Can anyone help me with my central vacuum please?

[buco]

Hi guys.

So my central vacuum doesn't want shut off. It's one of those ones that plug in the wall. I have about 6 outlets, this has just started recently.

To turn the vacuum on and off I have to pull the power cord or else it won't shut off.

Can anyone help me out so my wife doesn't think I'm a useless ****.

Thanks so much.

 

[buco]

Here's a pic of the outlet. Sorry about it being upside down.

 

[gpalmer77]

Assuming you have the system wired correctly whereby you have thermostat-type wiring going to each inlet, you likely have a short in the wiring somewhere, or a short at the inlet terminal itself. I'd pull the inlets and inspect the wiring at each one, then check at the vacuum end or where the wires tie together on the way back to the vacuum unit.

Did you do any DIY near any of the piping recently? Something that might have hit the wiring and shorted it out?

 

[RickP]

I would try to isolate the fault first -- is it in the house wiring or in the central vac unit itself? Try to disconnect the house wiring from the central unit and turn it on/off with the switch on the unit. If that fixes the problem, then the fault is in the wiring -- probably a short at one of the outlets. Just remove each outlet and look for frayed wires -- if you don't see any, try leaving them all disconnected. Then connect them each one at a time.

 

[Milton Shaw]

Unplug the low voltage at the unit to make sure it's in the wiring instead of just a bad relay in the unit itself. Should be a plug with two wires on it somewhere around 20 gauge wire at about 24 volts. Then if the unit turns off you know it's in the wiring instead. Check it where it junctions together, unhooking it all an then hooking up one pair at a time until the unit starts and you know that circuit is shorted

 

[porschedude996TT]

The easy thing to check is to look for some foreign object is bridging the contacts at each inlet. Then determine if the wiring or the vacuum motor is at fault. If it runs with the wires removed from the motor, it is inside the motor. If is doen't run with the wires disconnected, I would then remove each outlet and look at the wiring. Your looking for the two wires that bridged together.

 

[buco]

Thanks guys.

First thing I will do is disconnect the vacuum from the outlets and see if it runs.

Then I'll check the wiring and clean the outlets.

I haven't done any renovations before all this.

Thanks again guys.


Will update.

 

[buco]

Ok so I pulled these 2 wires and plugged in the vacuum and the vacuum ran. Does this mean its the vacuum itself?

I can't see any other wires going into it.

Thanks guys.

 

[buco]

No made in Canada jokes

 

[RickP]

It sounds like the relay is bad inside the vacuum itself, or else there's a short in the low voltage wire inside the vacuum.

Here's a good troubleshooting guide.

 

[buco]

I should mention that when I disconnected those 2 wires I can turn the vacuum on and off manually at the vacuum.

Time to start checking the inlets?

 

[buco]

It sounds like the relay is bad inside the vacuum itself, or else there's a short in the low voltage wire inside the vacuum.

Thanks Rick.

Did you read my last post? Is what you said still true then if it turns on and off at the vacuum itself with those two little wires disconnected?

I should also mention that when the vacuum is running with the 2 wires connected it won't turn off with the switch but has to be unplugged.

 

[RickP]

Okay, it looks like you posted right after me. If the vacuum works normally without those wires attached, then the problem is in your house wiring. Try using a screwdriver to connect the two low voltage wire terminals (if you can tell which ones those are). You could use a voltmeter to make sure there's 24V between those terminals before you connect them together.

If the vacuum works normally by connecting those two wires, then you can be sure the problem is in your house wiring.

 

[pop pop]

Not to step on Rick, but inside the cannister you'll find a relay, transformer and the motor. Your relay is likely stuck/points welded closed. This relay is opend and closed with a signal from the small wires you unplugged. Since the small wires had no affect on your problem, the relay must be remaining closed allowing current to the motor. Relays are readily available as mine uses a common relay used in HVAC service.

 

[RickP]

No problem at all. The more help the better!

My thought was that if the vacuum worked correctly with no low voltage wires attached, that the relay was probably good. But that troubleshooting guide (post #10) has a more detailed list of steps to diagnose it.

 

[gpalmer77]

Not to step on Rick, but inside the cannister you'll find a relay, transformer and the motor. Your relay is likely stuck/points welded closed. This relay is opend and closed with a signal from the small wires you unplugged. Since the small wires had no affect on your problem, the relay must be remaining closed allowing current to the motor. Relays are readily available as mine uses a common relay used in HVAC service.

Knowing what we know now, this. I agree this is the most likely problem.

 

[RickP]

I don't know that much about central vacs specifically, so I'll defer to the ones who own 'em.

I'm just going off the builtinvacuum.com website:
1. Is the unit always running?
2. Disconnect house low voltage system.
3. Does it still run continuously?
4. No -- see #10.

10. Short in low voltage system.
Recent attic work or someone in crawl space?
Rats chewed through wire?
Disconnect any splices you can find & check continuity of short.
Worst case: re-route wire from any other working inlet or wire. (Possibly running wire behind baseboards, under carpet, in closets, or in air ducts)

 

[buco]

Hi guys.

So I just finished cleaning all contacts with rubbing alcohol, checked wiring at outlets. Everything looks fine.

Went to turn on vacuum, now I can turn it on and off at the vacuum without switching it off. I no longer have to unplug it to turn it off.

What does a relay look like?

Thanks again fella's.

 

[Nestor]

I'm a little confused, so just to clarify: When you pull the low-voltage wires from the vacuum terminals, and plug in the vacuum, does it start running immediately, or do you have to turn it on manually?

 

[RickP]

So does it work correctly now with your house wiring attached?

 

[buco]

I'm a little confused, so just to clarify: When you pull the low-voltage wires from the vacuum terminals, and plug in the vacuum, does it start running immediately, or do you have to turn it on manually?

The vacuum runs non stop. It doesn't turn off if the vacuum is plugged to the wall outlet, or unplugged.

 

[buco]

So does it work correctly now with your house wiring attached?

No. The only change is that I can now turn the vacuum on and off at the vacuum rather than unplugging it.

The vacuum still runs with nothing plugged into the outlets. I have to turn it on and off at the vacuum itself. Before it would turn on and off when the hose was plugged in the wall.

I'm stumped now. Next step relay?

 

[pattenp]

I have a central vac system. If the vacuum runs without the hose connected at a wall inlet or with the low voltage wire disconnected at the vacuum unit it's the relay in the vacuum unit that is stuck closed.

See if this helps...
http://builtinvacuum.com/education/motortroubleshoot.html

No. The only change is that I can now turn the vacuum on and off at the vacuum rather than unplugging it.

The vacuum still runs with nothing plugged into the outlets. I have to turn it on and off at the vacuum itself. Before it would turn on and off when the hose was plugged in the wall.

I'm stumped now. Next step relay?

 

[RickP]

No. The only change is that I can now turn the vacuum on and off at the vacuum rather than unplugging it.

The vacuum still runs with nothing plugged into the outlets. I have to turn it on and off at the vacuum itself. Before it would turn on and off when the hose was plugged in the wall.

I'm stumped now. Next step relay?

Yes, the vacuum owners have spoken! You should test the relay inside the vacuum first. With the house wires unplugged, try connecting the two low voltage terminals with a screwdriver or a short wire. Does the vacuum turn on when you connect those terminals and then turn off when you disconnect them? That's a good test of your relay. If that doesn't work, you'll have to open up the vacuum and test the board inside.