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Pulling Wire Through a Central Vacuum System? 47

call -151 asks: "A friend of mine has a nonworking central vacuum system in her house and I was offering to help her use the tubing as conduits and pull cable to distribute her network throughout the place. Has anyone done this and have any advice to offer? It should go smoothly but I'm sure there are some things I'm not thinking about." Of course, not everone can expect to have a CVS (pun intended) in their own home, but this was just odd enough where it deserved a post. Anyone have any URLs that describe exactly what a Central Vacuum System is, and how it worked?
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Pulling Wire Through a Central Vacuum System?

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  • A link (Score:2, Interesting)

    by JediTrainer ( 314273 )
    This article [] has some information about techniques used to INSTALL vacuum systems. It might give you an idea of how the thing might have been built if it was done correctly.
  • some advice. (Score:2, Informative)

    by laymil ( 14940 )
    ok...this may seem simplistic, but keep in mind the SIMPLE things when doing the wiring.

    Whenever possible try to go down through the makes life easier.

    For long horizontal stretches, slingshots can be your best friend. (sounds stupid, but it works)

    A lot of your problems will depend on the width of the try to run the wire all at once in bundles to make life easier.

    That's all i've got for now. peace.
    • For long horizontal stretches, slingshots can be your best friend. (sounds stupid, but it works)

      The best thing to use when pulling cable is to tie a pull string to the end of some fish tape []. Then, pull your cable back through using the pull string.

      Fish tape rocks. It works great for long, straight pulls and tight U-turns... and everything in between.

    • Slingshot's work pretty well with a washer secured to a string, but I've had a lot of luck with a mini-crossbow (which may be illegal in your state... sorry if that's the case) mini-Crossbows may be a bit wider than your standard fare slingshot, though.
  • I'd have serious concerns about using a central vacuum system as conduits for CAT5. Your network performance is going to suck...

    Sorry, I could resist...

    • Well actually, depending on the direction of network traffic at any given moment; The performance may suck, blow - or to the amazement of Bart Simpson, it may both suck and blow at the same time.


  • Run extra cable (Score:3, Informative)

    by dustpuppy ( 5260 ) on Wednesday October 03, 2001 @09:03PM (#2386496)
    I'd run extra cable while you're doing it because it's a lot easier running a bundle of cables along a narrow conduit than it is to feed an individual cable through a narror conduit already filled with other cables.
    • You Sir, are correct. If call-151's friend doesn't already have coax cable run throughout the house this is most certainly the time and place to do it. In my semi-limited experience, a zip tie every several feet helps greatly when running multiple cables at the same time.

      On a side note, I did at one time rent a house with a central vacuum system, and with the system came copious quantities of coiled vacuum hose (well, three 20' lengths anyways) and many assorted attachments. If you wanted to make your rack/router/servers/main wire collection point look snappy, you could attach an extension hose to the wall socket and run it to the wire's destination and run the wires though the extension hose. I have also seen CLEAR hoses for sale as well...

    • Or just run a length of string alongside it. That way when you feel the need to run more cable, just put together your new bundle (along with another length of string), attach it to one end, and pull through. You've now got your new cables in, plus another string ready to pull through more when the time comes. Plus you're not paying for cable to sit unused in the tubing.
  • by Rude Turnip ( 49495 ) <[valuation] [at] []> on Wednesday October 03, 2001 @09:50PM (#2386616)
    My mom's house has a central vacuum system, too. We've never used it in the 25 years that we've had the house, so the dust puppies living in its tubes must be ancient! Before my mom sells the house and moves, I'd like to run some CAT5 through the tubes and set up some keystone jacks in place of the current vacuum sockets. Then the realtor can say that the house is "wired for broadband internet and home networking." Should add a dollar or two to the market value :)

    For the unitiated, this is what a central vacuum system is all about:

    Imagine the telephone wiring in your house. Now imagine dirt, dust and tiny bits of garbage going through those wires and getting sucked into that little junction box in your basement. That is the jist of a central vacuum system.

    In the basement there is essentially a cannister vacuum attached to the wall. However, the motor is more powerful and there is a 2-3 inch diameter tube going from the top of the cannister into the floors and walls above. In certain rooms, there are vacuum jacks just like phone jacks, but wider of course. To use the vacuum, you insert a long, flexible tube into the jack. The end of the tube that goes into the jack is metallic and connects two metal contacts in the jack to turn on the power for the cannister in the basement. It's just like using the tube extension on a regular upright vacuum cleaner.

