If you’re tired of dragging a portable vacuum cleaner from room to room, you might consider a central vacuum system. Central vacs are convenient, quiet and up to five times more powerful than portable vacs. With self-cleaning microfilters, they capture smaller particles than many portable units, and you can vent the dusty exhaust air outdoors or through a garage space.
While the systems are generally sold installed, you’ll save money by doing the work yourself—with components and materials running between $800 and $1500, you’re not far from the price of an expensive portable model. For our home, we chose a Beam Serenity Series Model 2100 central cleaning system (c. 2001, ours ran about $900, uninstalled, Beam Industries, P.O. Box 788, Webster City, IA 50595; www.beamvac.com). A central vac system consists of a motorized pump and canister, wall and floor outlets, low-voltage cable, thinwall PVC pipe and fittings, plus a hose kit and beater bar. There are a wide variety of accessories available, but these are the basic components.
You’ll find two systems for powering the beater bar motor. Both types have wiring molded into the hose—a 120-volt line for the beater bar and a low-voltage line for the remote control of the central vacuum’s motor. The first alternative has a direct-connect inlet cuff (the fitting that connects to the wall inlet) that taps both low-voltage and 120-volt power as soon as you plug in the hose. This system requires wall inlets to be wired with 120-volt current. The other system has an inlet hose and fitting that handle the low-voltage connection, but the hose has an 8-ft. pigtail that draws 120-volt current from a nearby wall receptacle.
Direct-connect systems are more common in new homes because it’s easier to run the 120-volt lines during construction. In retrofits like ours, it’s easier to install the vacuum inlets near existing receptacles and plug the beater bar into one of those. In both cases, the vacuum’s motor and the beater bar are controlled by a switch on the hose grip.
This project was originally published in the September 2001 issue of Popular Mechanics. You can find more great projects at Popular Mechanics DIY Central.
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Step 1: System Planning
The hose for our central vac is 30 ft. long, plus 3 ft. for the extension wands. Use a 30-ft. string to simulate the hose when deciding inlet placement. To reach all four corners of our 1500-sq.-ft. ranch we needed two inlets upstairs and two in the finished basement. In our case, we could reach three of the inlet locations from a basement utility room next to the garage. This allowed us to place the canister in the garage, while accessing the remaining upstairs inlet from the attic.
Other options include placing the vac canister in the basement, or in a main-floor closet and venting the exhaust through an outside wall. In a two-story home, you might reach top-floor inlets by running pipe through a clothes chute, plumbing chase or interior closet.
The trickiest part of this job is cutting into walls that may already contain cables, fire blocks, ductwork, insulation or plumbing. To avoid insulation, limit your work to interior walls, and use vent grills and electrical outlets as clues to obstacles the wall may contain.
Use an electronic stud sensor to find the space between studs, and then move the sensor up and down to check for horizontal fire blocking. When working from the basement, you’ll need only about a foot of clear space above the floor.
When you’ve located an empty stud space, mark its center and bore into the floor next to the wall with a long 1⁄4-in. bit (Photo 1). Leave the bit in the floor as a marker. Break the nailing flange from a plastic mounting bracket and hold the bracket against the wall, about 12 in. above the drill bit. Trace around the bracket’s flange with a pencil (Photo 2), and then cut the opening with a drywall saw.
In the basement, use the long drill bit in the floor to find the center of the wall above. Bore up into the wall with a 21⁄4-in. self-feeding bit (Photo 3). Then, feed low-voltage cable through the wall opening and into the basement (Photo 4).
A dual ell is a special, short-radius, 90˚ elbow that fits inside a 4-in. wall. Glue one of these ells to the mounting bracket, with the open end of the ell facing downward. Pull the low-voltage cable through the mounting bracket, strip about 3⁄4 in. of insulation from each wire and bind the wires under the inlet’s terminal screws (Photo 5). Tip the bracket into the opening and pull its top and bottom flange against the wall. Reach through the opening of the inlet cover with an index finger and grip the inner surface of the ell. Carefully push the male end of the inlet through the bracket’s O-ring seal and screw the inlet to the bracket (Photo 6). Stop when the inlet is snug against the wall.
Step 3: Run Pipe
With an inlet wired and secured firmly in the wall, cut a length of pipe to feed up from the basement. File away any burrs left by the saw, and coat the leading 1 in. of pipe with PVC cement. Carefully feed the pipe into the wall and twist it one quarter turn into the inlet’s ell (Photo 1).
Install the remaining inlets that have basement connections and join all pipes with sweep tees on the way to the garage. At each intersection of pipe, bring the low-voltage wires together and join them with twist connectors (Photo 2). Fold the wires together and tape them to the pipe. Secure the pipe to the basement ceiling joists about every 3 ft. with the provided plastic straps (Photo 3), and extend the pipe and low-voltage wire into the garage.
To run an inlet pipe from the attic, first use the stud sensor to find the center of a wall cavity. Use a piece of coat-hanger wire to bore through the ceiling drywall, and leave the wire in place as a marker.
In the attic, locate the wire and remove all insulation from the area. Bore through the wall’s double top plate with the self-feeding bit (Photo 4), and use a flashlight to check the space for obstructions. Feed low-voltage cable into the opening from above, and then return to the main floor and cut an inlet into the wall. With the inlet’s ell facing up, apply glue to the end of the pipe and feed it into the wall from above (Photo 5). If a low roof leaves too little clearance for a long pipe, splice shorter pieces together with couplings.
Run the attic pipe to the garage ceiling, securing it every 4 to 6 ft., and tape low-voltage cable to the pipe at least as often. Before replacing the insulation, prevent drafts by injecting minimum-expanding foam around the pipe where it passes through the plate.
Step 4: Mount & Connect Cannister
Bring the attic piping into the garage by cutting a hole in the ceiling drywall (Photo 1). Choose a convenient location for the canister and screw the unit’s mounting plate to the wall. Settle the canister onto its clips (Photo 2) and check it for level.
Join the line from the basement and the line from the attic with a sweep tee, just above the canister (Photo 3). Next, extend a length of pipe to meet the canister’s inlet and make the final connection with a hose clamp (Photo 4). Install the
exhaust muffler on the canister with a second clamp, and attach the low-voltage wires with push-on connectors. Finish by installing a plastic cover over the connectors.