Wording for ARI Certified Wheels, Options and Accessories
ARI Certified Energy Recovery Wheels
Wheel shall be of the enthalpy type for both sensible and latent heat
recovery and be designed to insure laminar flow. Energy transfer ratings
must be ARI Certified to Standard 1060 and bear the ARI certification
symbol for ARI Air-to-Air Energy Recovery Ventilation Equipment Certification
Program based on ARI 1060. Ratings "in accordance with 1060" without certification
are not acceptable. Desiccant shall be silica gel for maximum latent energy
transfer. Wheel shall be constructed of lightweight polymer media to minimize
shaft and bearing loads. Polymer media shall be mounted in a stainless
steel rotor for corrosion resistance.
Wheel design shall consist of removable segments (on diameters 36 inches
and greater) for ease of service and/or cleaning. Silica gel desiccant
shall be permanently bonded to wheel media to retain latent heat capability
after cleaning. Wheels with sprayed on desiccant coatings are not acceptable.
Wheels with desiccant applied after wheel formation are not acceptable.
Energy recovery device shall transfer moisture entirely in the vapor phase.
Energy recovery drive belt material shall be high strength urethane and
shall be factory installed in a pre-stretched state, eliminating the need
for field belt tension adjustment. Link style belts are not acceptable.
ERT with Wrap Around Heat Pipe for Neutral Temperature Applications
Dehumidifier heat pipe shall precool the air leaving the wheel and reheat
the air leaving the cooling coil in a wrap around configuration. Both
heat exchangers shall be inside and integral to the equipment cabinet.
Coils shall have copper tubes with permanently expanded aluminum fins,
12 fpi or less. Heat transfer fluid shall be classified as Safety Group
A1 in BDR/ASHRAE Std. 15- 1989R.
Gas Heat Option with ERH and ERCH
Indirect fired gas furnace shall be 80% efficient, UL Listed
for indoor and outdoor installation to ANSI Standard Z83.8 - 2002,
CGA approved per 2.6 - 2002 and have a blow through fan design.
Furnace shall be capable of operation with natural gas or LP gas
and have a power venting system. The burner and heat exchanger
shall be constructed of aluminized steel. Standard furnace features
shall include main gas pressure regulator, main gas valve, electronic
staged or electronic modulating controls, direct spark ignition
system, high limit and a 24-volt control transformer.
Night Setback Option with ERCH
Night setback damper shall allow air recirculation during unoccupied
hours. Night setback damper shall be located in the divider between the
supply and exhaust airstreams after the energy recovery wheel and before
the tempering coils. Night setback damper shall be of low leakage design
with thermally insulated airfoil blades, stainless steel jamb seals, and
extruded silicone rubber blade seals.
Modulating Energy Recovery Wheel
Energy recovery wheel shall be supplied with a fully factory programmed
variable frequency drive. Outdoor air and return air sensors shall trigger
wheel modulation for economizer mode. Outdoor air sensor and wheel pressure
drop sensor shall trigger wheel modulation for frost control mode. Wheel
shall modulate to target a discharge temperature of 55F during economizer.
Wheel shall modulate during frost control to eliminate frost.
Real Time Frost Control
Frost control shall be triggered by an outdoor air temperature sensor
AND a wheel pressure drop sensor. Both sensors are to be satisfied
to employ frost control. Frost control strategies employed via outdoor
air temperature sensor only are not acceptable.
Demand Control Ventilation
Demand control ventilation shall be triggered by a factory supplied carbon
dioxide sensor monitoring CO2 levels in the space. The CO2 sensor shall
provide unit on-off control, blower low speed high speed control, or
blower modulation control. CO2 sensor shall be factory preset and field
adjustable.