Vacuum cleaner amperage and suction power relationship

What you say makes sense in that the amperage is only an indirect indication of potential sucking power and air flow.

But how does a homeowner, "easily" obtain sucking power and air flow?

Of course, I put my hand over the opening, and that's about all I could measure.

Air watts? I never heard of "air watts" until now.

I see it's a measure of efficiency.

I don't really care about efficiency since a vacuum is just used sporadically. What I care about is sucking power. :)

One of the vacuum cleaners says it's 12.0 watts, and it doesn't flip the circuit breaker, so, I'll take that as an upper range for portable vacuum cleaners.

That site is nice but it doesn't help for troubleshooting an existing central vacuum setup.

I have a central vacuum cleaner, but I gave up on it years ago after asking here on this newsgroup how to debug why it had almost no air flow.

How do you debug low suction in a central vacuum system?

None of the outlets seem to be leaking overtly.

The 25-foot long external hose is clear of obstructions:

The motor works and the motor filter is clean.

I suspect there is either a blockage inside the walls or a tear inside the walls.

So it's effectively dead. I can't imagine how one "fixes" that, without ripping the walls out, which I'm not going to do. Ever.

Both of the two central vac units that I have owned - diffferent makes - had an additional inlet at the machine - if yours does - you coulld check IT for suction - carry your hose to the garage.. and listen to the motor.. Also - if IT doesn't have suction - ta-da. John T.

Inlets?

I never noticed if there is an additional "inlet".

There is an outlet for exhaust which is near the vacuum motor and which blows to the outside of the house.

I guess I could take it apart and disconnect the main inlet hose though.

I'll look later on today when it gets light and see what I can see.

Yes...No!

True this is a home repair group. But here you have a valuable central vac system that you will definitely get repaired if you ever move out. If you can't figure out the problem, it's worth spending the money now and getting the use out of it yourself.

My in the wall piping is white vinyl pipe like you see in water waste runs.

Isolate the motor/vac from the in-house piping by removing and sealing the connection(s), then use the outlet on the vac itself to see if you have suction there. That will save you time trying to clear pipes that might not be the problem.

Like hubops, my unit has an outlet right on the vac unit that is not part of the in-house system. Disconnect the in-house system, seal it with a cap or duct tape, then use the outlet on the vac.

Since you are trying to play qualified vacuum repairman, you might want to by a tool the repairman would use the actually measure the vacuum. Not sure what it's called, but pretty sure it exists.

I have a Pullman and it too has an inlet right on the unit and a switch nearby that turns on the unit. Seems very logical that all of them would have that handy feature, but then who knows.

Inlet - referred to as a utility valve by Beam :

A little flapper door covers a suction point where your hose can be inserted. ... your vacuum hose, that is. John T.

The CanaVac can be used bagless too, but we find the bag more convenient. The unit is in the furnace room in our basement, and vents to the outside.

The unit is already trying to suck that way- unsuccessfully so I'd try sucking out the inlets.

A whole lot easier than tearing apart many of the "standard" vacuums today.. I can isolate why mine doesnt start by turning it on manually with the unit-mounted switch. If it runs then and not when plugging in the hose, it is a remote wiring issue. If not it is a unit problem. The "switches" on the outlets are all in parallel, so if none work you know where to look (common wiring). If only one doesn't work you also know where to look.

The tubes are generally polycarbonate or PVC. Just for giggles, disconnect the pipe from the unit and check suction AT the unit. If suction is good, you have a pipe issue. Reconnect the pipe and check suction at the "service" outlet - on both of mine there is a place to connect a hose directly to the unit. If you now have NO suction (or very little) you have a leak, if you have good suction you likely have a clog. If no suction at any of the outlets in the house, the clog is close to the unit (shared pipe) - snake from the bottom. If you can stick an air hose up the pipe and blast with pulses of air as you push it up, you should be able to dislodge anything stuck in the pipe. A

Also, with the system running (turned on with the system switch) have someone open the outlets one at a time and see how the motor pitch changes.

I just gave you troubleshooting instructions - and my whole system was installed without opening walls, so it can be repaired the same way. If it was installed when the house was built, you MAY have a problem. The unit installed at our church was installed when the renovations were done, and leaked like crazy - the original installer ended up paying someone who knew what they were doing to come in and fix it - including holes in the drywall ceiling. Incredible how an "installer" thought taped joints were going to work transitioning from the plastic to metal and back (apparently he thought he had to use metal transitions through concrete floor and through walls) Just about every taped joint leaked.

They virtually never have wide bends.in the walls.

Good idea. I just suctioned backward, all the in-house inlets but I didn't get much by way of debris.

Here's basically what I got out of the more than half-dozen inlets:

All but one seemed clean, where the one most used had a little bit of debris I could hear hitting the vacuum container sides.

It took a while to get the hoses right because they're all the same size on the large end and the same size on the small end, where I needed to fit together a large-to-large using this gasoline tube piping.

I changed vacuum cleaners from the Eureka floor type to use the Costco tin-can type with the air blowing out visibly, where it seemed that none of the vacuum inlets is clogged because the air blew out pretty well.

You could also use an electricians fish tape to find out where the obstruction is.

My fish tape won't go around the elbows in the central vac pipe very easily- not at all if one bend is 90 degrees to the previous bend.. I find a 3/8" flexible air hose is about all that will easily traverse multiple bends - and even that takes some patience.