FV-TS

The SEMCO FV-TS system is a packaged system that includes supply and exhaust air fans, outdoor and return air filters, and SEMCO's Total Energy Composite (TEC) total energy recovery wheel. The TEC wheel recovers both sensible (temperature) and latent (moisture) energy; it cools and dehumidifies the outdoor air during the cooling season while heating and humidifying the outdoor air in the heating season.

The TEC wheel utilizes a fluted aluminum substrate that is uniformly coated with a fast-acting, adsorbent desiccant. As the transfer media slowly rotates between the outdoor and exhaust airstreams, the higher temperature air gives up its sensible energy to the aluminum. This energy is then given up to the cooler air stream during the second half of the revolution. Just as the temperature is captured and released, so is the moisture. The wheel's desiccant coating has an enormous internal surface area and a strong attraction for water vapor. Since the opposing airstreams have different temperature and moisture contents, their vapor pressures differ. This difference causes the transfer of latent energy.

• Novel System Design
  • Efficient and economical design meeting the needs of the conventional HVAC market.
  • Compact, low profile design to conform to typical architectural requirements.
  • Easy access to all internal components through a large hinged access door and removable roof panel.
  • Outdoor air inlet and exhaust air outlet located at opposite ends of unit for maximum separation.
• The TEC Total Energy Wheel
  • Certified total energy (both sensible and latent) recovery performance.
  • Easily removable wheel cassette module.
  • Surpasses NFPA-90A requirements having a smoke and flame spread rating of 0 and 0, vs. 50 and 25 allowed by the standard.
  • Self-adjusting air seals.
• Cabinet Construction
  • Galvanized steel cabinet construction with enamel finish.
  • Entire cabinet insulated to minimize energy loss.
  • Hinged doors for easy access.
  • Floor of the unit built as a pan to ensure watertight design.
• Supply and Exhaust Air Fans
  • Sized for quiet and efficient operation.
  • Mounted and balanced.
  • Multiple speed motors or multiple motor/sheave selections for efficient adjustment of airflow.
• Filter Sections
  • Filtration provided for both the outdoor air and return air.
• Hoods and Dampers
  • Airflow balancing dampers.
  • Unit provided with an intake hood with cleanable filter to limit rain and snow introduction.
  • Exhaust air back draft damper on outside units only.

For information about features go to Semco´s website >>

Economical Compliance With ASHRAE Standard 62

• To achieve acceptable indoor air quality, ASHRAE Standard 62 recommends a three-to-four-fold increase in the amount of outdoor air provided to most facilities. In addition, ASHRAE recommends that this increased outdoor air quantity be introduced continuously while spaces are occupied. By recovering up to 80 percent of the total energy normally exhausted from facilities, FV-TS preconditioning allows conventional HVAC systems to effectively handle this increase in outdoor air load without increasing the size of the heating/cooling capacity while decreasing energy consumption.

Reduced Equipment First Cost

• Without the addition of effective energy recovery, the capacity of HVAC systems must be increased significantly to handle the greater outdoor air loads associated with higher ventilation rates. Increasing equipment size often requires the addition of reheat and sophisticated control sequences to control humidity as well as temperature. The FV-TS preconditioner often reduces project first cost by allowing smaller HVAC units and duct systems to be used without the need for reheat or complex controls.

Improved Cooling Season Humidity Control

• A thermostat governs operation of conventional HVAC systems, i.e., in response only to the conditioned space temperature. When the cooling coil is cycled off, the outside air fan is typically shut-off as well. Thus, no ventilation is provided to the conditioned space until the thermostat calls for cooling. If the outside air fan is allowed to run while the cooling coil is off, then warm, humid air is directed to the space. In both of these cases, indoor space humidity levels will increase above guideline levels, i.e., 60 percent relative humidity.
• Since the FV-TS Preconditioner dehumidifies and cools the incoming outdoor air, the supply air conditions are close to the return air conditions. This effectively produces a buffer against high outdoor latent loads resulting in acceptable indoor humidity levels.

Helps Reduce Humidification Requirements During the Heating Season

• Supplying 15 to 20 cfm/person of cold, dry outdoor air to a facility during the heating season can result in unacceptably low indoor relative humidity. The HVAC system effectively maintains space temperature by heating the air, yet few facilities are humidified. It is now well documented that many wintertime illnesses come as a result of the body's inability to fight off infection due to "dry airways." The FV-TS unit captures the moisture generated within the space to provide free humidification during the heating season therefore maintaining a healthier indoor environment.

Improves the IAQ of Existing Facilities

• The compact yet versatile design of the FV-TS unit allows for easy installation in existing facilities and eliminates additional ductwork and disruption of the occupied space below. It can either be used as a stand-alone unit serving multiple HVAC units or as a dedicated preconditioner ducted directly to a single unitary HVAC system.

Improves the Comfort of Occupied Spaces

• As the outdoor air is supplied to the space, the heating/cooling source is cycled on and off to maintain temperature. When it is cycled off, very cold or very warm/humid air can be "dumped" on the occupants, causing wide temperature fluctuations that makes for a very uncomfortable environment. FV-TS preconditioning solves this problem by providing moderated supply air conditions, even as the heating/cooling source is cycled on and off.

CASING - Standard panels shall be 20 gauge galvanized steel. The housing shall be supported by a formed structural base that forms a pan to ensure weather tight construction. Lifting holes shall be provided at the unit base. Units shall have a weatherproof sheet metal roof. Insulation shall be ½” thick closed-cell neoprene for wash down capability and include antimicrobial protection. Insulation shall meet or exceed requirements of UL 181, ASTM G21/C 1338 and ASTM G 22 for resistance to mold, fungi and bacteria. The outdoor air intake opening shall be protected by a galvanized steel sheet metal weather hood and include an automatic rotary blade damper with blade seals and an electric actuator. The exhaust air discharge shall be covered with a gravity back draft damper and weather hood. The exterior of the unit shall be coated with an epoxy primer and a polyurethane enamel painting system for added protection. Painting system shall be rated to meet a 1500-hour salt spray test.

