On Thu, 6 Apr 2017 03:51:47 -0000 (UTC), "Danny D."
wrote:

On Tue, 04 Apr 2017 00:05:29 -0400, opined:

Amperage is only one indicator and doesn't tell you a whole lot - it
depends on the efficiency. A combination of water column and CFM is
required to really analyze a vacuum.

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.

My current system has an 8.4 inch Tangential bypass motor. I was
wrong on my last post - it's not Elite, it's Signature.
It is rated at 675 air watts and 147" vacuum.

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

I see it's a measure of efficiency.
https://en.wikipedia.org/wiki/Airwatt

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

It is also rated at
12.7 amps, whichn is an HONEST 2 HP (1524 watts) which means it needs
a dedicated 15 amp circuit.

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.

12 watts is a very low powered vacuum - 12 AMPS would be a relatively
powerful one.

For all you ever wanted to know, and more - including all the
terminology, see: http://canavac.com/buyers-guide/

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?
12/30/2014
https://groups.google.com/d/msg/alt....w/C-a-6iiVHrMJ

None of the outlets seem to be leaking overtly.
https://c4.staticflickr.com/8/7500/1...7989dca3_c.jpg

The 25-foot long external hose is clear of obstructions:
https://c4.staticflickr.com/8/7573/1...fb4ff8bd_c.jpg

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.
https://c4.staticflickr.com/8/7533/1...abc9b313_b.jpg

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.
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.