    I have 1000 feet of CAT5 on standby. All I have to do now is find the time to do this and also learn how to wire CAT5 into jacks. My words of advice are this:

    1. Make sure the tubes are relatively clear of debris. I've shone a flashlight into my vacuum cleaner tubes and the amount of stuff that rests on the bottom of horizontal runs of tubes is amazing.

    2. Check the local building codes to see whether or not plenum cable is required for a residence. It's sure required for offices around here. Plenum costs more, but it doesn't get smokey and toxic like regular cable in case of a fire.

    3. Unless your tubing is really complicated, you should have access to the actual tubes in certain parts of the house (basement ceiling, inside certain closets). If the tube is visible in certain places and then it bends up into the walls, feel free to cut yourself a little porthole into the tube to help fish the CAT5 through. Note: Make sure you follow tip #1 before cutting holes...or wear goggles :)

    4. Think about where a broadband internet connection would be coming into the house. Try to syncronise the location of the hub/switch/firewall/server room with this location.

    Other than that, the rules should be the same as if you're putting wire through any other object and I'll defer to the experts here for that advice. Good luck!!!!
    • by ptomblin ( 1378 ) <> on Wednesday October 03, 2001 @10:39PM (#2386808) Homepage Journal
      Should add a dollar or two to the market value

      I hope you're being facetious.
      I think you'll find there are a lot more home owners out there who want a central vacuum system than a central wiring closet.

      But if there is one thing I've learned over the years, you don't put money into your house to increase the resale value of your house. Anything you add is going to impress one buyer but absolutely turn off another. That's why you see houses with swimming pools filled in or outbuildings bulldozed as soon as they change owners.

      The only money you can put in your house that makes a difference to the resale value is stuff that prevents the price from going down. This is a hard distinction to make. Replacing the roof when it's getting bad is an example of something that will prevent the resale price from going down.

      • My thought is that if someone doesn't care that the house is now wired, then they'll just ignore the cabling and that will be ok. However, it may spark some interest compared to other, identical houses on the street. The vacuum system itself is not that great given the jack layout and newer parts of the house don't even have jacks; so the tubes are essentially wasted for practical vacuuming purposes.

        There are only four vacuum jacks and the plug-in tubes cannot reach/are too cumbersome to vacuum every part of the house like a regular vacuum can. And forget about the tubes reaching the family room, which was added years after the vacuum tubes were installed. It is possible, however, to wire the family room since the tubes are at least in proximity and a rogue line can be strung out there if need be.
        • i was going to say, just fix the CVS as it would be a snap and you could get a new vacuum on the "cheap". But if it is poorly installed anyway, and you can get the cable install done super cheap and easy then i say go for it. That way you have some operable cable and jacks, rather than barely usable vacuum. But remember throwing money into a house right before it's sold will NOT up the resale value proportionately. just like a car.
          now that i think about it, the prospective buyers prolly won't notice that the CVS sucks (not very well) so i return to my advise to fix the vacuum system.
          best of luck!
          • Yes, we could get a new cannister/motor installed in the basement, but the vacuum jacks are only in certain parts of the house. Even in the reachable parts of the house, using the flexible hose is a pain the further you get from the jack because it always bumps into knick-knacks and stuff. CVS is just a clumsy, "gee-whiz" idea leftover from an earlier time.
        • Have your mom make a yarn pom-pom you know like on the tip of those dorky home-made knit hats, it should be a sized a little less than a stuffed fit in the vacuume tubes, tie the cat 5 to it and suck it thru with a working vacuumme cleaner. neat and easy way to run the cable!
          BTW the first cent vac I know of was in Fairlane manor build by Henery Ford. the place was also wired for DC electricity because Thomas Edison said it was better, less fatigue failure of the light bulb fillaments!
      • Presumably if done right, you can have both. If the CAT5 exits the vacuum tubes before the end (both the vacuum cylinder and wall ends) through some sort of seal (blob of caulk at a pinch), then there is still a vacuum, and CAT5.

