Variable flow control

[JJ]

I didn't end up buying an Artesian because of dealer issues, but they were a close second, mainly because the variable flow controls were so cool.  How do they do that?  Is is a variable speed motor or some flow diversion system?  How come other manufacturers are not offering something similar?

[Kyle]

If you have control over the rpms of a motor, it probably will not last very long.  Most motors are set to run high speed at 3400 rpm's, which is a little higher rpm's than your car cruising on the interstate at 80.  It might be OK if you use high continuous HP motors, but then you might not have enough power for heat and require 60+ amp breakers to operate.  A car lasts much longer on the highway because steady rpms.  City driving is start/stop.  It's purely marketing game Artesian is playing.

[JJ]

Well, the water flow actually does vary, whether they use a variable speed drive or not.  I'm just wondering how they do it?  I can't find it on their web site.

[Cgar]

It is an awesome feature, but it's also incredibly simple.  The motors are single-speed, and the flow control simply allows a small amount of air to be drawn into the water stream.  And voila, this decreases the amount of water flow.  The effect is like running the water flow through the jets with a 'dimmer switch'.  Very nice.

[JJ]

So it's like the air induction "venturi" that most spas (including artesian) have on the pressure side of the pump, but it's on the suction side?

[Cgar]

So it's like the air induction "venturi" that most spas (including artesian) have on the pressure side of the pump, but it's on the suction side?

Sure?  All I can say is that a very small amount of air enters the water stream when the variable flow control is set to low.  The water flow is effectively cut in half at the low setting.

[JJ]

Sorry, had my engineer hat on....

So the flow control allows air to enter the water stream between the filter and the pump, not between the pump and the jets?

[Kyle]

What about cavitation?

[JJ]

Technically I don't think mixing air into the flow stream prior to the pump is the same as cavitation.  As long as the pump does not lose prime, all that will happen is the pump will lose efficency.  Loss of efficiency means less flow for the same power, something you normally try to avoid, but in the case of Artesian, that's what they are after.

They sell it as a feature.  It is quite unique and seems to work well.

Anybody know how long Artesian has been doing this?