Low Clearance Adapters
Low attic clearance adapters for AirScape Powered AirLock damper boxes. PAL14 adapters are for use with the Sierra 3200 and PAL26 adapters for Sierra 3400 and larger whole house fans. Use when low attic height prevents the duct from being attached directly to the PAL unit.
Note that each adapter is available in a rotated (RLCA) version. They are size specific to the joist/fan orientation and cannot be rotated in the field.
LCA - duct on longer side. RLCA - duct on shorter side.
Powered AirLock damper boxes (PALs) shown in the pictures are NOT included. The low clearance adapters are the sheet metal duct transitions on top of each PAL.
Purchased the Sierra 5300 and, upon installation, found that there was not enough clearance to make the bend in the 20" flex pipe. I ordered and, within a couple days, received the Low Clearance Adapter. It was very easy to install onto the damper box as all the holes were predrilled and in perfect alignment. Although it was a very tight fit, it worked out perfectly. Having this adapter available saved me from having an adapter custom made to complete the installation. Everyone I worked with in Medford was very knowledgeable delivered excellent customer service.