        I doubt having a wire running inside the hose would impede airflow too much.
  • by NevarMore ( 248971 ) on Wednesday October 03, 2001 @10:10PM (#2386703) Homepage Journal
    Ok this is a bit off the wall, its for the tinkerers.

    Run your cat5 thru the pipes, have it all exit to the side of the main pipe. Seal this hole airtight. Now connect a hose to the back end of your computers near the jacks, remove the case fans, and add a filter to the fan holes. Now youve got centralized computer air cooling.

    Keep in mind ive never used one of these so, im kind of assuming that these CVS systems are quieter at the ends than a pair of 80mm fans.
    • Excellent concept!! Unfortunately the central vacumm system I once had was LOUD. In fact, it sounded suspiciously like someone was running a vacuum in the other room! I forget the name of the manufacturer or model, but it was a 4hp electric motor that plugged into 240V. At any rate...
      #1 It is LOUD
      #2 It would probably suck (heh heh) electricity like a madman. (newer models are likely more efficient)
      #2 I suspect these unit are NOT designed to stand up to the stress of constant running, or even running for extended periods.

      But, in the spirit of your above comment, I would like to hear if anyone has had any luck with some sort of central cooling system for multiple computers.

    • Do you realize that this might set a whole new trend in overclocking? I can see it now. Those OC geeks are going to hook a massive cooler to their computers and have it exhaust the heat out of the CVS pipes. This could be a riot.

      "Overclocking equiped house."
  • by unitron ( 5733 ) on Wednesday October 03, 2001 @10:36PM (#2386799) Homepage Journal
    You'll need to do some research to see if the vacuum system's tubing is acceptable under your local building codes for running low voltage cable through (*Do Not*, under any circumstances, use it for any sort of power wiring, i.e., 120 V AC). If you don't do a legal install and have a fire of any cause later, you may well have given your insurance company grounds to dismiss your claim.

    As with woodshop sawdust collection systems, a central vacuum system should have a bare grounding wire already installed in all the pipes to prevent the rush of air through the plastic from generating enough static electricity to cause a spark that could ignite flammable dust and cause an explosion. Probably best to leave it intact.

    Assuming that the local building inspector gives you the go ahead (or if you're planning on some other installation elsewhere using "real" conduit), here are a few tips.

    Always install a pull rope of some sort so that you can install more cable later or pull the old stuff for reconfiguring.

    You can use a vacuum cleaner to pull the pull rope through the conduit in many cases (attach something a little smaller than the conduit inner diameter for the vacuum to pull on to one end of the pull rope), then attach another pull rope and the cable bundle to the far end.

    Sometimes you'll need a small gauge pull rope to pull another larger one through before you can pull the cable bundle through.

    Insulated 14 gauge copper is flexible enough to be used as the pull rope left in the conduit, and you can get it with insulation that's rated for installing inside conduit. Consult your local building code and inspectors to find out what color insulation will be allowable for a wire connected to nothing at either end except for something (non-conductive) big enough to keep it from falling down into the conduit where you can't get at it.

    14 gauge copper with some sort of smooth ball on the end (a big crimp-on lead fishing weight works well if you smooth off any rough parts) can be used to push through the conduit instead of pulling with a vacuum.

    Electrical supply houses carry a kind of synthetic grease that you can use to lubricate the cable bundle to make it slide through the conduit more easily.

    • Using a vacuum to pull rope is a good idea, but what I found best is nylon string and compressed air . You can push hundreds of feet of nylon string in seconds through hundreds of feet of any size tubing with your portable air tank. Pulling wire couldn't be easier.
      • Yep, that's what the pros do

        In a previous life in utility construction, I saw the grizzled old conduit guys "blow string" with an air compressor. Be sure to use an old wadded up rag at the head of your string, that way it will maintain a maximum head of pressure behind it...

  • by Dios ( 83038 ) on Wednesday October 03, 2001 @11:26PM (#2386920) Homepage
    What about using the vacuum to help run the wire? Tie some light but strong string to a sponge or table top tennis ball that will easily fit through the system. Put ball/string in outlet (tieing the opposite end to something..) Turn the vacuum on.. and when the ball hits the canister turn the vacuum off.. next pull the cat 5 with the string... Seems good in theory.. who knows in practice....

