26026G

What does this component do in a damper linkage assembly?

It is a damper shaft crankarm used to translate the rotary motion of an actuator linkage into damper movement when the actuator cannot be mounted directly on the damper shaft. It forms one of the key lever points in a remote-mounted linkage.

When is an external crankarm used instead of internal damper blade levers?

An external crankarm is typically used when the damper has an accessible external shaft and the linkage is installed outside the damper frame/ductwork. Internal mounting generally relies on damper blade levers rather than an external shaft crankarm.

What other parts are typically required to complete a basic damper linkage with this crankarm?

A basic linkage commonly includes: a damper shaft crankarm (this item, Honeywell 26026G), an actuator-side crankarm, ball joints, and a pushrod. Depending on the installation, a remote mounting kit for the actuator may also be used.

Which ball joint size is commonly paired with this crankarm?

In typical linkage builds, Honeywell ball joint 27518 is used and is sized for a 5/16 in. diameter pushrod. If the application uses a 1/4 in. diameter pushrod, a different ball joint size (such as Honeywell 103598) is used.

What pushrod size is commonly used in the linkage with this crankarm?

A common choice is a 5/16 in. diameter pushrod (for example, Honeywell 25720 series rods), cut to suit the required centre-to-centre distance in the installation.

How is correct linkage geometry typically set for 90° damper travel?

A common approach is to place both the damper and actuator at mid-position, then align the crankarms so they are perpendicular to the imaginary line connecting the centres of the damper and actuator crankarms. Ball joints are then adjusted so they are equidistant from each crankarm centre before tightening.

Can linkage response or damper travel be adjusted using the crankarm arrangement?

Yes. By changing the effective crankarm lengths and linkage geometry, installations can be configured for faster damper response (more damper travel per actuator stroke) or for limited damper travel (less than the actuator stroke), depending on the application needs.

What are common installation constraints that lead to using a linkage crankarm instead of direct coupling?

Typical constraints include dampers installed in wall sections, rooftop units with limited space around the damper frame, replacement of foot-mounted motors, or dampers without provision for direct actuator mounting on an external shaft.

What practical issues should be considered when choosing pushrod length in a linkage?

Very short pushrods can be difficult to adjust, while very long pushrods may lack rigidity and reduce damper responsiveness. Selecting a suitable length and ensuring a rigid linkage helps maintain consistent movement.

Is this crankarm intended to be used on the actuator side or the damper side of the linkage?

This component is intended for the damper side (mounted to the damper shaft) in an external linkage arrangement. The actuator side typically uses a separate actuator crankarm or an actuator mounting kit with the appropriate crankarm.

What checks help ensure full open and full close positions are achieved after installation?

After assembly, exercise the linkage through the full range of travel and verify that the actuator stroke is unobstructed and corresponds to the damper fully open and fully closed positions. If closure is not tight or closes early, adjust the actuator-side ball joint position to fine-tune the effective linkage length, then tighten all joints.

Can this component be used for internal damper mounting applications?

Internal mounting typically uses damper blade levers rather than an external damper shaft crankarm. If the linkage is inside the frame/ductwork and a blade lever is required, a different internal lever component is usually selected instead of this crankarm.