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Retrozone and Flexdamper are trademarks of Retrozone inc.

 38398L,37923L, 37729L, 37339L

Synchron Motors

 Fit Retrozone and Damperdirect 3150 

Replacement Damper and Others


Synchron 38398L, 37923L, 37729L, 37339L damper motor, yellow wire damper motor, two wire damper motor, Ztech, Buetler, Hansen
Synchron 38398L, 37923L, 37729L, 37339L damper motor, yellow wire damper motor, two wire damper motor, Ztech, Buetler, Hansen


This motor will work for many round, as well as rectangular dampers, as long as it has the number 38398L, or 37729L, or 37339L on the side of the motor. Do not order unless you see that number, there are many motors that look like this from the back side.

*Restock Charge: Please note our 15% restock charge on this motor due to excessive returns due to not matching the motor numbers (see above), this motor will not work for you unless the numbers match as stated above, even if it looks just like your motor. *Buyer pays return shipping in all cases.

*This motor may replace your old motor IF the drive or output shaft is identical to pictures, and the 5 digit number ends with the letter 'L" (meaning left hand rotation) , and its 24volts ac. Do not order if the 5 digit number ends in "R", that means "right hand rotation" and the motor will not work for you, even if it looks identical.

* You must either match the numbers, or visually the output shaft. Synchron made hundreds of motors that look the same from the motor side, but are not interchangeable, you must verify the 5 digit number. Thanks! * Cant find the right motor? Check our Belimo powered retrofit kits, that allow the outstanding Belimo commercial damper motors to be retrofitted back on to many types of existing dampers with dead motors. Belimo is the largest maker of commercial damper motors in the world.

* You may also call us direct at 972-633-8104 and we’ll be happy to help you find the right replacement motor for you.

*If you purchased one of our round, or rectangular 3150 series spring return dampers from our website, Retrozone.com, then this is the motor you need as a replacement.

*This same motor has been used on other types and brands of dampers, including Enerstat, Lennox, Jackson Controls, Robert Shaw and others. Please do be aware some dampers use similar motors but the shaft dimensions are different, and that’s why we include those dimensions here. But, if you are looking for a motor to replace one on a spring return rectangular damper purchased from us, THIS IS the correct motor. For other applications, this motor says on its side "645 24V 60HZ 6W 60RPH 38398L-5-6-46" A yellow label may be attached that says "P/ N 78G1001 24VAC .44 amp 60HZ" This motor is designed to operate on 24 volts ac only. If you have any technical questions you may call us at 972-633-8104. We have most replacement motors for many brands of dampers, as well as some universal fit replacements. All motors are new inventory, 1 year warranty, and come with full service and support. From Retrozone.com, where zoning is our only business! We offer the service, support, and technical resources to help you design or service your Zone Control System. We handle all major brands including Durozone, Honeywell, EWC, Retrozone, Enerzone Systems Corp., Robertshaw, Invensys and more

Retrozone and Damperdirect 3150 Replacement Damper motors

We also offer two Belimo retrofit kits designed to replace the 38572R. These kits are about the same cost and include a far more robust Belimo commercial grade motor in place of the old Synchron motor. Both Belimo kits carry a 5 year warranty and will far outperform the original motor. Check them out below:

Use the LMB Kit 4 (three wire upgrade) 

or TFB Kit 4 (uses the two original wires) 

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