JCI VMA 1410 or 1420 Replacement Bushing

Hundreds of thousands of Johnson Controls (JCI) Metasys VMA-1410 and VMA-1420 Variable Air Volume (VAV) controllers exist across the world. Hardware wise these controllers are very reliable however the common point of failure after about 15-20 years of use is a small bushing that joins the drive motor to the first stage of gear reduction. Once this bushing breaks the controller cannot open or close the damper.

These controllers are no longer being manufactured and if you can find a replacement controller they cost around 400 dollars. However, if you remove 4 screws you can replace the failed bushing in about 10 minutes restoring normal operation again for another 10-20 years.

Instead of reproducing the original failed bushing design this bushing is over-built to be much stronger and will never fail again. If printing on a SLA printer only use strong resins such as Sirya Blue or stronger and then cure in the sun. If printing on a FDM printer I would only use PETG filaments due to strength and minor pliability. The gap spacing for all mating parts is 0.1 mm which will produce parts that are snug and but not loose.

If FDM printing doing so with 0.2mm layer height will maximize the layer adhesion and overall strength. Install the bushing first to the motor, pressing firmly, just so that the hex head is inside the bushing then pressing the whole motor and bushing down onto the white gearhead will seat the bushing at the perfect depth.

The STL and original Fusion 360 files are attached for any possible modifications that you would like. -enjoy

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