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DynaVac Central Vacuum Q&A

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Questions & Answers

Rebuilt Motor - Loss Of Suction

My built in dynavac has lost suction. Motor has been rebuilt. What else could be the problem? Thank you, Marian from Midland Canada

Please make sure you clean and clear the cloth bag in your Dynavac system. Place a plastic trash bag over the bottom of the unit. Reach up and grab the center weighted cloth filter and shake it. 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. If the low suction continues, it’s possible that you may have a clog somewhere in the pipeline. To flush out a possible clog, please complete the following procedure. Plug in your hose to the inlet nearest your central vacuum cannister. Place your hand over the end of the hose for a few moments to build up pressure behind your hand, and then release your hand. Repeat this process for roughly 10 minutes. Once this is completed, repeat the process at the next inlet in your home. Continue this process until all the inlets have been completed. This should help remove any clogs that might be in your system. You can find more help on solution #3 on this page

No Vacuum Power

Was vacuuming and turned off.. then went to turn on again and all of a sudden no power! However the central unit shows power. Tried a different wall plug and still no power. What could this be?

Please use this guide to find the issue and solution, then let us know if you need more help

Replace Power Head and Floor Tool

I have a D100 Model Vacuum which is 10 plus years old. I need to replace the power head. Which power head would be suitable? I would also like a hard wood floor attachment. Wanda Rommens Brooks, Alberta

Please send us a photo of the brush and vacuum hose so we can see what is compatible. We will give you all your options. Thank you.

Dyna Vac Replacement Bags

I have a Dynavac central vac. It is new (6 months) It is located in the garage and I have a lot of dirt and dust from it. Is there a filter or muffler or something I can put on it? Thanks Jan

The filter bag may not installed correctly, or not at all. Replacement bags can be found here,

C-1213-D Bag?

I have an old mastercraft dynavac model 1300, with replacement bag part # C-1213-D. I need bags, please suggest an alternative bag, as I can't find this model on the internet. Could Part # 723MF-5 work? Colin, Mississauga

Yes, you can use the the 723MF-5 if the opening is near the top on your old bags. That is all that really matters, honestly.

Replacing Wall Inlets

Pat-Wallkill I have an old dynavac and need to change wall plates and end hose to update the system. The dia. of hex is 1 5/8 in point to point and 1 3/8 between points,wall plate # 2753. What do I need, to upgrade the system?

Actually the backing plate diameter is the key. Your inlets are not available but if you read the text at the top of this page you'll be able to determine if you can replace the wall plates. The new hose end you can use is here, the Hose Cuff with Metal Ring All our hoses and kits are compatible with the new basic inlets (if they fit your backing plate).

DynoVac D-100 Motor

I am looking for a replacement motor for a Dynovac central vacuum cleaner model D-100.Do yoy have anything that will fit?

We do carry a replacement motor for your system. It can be found here,,220,how2mtr&title=Motor+for+Dynovac+D100,+D150

Replacement Bags

In search of replacement bags for Dynavac home central vac canister: MicroLiner #4465

Hello, you can use either of these bags. They both attach and filter as required. The blue one does a better job as it is made of better material.,723MF-5. Don't forget to checkout all our accessories as well. They all fit your system.

Hexagon Inlets

My mother wants to replace the wall covers for her Dyna Vac central system installed in 1970. However, the inside is a hexagon shape and not a circle shape. I see they don't make these anymore and I need to replace them with comparable. Back of wall plate is marked C2753 and cover with round lift door measures 5 5/8" x 3 1/4". Hole diameter is 1 13/16" point to point and 1 5/8" diam midway between points of hexagon of the flush wall plate. Also need new hoses and power head for carpets. What will work for her.

There may still be a dealer or manufacturer in Canada who has these. You need the same one we think, but maybe someone else knows better. Please look up Johnny Vac and ask them.

2inch DynaVac MasterCraft Vacuum Inlets

I have a Dynavac with hexagon shaped inlet vacuum ports that 2". The vacuum inlet says Master-Craft on them and they fit into 2" connections. What are my options?

Hello, these are really non-standard. If there is any way to repipe the home that may work out the best. There maybe reducers to get the larger pipe down to 2 OD central vacuum pipe. Then you can use a standard backing plate (#517) and Basic Inlet Valve, and then any hose you would like on this website.

Hex Inlet Shape

I want to replace my wall covers for my Dyna Vac central system. However the inside is a hexagon shape and not a circle shape. Do they make inlet valves with hexagon shape anymore? And if not, what can I do to replace these covers. I do not use the system and want to cover the holes. The flat face plates are not big enough. My old cover is 5 5/8" x 3 1/4" and the number inside the back is C 2754. Thank you.

If the our Basic Inlets will fit into the hex hole (a 1-5/8 diameter circle) then you can them and a trim plate (on the Basic Inlet page). The trim plate is plenty large enough to cover your old footprint.