VACH/VAC Linear "Smart" Diffusers

The VACH linear are room temperature controlled outlets. Room air is induced pass the room temperature control thermostatic actuator to vary the discharge open thus varying the volume on both the heating and cooling cycles. A second thermal actuator is located within the supply air path and positions the minimum thermal discharge openings for both the horizontal and the vertical heating cycles.

The VACH is the only linear diffuser that provides single slot VAV vertical heating control. When Warm air is supplied the VACH will automatically adjust to single slot vertical heating position, which increases discharge velocity, thus creating a warm air wash or blanket ideal for perimeter applications. When cool air is supplied the VACH automatically changes direction to a two slot VAV horizontal cooling control diffuser.

The VAC is a two slot VAV horizontal cooling control diffuser; the VAC has the same aesthetic look as the VACH although it is a single function device designed to provide VAV cooling control only.

The patented single blade design provides three openings. The blade pivot point is located to allow the blade to first close the forward opening before the rear opening is fully closed. This reaction results in the VACH diffuser operating as a two slot variable orifice device from 100% to approximately 25% of the maximum demand volume, and as a one slot variable orifice device from 25% to the minimum flow position.

FULL CLOSED VAV ROOM TEMPERATURE CONTROL		ONE SLOT VERTICAL HEATING VAV ROOM TEMPERATURE CONTROL

Eliminates over-heating or over-cooling.

All advantages of vertical heating are enhanced by the automatic discharge opening volume adjustment.

TWO SLOT HORIONTAL COOLING VAV ROOM TEMPERATURE CONTROL

 

Operation:

The VACH is a variable discharge opening diffuser. The room air temperature setting will vary the air supply volume. The operation of the VACH unit will provide room temperature control in the following configurations: vertical-VAV warm air flow; horizontal-VAV cooling air flow. All VAV-linear diffusers are factory calibrated to 72° room temperature plus or minus 2°. If room temperature adjustment is required, turning the room actuator located in the square opening on the face of the unit, clockwise rotation will lower room temperature; counter-clockwise rotation will raise the room temperature.

Cooling Cycle:
Supply air temperature range: approx. 68° or below. Room temperature range: greater than 73° /blade position will respond with appropriate horizontal volume discharge. Room temperature ranges: less than 73° /fully closed blade position.

Heating Cycle Change Over:
Supply temperature range: approximately 85° Room temperature range: greater than 72° /blade position will respond with appropriate vertical volume discharge. Room temperature range: greater than 73° /full closed blade position.

Induction:

Room air induction is created by a simple, but highly effective induction trough. A small amount of supply air is diverted out and through the induction trough at the top of the VACH plenum box. This causes room air to be induced into a small slot at the end of the VACH face. The sample of room air is drawn directly over the thermal actuator.