HVAC terminal unit systems and methods
A terminal unit for a heating, ventilation, and/or air conditioning (HVAC) system may include a housing defining a mixing chamber. The mixing chamber may have a primary air inlet, a plenum air inlet, and a mixed air outlet, and mix a primary air flow from the primary air inlet with a plenum air flow from the plenum air inlet to form a mixed air flow that is output through the mixed air outlet to a conditioned space. The terminal unit may also include a panel adjustably coupled to the housing to adjustably occlude the plenum air inlet. The terminal unit may also include an actuator coupled to the housing and the panel to move the panel and adjust a size of an air flow path corresponding to the plenum air inlet.
1 . A terminal unit for a heating, ventilation, and/or air conditioning (HVAC) system, comprising:
a housing defining a mixing chamber including a primary air inlet, a plenum air inlet, and a mixed air outlet, wherein the mixing chamber is configured to mix a primary air flow from the primary air inlet with a plenum air flow from the plenum air inlet to form a mixed air flow that is output through the mixed air outlet to a conditioned space;
a panel adjustably coupled to the housing, wherein the panel is configured to adjustably occlude the plenum air inlet;
an actuator coupled to the housing and the panel, wherein the actuator is configured to move the panel to adjust a size of an air flow path corresponding to the plenum air inlet;
a controller configured to determine a position of the panel corresponding to a reduced noise output of the terminal unit, wherein the controller is configured to determine the position of the panel corresponding to the reduced noise output of the terminal unit based on measured feedback; and
a sensor configured to measure a static air pressure of the primary air flow, wherein the measured feedback comprises the static air pressure.
2 . The terminal unit of claim 1 , comprising a sound attenuator coupled to an exterior surface of the housing about the plenum air inlet, wherein the sound attenuator includes an inlet configured to receive the plenum air flow, and the sound attenuator is configured to direct the plenum air flow to the plenum air inlet of the housing.
3 . The terminal unit of claim 1 , comprising a sound attenuating material disposed on the panel.
4 . The terminal unit of claim 1 , comprising:
an auxiliary coil coupled to the housing and configured to condition the mixed air flow; and
a fan disposed within the housing and configured to motivate air flow through the housing.
5 . The terminal unit of claim 1 , wherein the reduced noise output of the terminal unit comprises a minimized summation of a first noise and a second noise, wherein the first noise is associated with the primary air flow and the second noise is associated with the plenum air flow, wherein the plenum air flow is non-zero.
6 . The terminal unit of claim 1 , wherein the controller is configured to regulate operation of the actuator based on additional measured feedback, wherein the additional measured feedback includes a signal voltage of a fan, wherein the fan is configured to motivate air flow through the housing.
7 . The terminal unit of claim 1 , wherein the actuator is a linear actuator configured to slide the panel along the plenum air inlet.
8 . The terminal unit of claim 7 , wherein the panel is configured to slide along a track coupled to the housing.
9 . The terminal unit of claim 1 , wherein the terminal unit is configured to draw the plenum air flow into the mixing chamber from a plenum space located above a drop ceiling.
10 . The terminal unit of claim 1 , comprising a primary inlet valve configured to regulate a flow rate of the primary air flow into the mixing chamber.
11 . The terminal unit of claim 1 , wherein the controller is configured to select the position, from a plurality of predefined panel positions, having a smallest noise output of the plurality of predefined panel positions.
12 . A terminal unit for a heating, ventilation, and/or air conditioning (HVAC) system, comprising:
a housing defining a mixing chamber including a primary air inlet, a plenum air inlet, and a mixed air outlet, wherein the mixing chamber is configured to mix a primary air flow from the primary air inlet with a plenum air flow from the plenum air inlet to form a mixed air flow that is output through the mixed air outlet to a conditioned space;
a panel adjustably coupled to the housing, wherein the panel is configured to adjustably occlude the plenum air inlet;
an actuator coupled to the housing and the panel, wherein the actuator is configured to move the panel to adjust a size of an air flow path corresponding to the plenum air inlet; and
a controller configured to determine a position of the panel corresponding to a reduced noise output of the terminal unit,
wherein the reduced noise output of the terminal unit comprises a minimized summation of a first noise and a second noise, wherein the first noise is associated with the primary air flow and the second noise is associated with the plenum air flow, wherein the plenum air flow is non-zero.