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AstroVac Vacuum Unit Services Q&A

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Questions & Answers

SR-72 Burning Smell and No Power

Hello, I have a SR-72 that suddenly lost suction and started emitting a strong burning electrical smell. The unit was installed in our home in the early 90's. Should i replace the relay, motor, etc? Thanks Craig Beverly, MA

Only the motor will need replacing. At times the minibreaker fails as well but if it didn't pop out then it is fine.

Dealer Locations

Is there a dealer or someone who fixes astrovacs near Pelham AL 35124? Jill Pelham

Use our Dealer Locator found here,

Astrovac SR-36 Clicks But No Power

I just moved into a condo that has an Astrovac SR-36 installed. When the hose is inserted into outlet the motor does not turn but an audible click is heard in the unit. Souns like a relay operating. Is this a relay problem or bad motor. The unit is about 12 years old I think.

With the relay clicking on, and the age of the unit, you most likely have a bad motor.

Astro Vac MK-X Filter Cleaning

I have an Astro-Vac MK-X. How do I change the filter? Thank you.

The filter on the Astro Vac is only a screen that needs to be brushed clean when it gets buildup on it. You can use a small brush, such as a toothbrush, that will remove any debris that may be clogging it.

Astro Vac Model MK-X Filters

I have a astro vac mk-x. problem is it blows out a lot of lint and hair in the atic. does this unit have a filter besides the wire mesh up inside? I dad the unit for 29 years. replaced motor one time. could you please help?

The Astro Vac cyclonic systems only have the mesh filter to stop large objects from entering the motor. If debris is an issue, you may want to consider replacing the unit with a bag-collection system that will provide much higher filtration and keep the lint and hair out of the attic.

MK-X Motor - Which One?

I have an Astro Vac Model MK-X. The motor burnt up.You offer 2 motors for the X, how do I determine which one. thank you

You can tell the difference between the motors in that one has a plastic top, not metal. The plastic top is also taller. You can get the photos and specs here to see which one you have. It is really quite simple to tell but if you need help please let us know over the phone or send in a photo.,207,220,how2mtr

Dirty Machine, No Suction

No suction. Think machine is dirty. Don't know how to clean it.

It may be that the screen is clogged. Remove the bottom and reach up to clean the screen under the motor. If that doesn't help run through this guide

Cleaning Under Motor

Have an AstroVac MK-X model, How do you clean the metal dust screen at the top of the canister underneath the motor other than vacuuming? Is it removable?

The mesh is removable and replaceable with When you motor dies you can replace the entire unit with one that filters a lot better, such as SilentMaster S44 or FloMaster M85. These also have 50% more power. If you have any questions please let us know. Just pull down on it. The metal screen behind it needs to be brushed off.

Terrible Noise

Hi, my SR 38 is making a terrible noise, but works fairly well otherwise. I think the motor is dying, but it appears there are 2 motors to replace? Is this correct, thanks! Richard in Peachtree City, GA

Hi Richard, there is only one motor. Check the minibreaker on the side of the can. There should be one, representing one motor. The motor is going bad so you can replace the motor now to ensure no damage to eletronics when it overheats and finally dies. You can find the motor and instructions here

Installing the Inverted Filter

Astrovac SR-40 I was cleaning the canister and the inverter bag fell, now I dont know how to install the inverted bag, can you help?

Hi, to install the inverted, center weighted, cloth filter flex the stiff outer ring inward. Position it near the indentation and then let it pop back into place.

Mark X Motor

I have a Astro-Vac Mark X installed in 1968 that has stopped running. Does this vacuum have a filter? Could the filter being dirty cause the vacuum to quit running? Does this unit have a reset switch? If the filter could not be the cause for the unit to stop running, would the next remedy be the motor? If so, where will I find the number for the motor.

Here there where two motors used over the years on the Mark X. Both are here,207,220,how2mtr&title=Motor+for+AstroVac+MK-X. The motor is the issue though there is a filter up inside the tank that you reach up and pull down on to remove. The motor sits on the top of the unit and is accessed by removing screws along the motor shell seam and lift it up. There should be a reset button on the side.