    Should be fun though!
    • A smallish ping-pong ball can get sucked around easily, but there is no way the motor is strong enough to create enough suction to draw CAT5...especially when you consider that the tubes have to make turns at certain points. It would be easier to tie some CAT5 to a hamster, snake or gerbil and let it run around the tubes. There's probably quite a few guys in SF that could help you with this.

      • But it doesn't need to pull the cat 5. Instead, have it pull a light string (fishing line would be great) which could then be used to pull through a heavier string, which could then be used to pull the cable. Pretty slick. Or maybe I sould say pretty sucky.
        • Nylon cord like 1/4" or 3/8" and a ballon with only a little air in it, and a sho[p vac is what we use. Your main problem is stopping the vaccum as the ballon shoots into it. Then pull a permant pull string with the cable bundle, and use big washer or nut to keep the pull cord from being lost.
        • Believe it or not, there is special string made for exactly this purpose - called a "Line Package"

          It's a bobbin of string with a foam rubber end. The string is flat like dental floss, but MUCH stronger.

          You put the bobbin in the conduit, secure the free end and then blow/suck the bobbin to the other end.

          The advantage of this is that you are not pulling the string the whole way, it's just coming off the bobbin

          They then use that string to pull a yellow polypropylene (I think) cord through, and then use that to pull the cable

          You can get all of this (Plus pulling grease) at a good electrical supply house

          Check out:

  • tips & tricks (Score:5, Informative)

    by digitalmuse ( 147154 ) on Wednesday October 03, 2001 @11:37PM (#2386941)
    Having done this once, here are some tips when it comes to the actual installation. However, I provide the following caveats, so take heed:
    A) check with your town/city building inspector - you mentioned that you're doing this to help increase the value of the place when you put it on the market. You do not want someone to buy the place, then sue you for doing non-code work in the place when they burn it to the ground. This is a must. I would personally check with the building inspector and make copies of everything he says is applicable. I believed someone mentioned checking out what kind of line you can leave in the ducts as a pull-guide, again, check with the town.
    B) The system that I worked on had it's own integrated conductor system that used the flip-open facia plates to close(open?) a low-voltage circuit that triggered the main vaccuum in the basement. Once you've gotten all your guide-lines drawn, you should disconnect everything else electrical from the system. Label all the existing connectors, take it off, box it up, and stick it in the attic. When the Luddites move in in a few years, they may value the CVS more than a house-wide network.

    When I helped wire my friends house this way, we took a few lengths of wide cotton sash, and connected them to kite spools. Using them as a primitive chimmney-sweep brushes, we went one port at a time, and fed the rags in, feeding in a few feet of line, and then pulling back in most of it. The doubled-over loose ends along with the plunger action seemed to release a lot of the dust in the narrow ductwork (~2.0" dia.). Check the info on the central vaccuum unit, our's was marked that you should not use it continuosly for more than 20 minutes. Needless to say we took advantage of this to self-medicate ourselves during the scheduled downtime.
    We then repeated this for each branch of the system, cleaning out the collection bucket every couple times. Make sure that you get the entire length of the run, a person by the collection bucket will immediately notice the change in tone when the rag stops blocking he duct work, and starts trashing about in the collector.
    Once this was all finished, we then repeated the process, only this time, we fed the rags and lines down again, this time, we didnt' pull the rags back out to their starting point, instead, we pulled through enough slack to allow us to anchor the lines from each room outside the can. Label these lines, remove the rag, cut off the line outside the top-side vent, label this end as well, then cut it off. repeat with the next vaccuum connector.
    In the end, you'll have a spagetti-farm of labled strings coming out of the collection unit, and your house will be strung like a spider-web in a straw-factory.
    (at this point, we confirmed that all the lines were not snagged, then proceeded to unmount the CVS collector, motor, and the transformer for signal lines.)
    Now all your hard work has paid off, and you are ready to pull the wires. I would suggest starting top-side, no need to fight gravity on this one. Just connect your wire bundles up to the feed strings (along with a new 'safe-to-put-in-the-walls-sez-the-inspector' pull line) and have the guy downstairs start pulling down fresh coppera along with the new guide line.
    As always, go slowly, work with a partner on the other end, and be carefull. Once you've strung the CAT-5 up through the pipe, label and secure the new guide lines, mount you keystone jacks, punch down and test.

