Greenheck Fan APEX-200 Sequence of Operation, Basic Unit, Summer Operation, Winter Operation

Sequence of Operation

Basic Unit

The APEX unit is pre-wired such that when a call for outside air is made (via field supplied 24 VAC control signal wired to unit control center), the supply fan, exhaust fan and energy wheel are energized and the motorized dampers open. The APEX unit can be supplied with or without heating and cooling coils. For units with coils, controls can be supplied by Greenheck (refer to the Temperature Control IOM, Part #461468, for sequence of operation) or by the controls contractor. If supplied by the controls contractor, they would provide, mount, and wire any temperature controllers and temperature or relative humidity sensors required for the unit to discharge air at the desired conditions.

Summer Operation

Outdoor air is preconditioned (temperature and moisture levels are decreased) by the transfer of energy from the cooler, drier exhaust air via the energy recovery wheel.

Units supplied with cooling coils can further cool the air coming off the wheel and strip out moisture to levels at or below room design. A heating coil downstream of the cooling coil can reheat the air to a more comfortable discharge temperature to the space.

Economizer Operation: See Economizer Application/Operation section

Winter Operation

Outdoor air is preconditioned (temperature and moisture levels are increased) by the transfer of energy from the warmer, more humid exhaust air via the energy recovery wheel.

Units supplied with heating coils can further heat the air coming off the wheel to levels at or above room design.

Frost Control Operation: See Frost Control Application/Operation section

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