Little Suction

Astro-vac little to no suction can u help, thanks Lesley

Hi, please start with this self help guide at

New Motor Stopped

I just purchased and installed the motor for my central vac. and when I placed the hose in the inlet, it operated but then I guess it stopped/burned out. I don't know what the problem is. I figured if I replaced the motor in it's entirety, my problem would be resolved. It began with a constant operation of the motor and sparking. I unplugged the unit and ordered the new motor. Could it be I need to replace other parts like the transformer/relay? I have an astrovac c-42. I'm not even sure the original motor is burned out. Help! Susana

Hi, sometimes the minibreaker pops out. Please check that on the side of the machine. If it pops out again then it needs to be changed. It is rare but when a motor goes bad it can ruin the minibreaker. Use our 10 amp one if it is allow or use #235S circuit board if it is on one.

Replacement Paper Bag

AstroVac - we are looking to buy vacuum bags for AstroVac system, the unit measure 22 inches by 13 inches, please advise which should we buy. Attached are the pictures.


AstroVac vs Beam

I am researching central vacs. I've narrowed down to AstroVac SR-14 and the Beam 375A. Beam is well known and I can find lots of info on Beam but I don't see as much on AstroVac. The AstroVac has more suction power than the Beam but I'm also looking at reliability, and effectiveness (if the accessories are good) not just a powerful motor if the other parts are substandard. Which one should I buy? they are both within a $100 of each other. so the price are comparable.

Hi, since we are also a manufacturer we do have an opinion beyond these two brands. You found us because we have many customers with these other brands who buy our compatible accessory kits because of their durability (such as Stealth and EdgeLift). For the vacuum, we at MD still make ours in the USA with 18 and 20 gauge steel and powder-coated. We also stay on top of technology and have the latest in vacuum motors. We have models with 650 airwatts at 15 amps! One model costs just over $500. Also, we have disposable bags (costs about $15 a year) which are superior to Beam's permanent filter and AstroVac's dirty exhaust through a mesh. Please visit our site or call us for more information!

Gasket for Turbo Nozzle

Hi! There, I have a Astro old model TURBO 110. Everything still works but the rubber ring between the main unit and duct connecting bin is missing. Do you have this part available?

Hello, what you are looking for must be #44516 here


I have an Astrovac central vacuum system but the previous owner of the house left no information on it and the model number is not on the unit. I need bags. Thanks, Rich McRay

Hello Rich, the only bag used was this one Are you sure it used bags though? Many didn't.

Cone Goes Up or Down

How is the cone supposed to be instaled in an Astro vac MK-X? Does the narrow end point down? Phil St. louis

Hello, the narrow section points down.

SR72 Not Working

I have an Astro Vac Sr - 72 which is 19 years old. It was working fine and all of a sudden it is completely dead. No noise, no suction, nothing. I checked the circuit breaker and it appears to be ok. What could be wrong? Deborah, Warren, NJ.

Please go over this chart to find the issue and let us know if you need more help.

Taking Off Motor


Hello, access the other side of the bolt/nut by going in through the other end of the vacuum unit.

Too Much Dust from Unit

Hello, I own a Astro Vac Model C-MK X can I purchase bags for this vacuum as a lot of dust comes out and where it is now I can't vent it outside is there a filter I can put inside on top of the metal screen ? Please advise Tom (Waterloo, Canada)

Hello Tom, you can actually change to a filter bag type of filtration on most Vacumaid units. Follow the directions on the right side of this page

Screen Clogging - Losing Suction

I have an AstroVac that was put in my new home in 1999, recently we emptied the canister below and gave the filter bag a good shake replaced everything back to where it was and now it seems I only use it once and it loses suction. We found the screen gets debris on it after just one use. Do you think the cloth filter bag does not fit properly any longer allowing dust to clog the screen so quickly? Or is there something else we should be looking into? We have always emptied the canister every few months before with no problems. Angela Southington, CT

Hello Angela, sounds like debris is getting around or through the cloth filter. Inspect it for holes and be sure that the last time you shook it that you didn't unseat it around the edges.

User's Manual

I have an AstroVac MK-X. Can you tell me if there is a user manual or installation manual available. I see from other questions that parts are available. Thank you.

