Carrier EW, 48EJ, EK, EY024-048 Ð Barometric Relief Damper and Power, Exhaust Mounting Details

Step 10 Ð Position Power Exhaust/Barometric Relief Damper Hood Ð All electrical connections have been made and adjusted at the factory. The power exhaust blowers and barometric relief dampers are shipped as- sembled and tilted back into the unit for shipping. Brackets and extra screws are shipped in shrink wrap around the damp- ers. If ordered, each unit will have 4 power exhaust blowers and motors or 4 barometric relief dampers.

1.Remove 9 screws holding each damper assembly in place. See Fig. 37. Each damper assembly is secured with 3 screws on each side and 3 screws along the bottom. Save screws.

Be careful when tilting blower assembly. Hoods and blow- ers are heavy and can cause injury if dropped.

2.Pivot each damper assembly outward until edges of damper assembly rest against inside wall of unit.

3.Secure each damper assembly to unit with 6 screws across top (3 screws provided) and bottom (3 screws from Step 1) of damper.

4.With screws saved from Step 1, install brackets on each side of damper assembly.

5.Remove tape from damper blades.

VAV DUCT PRESSURE TRANSDUCER Ð The VAV duct pressure transducer (VAV inverter pressure transducer) is lo- cated behind the ®lter access door on the lower inner panel.

See Fig. 38. A section of ®eld-supplied 1¤4-in. plastic tubing must be run from the high pressure tap on the differential pressure switch and connected to a ®eld-supplied tap in the supply-air duct. The tap is usually located 2¤3 of the way out on the main supply duct. Remove plug button in panel to route tubing.

The low pressure tap is factory-routed to the atmo- sphere. For a positive-pressure building, route the high tap to building air and low tap to atmosphere. For a negative- pressure building, route the high tap to atmosphere and the low tap to building air.

VAV BUILDING PRESSURE TRANSDUCER Ð The VAV building pressure transducer (modulating power exhaust pres- sure transducer) is located behind the ®lter access door on the lower inner panel. See Fig. 38. A section of ®eld- supplied 1¤4-in. plastic tubing must be run from the high pres- sure tap on the differential pressure switch to the conditioned space. The pressure tube must be terminated in the condi- tioned space where a constant pressure is required. This lo- cation is usually in an entrance lobby so that the building exterior doors will open and close properly. Remove plug button in panel to route tubing.

The low pressure tap is factory-routed to the atmo- sphere. For a positive-pressure building, route the high tap to building air and low tap to atmosphere. For a negative- pressure building, route the high tap to atmosphere and the low tap to building air.

NOTES:

1.Unless otherwise speci®ed, all dimensions are to outside of part.

2.Dimensions are in inches.

3.On 48EW,EY units, accessory barometric relief or power exhaust must be mounted in the ®eld-supplied return ductwork.

Fig. 37 Ð Barometric Relief Damper and Power

Exhaust Mounting Details

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