NuTone Central vac won't turn off

Central vacs use a really simple low voltage system, two wires, and shorting them together lifts the relay and starts the motor.

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Have you checked the hose for clogs or leaks. Clogged and leaky hoses are an area of concern with any central vac. Unless you hose has a hose sock, then wear and tear from constant rubbing on floors and other surfaces will result in holes and cracks. Pulling the hose can also result in leaks where the hose attaches to the handle and intake connector.
Mix some dish soap with water.
Use shop vac to blow air through hose, with other end capped or "clogged".
Apply soap solution to each end of hose.
If bubbles form, this indicates leakage. Hose will need to be replaced.

Some units have an on/off switch on the power unit itself. Check to make sure that is not turned on. Unplug your power unit and remove the 2 low voltage wires (not the power cord itself) . The low voltage wires start at the unit and run throught your home and attach to each hose inlet. They are usually attached to the unit by simple wire terminals or wire capped to small wires coming out. Just unlug the terminals or unscrew the wire caps and pull the connections apart. Plug your machine back in. If it still comes on the problem is the relay or circuit board/switch/ relay assembly inside the unit. If it doesn't come on with the low voltage wires unattached then you may have two wires touching somewhere in the low voltage wiring.

You have a defective internal relay on the vac. Check for warranty coverage as this is a common occurrence on these big box store units.
If beyond warranty the relay should be a straight forward unit, miniature circuit board type plug in device. Find a Broan Nutone service center or take to vac pro shop for parts.

Disconnect the thin low voltage wiring between the vac and the rest of the house. If the vac continues to run you have a defective relay in the vac motor housing.
If the vac stops you have a short in the wiring in the house, likely behind an inlet in the wall.
If any inlets have been disturbed for painting or renos lately that would be the first spot to look in the house for a problem. Look for wires behind the inlet valve which are touching against each other or a mounting screw or against a metal mounting plate behind the inlet. Start at the last inlet used. Be careful not to loose the spring under the screws where the wiring attaches to the inlets

your problem is incide the vaccum some object is stock , and the blower is cut.

Start with this. Unplug the vac to shut off, then disconnect the low voltage wiring at the vac.Plug the vac back in. If the vac still runs you have an internal short on the relay or wiring inside the vac.
If the vac stops then the vac and final wiring is OK and the problem is in the wiring in the house.
Have you removed any inlets for painting or had any renos done or pictures hung. If so undo what you did last. If inlets were disturbed remove them and look for low voltage vac wires touching metal backing plates in the wall or touching the inlet mounting screws.
If you have done a reno or hung pictures you may have pierece the wire for the vac creating a low voltage short which will keep the vac running until removed. I have seen this happen with freshly installed 1/4 round molding along a baseboard

Dear lord, that is the most absurd thing I've ever heard. Who installed the Vac and DW or were they both in the home before your time?

Normally, if liquid drips out of a CV outlet it's because it was sucked up during vacuuming. However, if your vacuum runs or has suction at the outlets due to the dishwasher running, you have a low voltage gap being bridged by either the dishwasher's wiring or by liquid leaking from it onto the CV wiring somewhere.

Bottom line, you have MAJOR issues inside your home with one or both of the systems, and if there's liquid, there's a dishwasher to be worried about! Look below it for leaks into the basement/lower floor; follow the plumbing (especially the drain waste runs) and figure out where the damage is before your house suffers the lot.

Try to plug the hose in sideways. So the top of the hose is rotated 90 degrees. If the unit turns on then there is something wrong with the hose. It might be a short or it could be a bad switch on the handle. If the unit still wont turn on I would think that maybe the low voltage wire got disconnected from the unit or there is a break in the low voltage wire somewhere along the way. Let me know if you plugging the hose in sideways works.

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Generic problem for all Vacuums
I have a 3 year
posted by patfitz on May 03, 2008
I have a 3 year old NuTone CV 353W central vac system and recently the switch on the hose handle does not turn the system on from any outlet in the house. I have to plug the hose into the outlet and then turn the unit on from the switch on the canister. Any help would be greatly appreciated. Thanks

Hello,
I would advise you to ALWAYS to FIRST UNPLUG YOUR VACUUM before beginning any service procedure. There are a couple of things that come to mind, 1st. you may have a bad switch in the hose and in most cases that can be repaired – if not you would have to purchase a new vacuum hose. 2nd. You may have a bad inlet valve in your hose and most of them are low volt of which would only cost less than $10.00 and can be replaced yourself unless you have what they call a SuperValve of which has 2 low volt wires and then it is wired to your home electricity and that should be replaced by an licensed electrician. It is a low volt and high volt inlet.
#3. the last thing you may check id that you may have a bad relay in the canister itself. Because you should be able to turn on the Central Vac with the switch on the hose and everything should work just fine . feel free to contact your local vacuum cleaner dealer in your area of call the Nutone Factory cust serv line for further assistance. So if you need further assistance, please feel free to contact your local vacuum cleaner dealer in your area or in the yellow pages, or contact the factory phone number or website to further assist you with your questions.
http://nutone.com/ Customer Service
Nutone Inc.
9825 Kenwood Road
Suite #301
Cincinnati, OH 45242
Customer Service 1-888-336-3948
Technical Support 1-888-336-6151
Thanks, Don the Vac Man
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