Motors, Filters, and Maintenance for DuoVac Central Vacuum
All Products for DuoVac
Only hear a "click" when trying to start the system? Does it shut off and start back up in a few minutes? These are common signs of a dead motor which only leaves two options. Replace the motor or the replace unit. If you liked the amount of suction it originally had, then replace the motor. If you'd like stronger suction or if you'd like a cleaner disposal system consider a different unit or alternative brand.

How is a central vacuum maintained? Generally, the only thing required is emptying the main unit. Beyond that there are some upkeep and preventative options given below.
Replacement Chart for DuoVac Vacuum Motors, Filtration, & More
Duo-Vac Model # Replacement Motor Filtration
Duo-Vac 1600, 1300, 1350, 1650
120 volt		 Price / Details /
Instructions
119412 (replaces 116392)		 DuoVac's are
mainly cloth filtered.
Duo-Vac 100
120 volt		 Price / Details /
Instructions
116429
Duo-Vac 200, 3230, 3500
120 volt
Price / Details /
Instructions
116765
Duo-Vac 225, 3520, 3525
220-240 volt
Price / Details /
Instructions
117123
Duo-Vac 800, 850, 1404
120 volt
Price / Details /
Instructions
116472
Duo-Vac 820, 825, 1320, 1325,1620, 1625, 2414
120 volt		 Price / Details /
Instructions
116213 (replaces 117275)
Duo-Vac 1530, 2700, 2750
120 volt		 Price / Details /
Instructions
117500
Duo-Vac 2525, 2562, 2720, 2725, 4025
220-240 volt		 Price / Details /
Instructions
117502 (replaces 117501)
Duo-Vac 3220, 3275
220-240 volt		 Price / Details /
Instructions
116355 (replaces 117275)
Duo-Vac 5025
220-240 volt		 Not available from MD Vac
Duo-Vac 125
220-240 volt		 Not available from MD Vac
Basic Maintenance for DuoVac Vacuum

Filtration Maintenance
Much like a regular portable vacuum, the basic maintenance of a DuoVac Central Vacuum System is changing the bag, or, in most cases, emptying the dirt receptacle on the main unit. To do this, remove the base of the unit with a twist or by unlatching, then dump the debris. Place a plastic trash bag over the bottom of the unit. Reach up and grab the center weighted cloth filter and shake it. This filter can be further cleaned or replaced. To remove the filter, grab a side of it and pull toward the center. The outer stiff rim of the filter bends in and the filter drops out. To test filter efficiency, remove it, install the base back on the unit and test the suction. If the suction is significantly better without the filter, then replace the filter. To further clean the filter, wash it and thoroughly air dry it before installing.

Motor and Vacuum Maintenance
There is nothing to lube or oil in or on the central vacuum system, including the DuoVac motor, DuoVac vacuum motor unit, or DuoVac vacuum cleaner. For the indoor vacuum brush, the fibers that get wrapped around the brush roll of the vacuum cleaner head should be cut out and removed on a regular basis.

Pipe and Hose Maintenance
We recommend cleaning out the hose and piping system at least once per year. The best way to do that is with Tornado Central Vacuum Maintenance Cloths. They do a couple of things. First, they push through the pipes, bringing along stalled out debris. Second, they deodorize the hose, pipes, and unit. Some amazing results can come from this product. The vacuum hose will last longer if it is stored on a hanger, always being detached from the vacuum after each use. See if any of these Storage Items can help your situation (scroll to the bottom of the Accessory Page).

Email Reminders to Empty Vacuum
Sign up for the Free Quarterly Email Reminders to dispose of your central vacuum debris. Let the trash build up can reduce suction, making the unit run hotter and clean less efficiently.

Replacement Motors and Parts for DuoVac Vacuums

Troubleshooting
Self diagnose your system using this Interactive Troubleshooting Guide and Solutions.

Motor Replacement
Contact a local dealer for service, or consider doing it yourself. Motors on the DuoVac vacuum have a few fasteners and wires that need to be unattached, the reattached on the new motor. It should take less than one hour. First, turn off the circuit breaker or unplug the central vacuum unit. Then, access the motor by releasing the outer housing. Use the chart to find the right replacement motor for your DuoVac motor model. A motor may have many numbers on it but typically the real motor number starts with 11. Here are detailed DuoVac Motor Replacement Instructions.

Circuit Board, Relay, Transformer, MiniBreaker
Separate transformers, relays, and minibreakers are not available here for DuoVac. However, when a circuit board is installed, the most common board replacement for DuoVac vacuums is the Vacuum Motor Circuit Board for Single Motor Units 110 Volt. The board is strong, yet generic and may need to be retrofitted. There are other Generic Circuit Boards here for units with different voltage and two motors. These robust generic boards are made by the leading industry supplier. An electrician will be able to replace the circuit board, or replace the relay, transformer, and minibreakers with a circuit board quite easily. Print and use the large photograph of the board as the wiring guide.

Motor Carbon Brush
The DuoVac motor has two carbon brushes that wear down and can be replaced before they damage the motor. However, the DuoVac motor may go bad for other reasons while the carbon brushes remain fine. DuoVac motor brushes can be checked every few years and replaced if the 3/4-inch-long solid carbon is worn down. Definitely replace if one or both are down to 3/16 inch. Type the motor replacement number (not model number) in the search box and the motor brushes will come up along with instructions.
 
Note: DuoVac Vacuum is a registered trademark of DuoVac, not M.D. Manufacturing, Inc. Products sold by M.D. Manufacturing, Inc. are not from DuoVac Vacuum but are designed to complement a DuoVac Central Vacuum. Therefore, parts and products carry warranties from MD Manufacturing and not DuoVac Vacuum and thus may alter the warranty provided by DuoVac Vacuum.
Need more help? Try our extensive and helpful DuoVac Vacuum Questions and Answers or give us a call at 1-800-997-2278 M-Th 7 a.m. to 5 p.m. Pacific Standard Time.