"Free Flow"

[truckmount girl]

Bob,

What are you using for a motor to push that overdriven #4? That can be a lot of stress on motor / coupler if the motor doesn't put out the torque to handle it...relieving with a free flow system works, but is not the most efficient way to accomplish your goal. At higher lift situations you are still stressing it, at lower lifts you are relieving too much.

You would be giving up too much performance in lower lift situations....at least for me, and still stressing your already overdriven system at high lifts like for flood extraction.

Even in your situation, I don't see where a dynamic relief system would not benefit you. Also using 2.5" hose straight from the tank, or a dual 2" (4 to the door) would be more efficient to accomplish your task in a single wand situation.

Take care,
Lisa

 

[Bob Savage]

Lisa,

I am using a Honda 24 HP air cooled motor. There is an 8" pulley ("B" Belt size) on the Honda, and a 7" pulley on the Roots #45 blower. There is also a tensioner pully on that belt loop.

That single B-58 belt will last for several hundred hours - no problem.

The Honda motor definitely does not bog down, even under a full load using dual wands.

Have a great 4th!

 

[Dolly Llama]

Assuming that the wand was in the same position before and after he actuated the relief valve, the reason why actuating the relief would help clear the hoses faster is it creates a "draw" further down the line.

Being the dumb "mocho redneck" I am.. :mrgreen:
guess I'm just too thick to grasp the hows and whys of introducing an air leak "down stream" creates more draw thru water/air filled hoses.
(other than the situation of having too much lift that can cause lock down at carpet interface on some carpets..especially with unglided wands)
Then the decreased lift would help prevent lock down

Even the gap in a glide is BEHIND the carpet/glide interface, the engineered gap adds cfm which creates an additional draw on the carpet.

I easily understand that one..as long as the glide or unglided wand isn't "locked down" at wand slot
It creates more aiflow thru the hoses


..L.T.A.

 

[Bob Savage]

Being the dumb "mocho redneck" I am..
guess I'm just too thick to grasp the hows and whys of introducing an air leak "down stream" creates more draw thru water/air filled hoses.

Larry,

The free flow doesn't create any more, or any less, water recovery, just the same as NOT using the free-flow setup.

Free-flow does however:

Work — by lessening the load on the motor, and the blower. It uses less fuel, and causes less strain on the machine components. Belts last longer, everything just lasts longer.

 

[Bob Savage]

Even the gap in a glide is BEHIND the carpet/glide interface, the engineered gap adds cfm which creates an additional draw on the carpet.

I easily understand that one..as long as the glide or unglided wand isn't "locked down" at wand slot
It creates more aiflow thru the hoses
..L.T.A.

Cap,

It doesn't create, or add more airflow through the hoses, it allows some of the existing airflow back into the hoses, so the airflow doesn't stop completely like it does when the wand locks tight onto the carpet (i.e., glide-less wand).

There is no need for a wand to lock tight to the carpet, because when it does, air movement comes to a standstill (remember the inverse relationship between Lift and CFM?). You can see this when you watch a clear-view vac filter moving water through the hose. Now cap off the end of that vac hose, and watch the water and air stop moving.

Release your hand, and watch the air and water moving again.

It's this start and stop that stymies airflow back to the recovery tank while you are cleaning.

 

[Jimmy L]

My "GLIDELESS" POS castex wand I repeat has "Breather holes" on each side of the slot to allow more air into the system and thus free flow.


And lets not forget air leakage around vac hose connects.

 

[Dolly Llama]

Thanks Bob
I do understand and am aware of all that

however, imHo, any air leaks/vac relief would be best when closest as possible to the WCI


..L.T.A.

 

[John LaBarbera]

I will disagree with almost everyone here because I have been using the "free flow" design for 16 years, and it does work. It works by lessening the load on the motor, and the blower. It uses less fuel, and causes less strain on the machine components. Belts last longer, everything lasts longer.

There is no gain in CFM using the free-flow setup, but you are also NOT losing CFM. A properly designed vacuum system will produce more vacuum than the hose can possibly use in the first place. You do drop some lift with free-flow, but not enough to effect water recovery at the wand.

Our TM uses a #45 blower, over-driven to 4150 RPM, going to 2 separate recovery tanks, with each tank having it's own 2" vacuum hose going to the TM panel. This makes the internal plumbing of the TM 4 to the front of the machine (2 separate 2" vac hoses). On the discharge side of the Blower (2.5" NPT), we have a 2.5" to 3" bell increaser, going to a 45º bend, then into another 45º bend to a 3" to 4" bell increaser, and finally into a Stoddard 4" NPT silencer. When running a single wand, we put a foam block into one of the 2" hose barbs to allow that amount of air to "leak" (free-flow), or, we run 4 to the door. With 4 to the door, there is no free-flow. I know you are laughing at the foam block thing, but it allows the correct amount of air to "leak".

When we run dual wands (which is almost every job), the free-flow becomes the 2 separate end-of-hose connections going to each wand - there is no open free flow device back at the TM.


So, anyone using dual wands, is using the free flow design whenever one of the tools is off the carpet or upholstery, whether they are aware of that or not.

Bob, you're a credit to this industry. Nice explanation. Thanks. I especially appreciate very much your matter of fact comments with out taking anybodies dignity away or talking "down" to others. Very nice.