The LCN 4050A-3049EDA is the OEM Hold Open Extra Duty Arm for the LCN 4050A Series door closer, Grade 1, documented in the LCN Closers and Automatic Operators Parts Manual and the official LCN 4050A Cut Sheet (doc 113107). The arm is handed - left-hand or right-hand must be specified at time of order. Finish must also be specified. The 4050A-3049EDA provides 180 degrees of door swing arc with a hold-open function that is adjusted at the shoe.

The "EDA" in the part number stands for Extra Duty Arm. Per the official LCN 4050A Cut Sheet: the 4050A-3049EDA "features forged, solid steel main and forearm for potentially abusive installations."

What Extra Duty Means on the 4050A-3049EDA

Standard closer arms are typically made from cast or formed steel. The 4050A-3049EDA uses forged solid steel for both the main arm and the forearm - both pieces of the two-part arm assembly. Forging is a manufacturing process where steel is shaped under high pressure rather than cast or machined. Forged steel is denser and more resistant to impact, bending, and fatigue than cast steel of the same dimensions.

LCN specifically calls out "potentially abusive installations" as the application target for the EDA arm. These are doors where:

High-traffic conditions push the arm through thousands of cycles per day rather than the standard commercial cycle count. Schools, hospital corridors, and government building entrances where the door never stops moving fall into this category.

Vandalism or rough use is a realistic expectation - loading dock exits, correctional facility doors, mental health facility corridors, and any application where door hardware gets physically abused over its service life.

Heavy doors or wide openings put more mechanical stress on the arm during each cycle - the closer has to work harder to control the door, which puts more load through the arm joints and the connection points.

The forged steel construction handles all three conditions better than a standard stamped or cast arm would. The material resists the bending and fatigue that accumulate in high-stress applications.

LCN 4050A Series: Hold-Open Function and 180-Degree Swing

The hold-open function on the 4050A-3049EDA is adjusted at the shoe - the fitting at the end of the arm that connects to the door or soffit (track stop). The shoe adjustment sets the angle at which the arm holds the door open. This field adjustment capability means the hold-open position can be calibrated to the specific door opening geometry during installation and recalibrated if the building geometry changes.

The 180-degree swing is the full-arc capability of this arm. Most standard closer arms limit door swing to 95 to 110 degrees. The 180-degree swing allows the door to open completely - door face parallel to the adjacent wall or return - without the arm reaching its mechanical limit and creating resistance before full open. This matters on high-traffic doors where people push through quickly and where partial door opening would create a bottleneck.

LCN 4050A Door Closer Parts: EDA Arm Family

The 4050A arm catalog includes several configurations for different installation requirements. Per the LCN 4050A Cut Sheet, the complete arm family for this series:

4050A-3049EDA (this product) = Hold-open extra duty arm, handed, forged steel, hold-open adjusted at shoe.

4050A-3049EDA/62G = Hold-open extra duty arm with 62G feature - the same forged steel construction with an additional 62G stop/hold-open capability.

4050A-3049CNS = HCUSH arm - provides hold-open with templated stop/hold-open points; handle controls hold-open function.

4050A-3077SCNS = Spring CUSH arm - non-handed, forged solid steel main arm and forearm, spring-loaded stop in the soffit shoe.

4050A-3049L = Long hold-open arm - non-handed, includes the 4050A-3048L long head and tube for top jamb mounting.

The 4050A-3049EDA is the standard heavy-duty hold-open arm for hinge-side and parallel arm mounting. Confirm the handing and installation type before ordering.

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