Hello, the only difference with the AstroVac and other central vacuums is the filtration. There is only a single filter up under the motor that needs cleaning whenever you empty the bottom bucket (every couple months or so). Other than that, all the documents on our support page apply to your vacuum

How Does Cyclonic Work?

where can i get an explode view of an MK-X unit to find out how this cyclonic system works ?

We don't have a diagram (but you can call for more information). The cyclonic is really simple. The air enters, spins around like a tornado, the plasic cone helping this, the heavier material falls but the really light stuff goes up towards the motor and is sometimes stopped by a filter or screen but most of it goes through the motor and out the exhaust. That is why it should be vented. Be sure to clean the filter or screen way up inside the unit. If you loose suction, look at this first.

No Suction

I have a Astro Vac Model Mark X. It is not working when I open the outlet on any outlets. I have tried bushing the screen and somehow I think I'm not cleaning it well enough. I have used a ordinary bush, but still seems to have a lot of dust. Could this be the problem? Or could it be the motor? Please help Glenda in Louisiana

Regarding the filter screen, shine a light up there and make sure air can get through the screen. Is the motor working? If so put the hose directly to the canister to see if the hose is clogged. If not and you hear a click, you need a new motor. Here is more solutions:

Always On

I have a Astro Vac Md# MK-X installed in 1990-91, my problem is that the vac motor wants to stay running unless you go out and unplug the unit from the electrical outlet. I have checked all the wall outlets to make sure the seal on the cover is working, they appear to all be working. I have checked the relay and from what I know it appears to be ok, I don't know how to test, and don't know how the transformer works with the system. Help please.. Thanks, Troy

You need to isolate the vacuum by detaching the low voltage wire from the canister. Also be sure there is not an on/off switch that is not in the on position. Also use this chart

No / Little Suction at Outlets

I have an old AstroVac model Mark 1. The power unit works fine, but alas the outlets do not. The one by the side of the vac works 100% - all others work from 0 to 50%. Is there anything that I can do to restore power to these outlets.

Since your suction is good at the tank but not at the inlets it means you have a clog. Please use these ideas to fix the problem .

AstroVac SR-60 Bag

I need a filter bag for my Astro Vac model #SR-60. Is the part # 723EF bag the right one to use? If not, can you tell me which bag to order? Help?

Motor Cutting Out

My Astro-Vac Model MK-X cuts off every 2-3 minutes and the button then comes out on the side for us to restart it. We just put in a new motor 5 years ago. What do you think is wrong with it? Or please give me a dealership I can get someone to come look at it. Thanks

Sounds like you need a new motor. If you vacuum your home 3 times a week it is possible to use up a motor in 5 years. The button that pops is heat sensitive and can go bad as well. Please send your zip code and we will help you find a dealer if that is what you would like to do.

Dust from Exhaust

we purchased a home with an Astro-vac MK-x and it seems to make quite alot of dust around the unit whenever we use it. Is there something wrong, or is there something we can do to stop this? Waiting for your response. Thank You, Debbie at


AstroVac cyclonic units used motors with a horn on them. If the horn is sticking out you can exhaust the unit to the outside. Here are the materials you will need.

MK-X Filters?

we purchased a home with an astrovac model mk-x and would like to know if this unit uses a bag or filter in it? and where i may purchase them thank you

We show that the X model was cyclonic. Meaning there is a screen that needs to be brushed off from below. The screen is just below the motor. There are no bags or filters.

Bearing is Grinding?

My Mother-in-law's AstroVac MK-X is making noise like the bearings on the motor are going out. I took it apart to clean it and the entire housing above the white cone was full of dog hair and dust. I have cleaned it out but noticed a loose metal ring between the metal screen and the top of the can beneath the motor. Where should that be placed? I am going to put it back together and run the motor to see if it sounds better, but will probably end up replacing the motor. Any suggestions?

Don't know about the ring but your guess is correct about the motor. After their 800 hours, or so, of use they are finished and need replacing - which is not hard to do. The sound you hear is the bearing going out. Also, you'll need to keep the screen cleaned on a regular basis though so you get good suction and the motor gets enough air.