ACCESS - Access to components shall be provided through a large, tightly sealed and easily removable access panel. Access panels shall be constructed of the same materials as the unit casing and use SEMCO's standard hardware. The wheel cassette shall be easily removable from the unit. The roof of the unit shall also be removable for access.

UNIT CONFIGURATION - The supply air inlet and exhaust air outlet must be oriented at opposite ends of the Energy Recovery System to maximize the distance between the two airstreams in order to minimize the risk of short circuiting exhaust air into the supply air intake.

FANS - Fans shall be double width double inlet design with forward curve type wheels. The blades shall be designed for maximum efficiency and quiet operation. Impellers shall be statically and dynamically balanced.

Fans shall be driven by direct drive motors located at the fan inlet or by motors using belts and sheaves. Motors shall be standard NEMA frame with open drip-proof enclosures. V-belt drives shall be designed for a minimum 1.2 service factor.

TOTAL ENERGY WHEEL - The rotor media shall be made of aluminum that is coated to prohibit corrosion. The rotor media shall be coated with a non-migrating adsorbent to transfer water vapor and to prohibit corrosion. Equal sensible and latent recovery efficiencies shall be clearly documented through a certification program conducted in accordance with ASHRAE 84 and ARI 1060 standards. The media shall be cleanable with low temperature steam, hot water or light detergent, without degrading the latent recovery. Dry particles up to 600 microns shall freely pass through the media. Wheel media shall be independently tested and shown to have a flame spread of less than 25 and a smoke generation rating of less than 50 when tested in accordance with ASTM E84.

ROTOR CASSETTE - The rotor cassette shall be a sheet metal framework that limits the deflection of the rotor due to air pressure. The cassette shall be made of galvanized steel to prevent corrosion. The rotor cassette shall be easily removable from the Energy Recovery Unit to facilitate rigging (if necessary) and ease of service. The wheel cassette design shall use pillow block bearings for long life. A non-adjustable purge sector shall be included in the cassette.

AIRFLOW MONITOR - Unit shall include an integral airflow monitoring station with the ability to read both ventilation and exhaust airflow expressed in CFM. Monitor gauge to be flush mounted on unit exterior and watertight.

FILTERS - The filters shall be 1 inch thick permanent aluminum washable type mounted in the outside air hood and in the return air plenum. The filters shall be listed by Underwriters' Laboratories as Class 2.

Optional Rotation Detector - Unit shall be equipped with a rotation sensor and controller such that should the energy recovery wheel not rotate during a signaled run period, the controller shall send a 24 volt AC signal suitable for operating a relay to be used as an alarm contact. The controller shall not initiate an alarm during a stop/jog function.

Optional Stop/Jog Economizer - Unit shall be equipped with an outdoor air temperature sensor and controller such that the energy recovery wheel can be stopped during moderate temperature periods. The controller shall perform a stop/jog function for the wheel long enough to promote the self-cleaning features of the wheel but not long enough to induce energy recovery.

Optional Wheel Stop/Jog Frost Protection - Unit shall be equipped with an outdoor air temperature sensor and controller such that the energy recovery wheel can be operated in stop/jog mode during very low outdoor air temperature periods to prevent freezing of the wheel while still delivering outdoor air through the unit.

Optional Remote Indicating Panel – Panel shall provide remote indication of status of unit power on, wheel rotation alarm, outside air dirty filter and return air dirty filter. Low voltage LED’s will be illuminated for power on, wheel stop, filter pressure drop exceeding 0.8” w.c. LED’s are factory mounted in a brushed aluminum faceplate with identification label and are factory wired to a terminal strip. Panel includes a junction box and plaster ring for either recessed or surface mounting. FV-TS unit will include factory mounted pressure switches and electrical components wired to a terminal strip located in an exterior weatherproof junction box. Field wiring between the FV-TS unit and the remote panel using Belden 5 conductor 8465 (20-gauge) or equivalent.

Optional Dual Wall Construction – Unit shall be equipped with an interior liner of 22 gauge galvanized sheet metal.

Optional Electric Preheat Coil - Coil shall be of the resistance coil type with elements enclosed in a steel sheath with fins and painted with a baked-on aluminum paint for long life in a 100% fresh air stream. Coil shall include thermal cutout protection with automatic primary protection and a secondary manual reset linear thermal cutout. Coil shall have magnetic safety and backup contactors, main disconnect, fusing, control circuit transformer, airflow interlock switch and SCR controller. Coil shall be UL listed and constructed in accordance with NEC requirements. A temperature controller located in the outdoor air section of the unit shall supply the signal to the SCR controller.

Optional Freeze Protection Thermostat - Unit shall be equipped with an outdoor air temperature thermostat such that the energy recovery ventilator can be stopped during very low temperature periods. This thermostat shall stop both the fans and the energy recovery wheel until the outdoor air temperature rises above the set point, then the unit will restart automatically.

ELECTRICAL - Units shall require a single 60-cycle power connection. See schedule for voltage and phase requirements. The electrical panel shall consist of individual motor contactors, short circuit, and overload protection and control power transformer. The NEMA 3R electrical panel shall be mounted on the unit exterior for ease of access. Unit shall be ETL listed and labeled.

SOLE AND EXCLUSIVE WARRANTY - SEMCO warrants to Buyer that for a period of eighteen months from the date of shipment by SEMCO the goods to be delivered to 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 eighteen 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 parts or by making available at SEMCO's plant a repaired or replacement part.