Pulling Wire Through a Central Vacuum System?

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?

Comments

I'm trying to do this, too...

[Rude Turnip]

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!!!!

tips & tricks

[digitalmuse]

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.