gas burner.
]2.1.3
Sensible Heat Recovery Devices
[2.1.3.1
Rotary Wheel
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NOTE: Select minimum acceptable energy transfer
effectiveness and maximum acceptable
cross-contamination. Delete moisture resistance and
chain drive if not required.
**************************************************************************
Unit shall be a factory fabricated and tested assembly for air-to-air
energy recovery by transfer of sensible heat from exhaust air to supply air
stream. Device performance shall be according to ASHRAE 84. Device shall
deliver energy transfer effectiveness of not less than [70] [85] [_____]
percent with cross-contamination not in excess of [0.1] [1.0] [_____]
percent of exhaust airflow rate at system design differential pressure.
Exchange media shall be chemically inert, moisture resistant,
fire-retardant, laminated, nonmetallic material which complies with NFPA 90A.
Exhaust and supply stream shall be isolated by seals which are static,
field adjustable, and replaceable. Chain drive mechanisms shall befitted
with racheting torque limiter or slip-clutch protective device.
Enclosure
shall include maintenance access provisions. Recovery control and
rotational failure provisions shall be as indicated.
][2.1.3.2
Heat Pipe
**************************************************************************
NOTE: Schedule should include face air velocity,
static pressure drop, temperature requirements for
entering and leaving air or exhaust streams. Delete
flexible connectors if not required.
**************************************************************************
Device shall be a factory fabricated, assembled and tested, counterflow
arrangement, air-to-air heat exchanger for transfer of sensible heat
between exhaust and supply airstreams. Device shall deliver an energy
transfer effectiveness not less than that indicated without
cross-contamination. Heat exchanger tube core shall be [15] [18] [25] mm
[1/2] [5/8] [one] inch nominal diameter, seamless aluminum or copper tube
with extended surfaces, utilizing wrought aluminum Alloy 3003 or Alloy
5052, temper to suit. Maximum fins per unit length and number of tube rows
shall be as indicated. Tubes shall be fitted with internal capillary wick,
filled with an ASHRAE 15, Group 1 refrigerant working fluid, selected for
system design temperature range, and hermetically sealed. Heat exchanger
frame shall be constructed of not less than 1.6 mm 16 gage galvanized steel
intermediate tube supports, and flange connections. Tube end-covers and a
partition of galvanized steel to separate exhaust and supply air streams
without cross-contamination shall be provided. [A drain pan constructed of
welded Type 300 series stainless shall be provided.] Heat recovery
regulation shall be provided by [system face and bypass dampers and related
control system as indicated] [interfacing with manufacturer's standard
tilt-control mechanism for summer/winter operation, regulating the supply
air temperature and frost prevention on weather face of exhaust side at
temperature indicated]. Coil shall be fitted with pleated flexible
connectors.
SECTION 15751N
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