    As an added benefit, you can now truly say that your home network used to suck, but not any more.

    Good luck.
    • Oh, I apparently forgot to mention, when you're feed the lines into the vaccuum, the whole process is much easier if the vaccuum is ON... the system sucks, use this to your advantage.
  • Okay, I normally hate reading the posts where someone suggests something totally different from the question being asked, but here I go doing it. Why not configure an 802.11b network for the house? Seems like it would ease the pain of running cable and you wouldn't have to worry about all these other things that have been posted in this thread (like getting a building inspector to sign off on your work). I'm not trying to be a smart ass, just trying to make sure that all options were considered.
  • Don't do it! (Score:3, Informative)

    by ivan256 ( 17499 ) on Thursday October 04, 2001 @09:46AM (#2387931)
    Though it may seem dumb to people like us (geeks), the central vac is probably more apealing to the housewife that is going to be moving in then CAT5 would be. Especially when you consider how cheap 802.11b equipment is, you should leave the central vac. You'll more likely lower the value of the house if you change it into CAT5 conduit.

    Unless it's broken. That's a whole different story.
    • Yeah, my house was built "wireless ready". In fact, so was my whole yard, and way down the street and a whole load of other places, except for the faraday cage room ;-)

      • LOL. Remind me to steal that. The newest real estate agent buzzword--"Wireless Ready". Kind of like all the audio equipment marketed as "Digital Ready" when CDs first came out.
  • I would get a shop vac and hook it up to the old vaccuum location and turn it on. Then I would go around the house and open the vaccuum inlets ( to clear the debris).
    Then get some "pulling string" and tie a piece of cloth to the end and let it go into the tubes, with the vaccuum on (it get's pulled for you) label the ends of the string and secure the "pulled string" do the rest

    Now just attach your cat5/fiber to the strings and pull the string label them and punch em down

    replace the outlets w/jacks and you are done

    -- Tim

  • Common sense and some ingenuity ... for the nerf and air pressure. Many industrial commerical electrical contractors use a method similar to this idea, already. They'll tie a light-weight line to a foam ball and use compressed air to blow it through the conduit in the building, pulling the line through. Then, they tie the wiring to the line and pull that back through to wire circuits.

    The only problem with this method -- is that conduit is 3/4" diameter and thin wall galvanized metal and can take the higher PSI of the compressor but the Central Vacuum Pipe of a home is 1-1/2" PVC, like most sink drains have.

    The vacuum might not generate enough push or pull pressure to snake lines though. Why not run the wire through the wall cavities and fix/replace the central vacuum? Then you'd have both working.

    I'm just a bricklayer

  • I used to have a 24-hour CVS about two blocks from my home, and two friends and I decided that it would be a good idea to wire it up for broadband. (That way, we could check Slashdot while waiting for perscriptions to be filled with our laptops)

    We were going to install our own conduits, but the big problem was that the store manager would not allow us to run CAT 5 from the house through the store.

    We waited until 3am to have our MAN install party. We ran into the store with stockings on our heads and locked the night manager and cashier in the back room. Finally we were free to install our CAT-5.

    Our plan was foiled when we ran across the magazine rack, and began lusting after the glossy's of Natalie Portman in People magazine. We ended up with a "hot grits" problem and before we could realize what was happening, we were arrested by the police. Those fascist cops (paid off by RIAA, no doubt) even started searching our laptops!!

    I ended up in a cell with my friends and this guy who was permamently bent over with a gaping rectum. He kept muttering something about "those goddamn goats"

    I got out on bail, but now I'm the same plight as Dmitry. I'm oppressed by "the man" and need free legal assistance!

    Please help!
  • Was the question for real ? What is central vacuum system ?

    If you really dont know what is cvs, its just what it sounds like. A-hole-in-a-wall-that-sucks. No need for vacuum cleaner, just plug the vacuum hose into the hole and you can clean the room with "central-suck" =))

    Google came up with this site [] explaining things a bit better.

  • I'm considering using the return air ducts to run cat5. They already run to each room, and run past the closet where I plan to terminate everything. Would this be similar to the CVS, or is there anything else to watch out for?

"Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats." -- Howard Aiken