy wheel shall be covered and sealed with a two part polymer heavy duty coating specifically chosen for chemical resistance.

Drive System - The rotor must be driven by a self-adjusting belt system. An A/C motor is utilized for constant and variable speed applications.

Temperature Control Panel - If variable speed control is required, it must be accomplished by the use of an AC drive, including local start/stop control, manual speed pot and all digital programming. The drive system will allow for a turndown ratio of 80:1 (20 rpm to 1/4 rpm). The control system will include four temperature sensors as follows:

• proportional temperature controller mounted in the supply air stream;
• differential summer/winter changeover sensors mounted in the outdoor and return air streams;
• frost prevention sensor located in the exhaust air stream.

Rotation Detector - A 24VAC rotation detector sensor will be mounted at the wheel and wired to the detector in the main electrical panel.

Sole and Exclusive Warranty - SEMCO warrants to buyer that for a period of 18 months from date of shipment by SEMCO, the goods to be delivered to the buyer will in all material respects be free from defects in material and workmanship when used in a proper and normal manner. Should any failure to conform to the above appear within 18 months after the date of shipment by SEMCO (the “Limited Warranty Period”), SEMCO agrees upon prompt notification thereof during the Limited Warranty Period and confirmation to SEMCO’s satisfaction that the goods have been stored, installed, operated and maintained properly and in accordance with standard industry practice, to correct the non-conformity at SEMCO’s option either by repairing any defective part or by making available at SEMCO’s plant a repaired or replacement part.