Trane TRG-TRC014-EN manual Answers

Answers

1a 1,382 cfm [0.65 m3/s]

1b 63°F [17.2°C]

1c 829 cfm [0.39 m3/s]

2The reduced airflow across the cooling coil at part load causes the refrigeration system to throttle back in order to stabilize the supply air temperature condition. IN turn, this results in a reduction in refrigeration energy.

3Variable thermal load profiles in the spaces, the need for multiple, independently-controlled spaces, and the existence of a common return air path

4Series, fan-powered VAV

5The air in the ceiling plenum is warmer than the space because it contains heat from the building and lights.

6A pressure-independent VAV control scheme directly controls the actual volume of primary air that is flowing to the space. The position of the modulation device is not directly controlled and is basically a by-product of controlling the actual airflow through the unit. Because the airflow delivered to the space is directly controlled, this airflow is independent of the inlet static pressure.

7Coanda effect

8Baseboard, or under-the-window, heating

9A constant-volume supply fan

10Inlet vanes modulate the capacity of a fan by “pre-swirling” the air in the direction of fan wheel rotation, before it enters the wheel. By changing the angle of air entry into the fan, these modulating inlet vanes lessen the ability of the fan wheel to “bite” the air.

11Optimized static-pressure control

12ASHRAE Standard 62–1999

13Draining the coils during cold weather, keeping the water in motion, adding glycol to the water, using face-and-bypass dampers to limit the amount of cold airflow through the coil, or preheating the outdoor air

86 TRG-TRC014-EN