Dual wanding, Big blowers and 2.5 hose

[Walt]

Do I have this correct? Larger hose diameter reduces the need for higher levels of lift to get higher cfm to the wand. If this is true, then blowers should be designed with higher cfms than lift.

For instance a 6008 blower is capable of producing 600 cfm at 18hg. However, with larger hose you might actually be limited by the cfm if you were dual wanding - each hose being able to carry more than half of the cfm. Wouldn't a blower with greater cfm but lower lift be more effective in this senerio or does every thing change once the want comes in contact with the carpet?

 

[TimP]

What you're missing is that usually you're not running that high of lift. And when you run two 2.5" hose runs you're definitely not going to get that high of lift. That's just the safety point and the lowest CFM possible of the blower. When you're running lower lift you're blower is actually more efficient with the CFM which means it's moving more air at less lift. And that's what you want, it really doesn't take much lift to move the water from the carpet to the waste tank. And it's only really needed for the drag in the hose and long hose runs. Also the more CFM you have the faster the water is going to get to the waste tank so you wont need as much lift to move it either. So CFM is your friend when dual wanding, lift helps but you don't want it caused by restriction of hose you want it pulling the water through the hose and not wasted on drag (restriction in this case).

Just think about it.....the longer the straw the harder you have to suck to get air moving. Also the more narrow the straw the harder you have to suck. If you enlarge the straw you can have a longer straw or you don't need as much force or lift in this case to get the job done.

 

[Greenie]

To add to Tim:

In the 68 blower example above, you may have your relief valve set to open at 18" with a resonable restriction (say 50%+) restriction on the 5" plumbing, so you will always be "at 18"hg" according to industry standards, but with large enough hose and enough of them, you will never ever reach a point of restriction where an 18" relief valve actually opens, the larger hoses themselves are flowing the FULL volume of air, so yes your vacuum gauge might show 10" while actually cleaning, but rest assured you have the equivalent of 18" ON the carpet. Think of it as Thump Factor, when a wand hits the carpet on a system showing 10"hg with that much CFM behind it, you will know what Thump Factor means, and that CFM is responsible for a lot of that Thump.

With all that said, I think you will see a lot more 770 cfm 59 blowers in use than 600 cfm 68 blowers....it's just a Shame to see 770 cfm restricted by tiny 2" hose.

 

[Cousin]

And so do we need to remove the restriction at the wand, and make those bigger too?


M

 

[Jay D]

So then you can use a standard vac relieve valve if you never have more than8 to 10 hg on the guage? So is a kunkle or bayco really needed then if CFM rules over HG? I am just trying to understand the shift from hg to cfm. :?

 

[Rex Tyus]

So then you can use a standard vac relieve valve if you never have more than8 to 10 hg on the guage? So is a kunkle or bayco really needed then if CFM rules over HG? I am just trying to understand the shift from hg to cfm. :?

It is really not a shift from hg to cfm so much as a better understanding of what is going on. For far too long some manufacturers have purposefully incorporated restrictions in their units so they could achieve a given "LIFT". Once your max lift is showing on the guage from simply laying out the hose, you better stop adding sections. Each foot of hose to follow will dramaticaly alter you vacuum. There are too many variables to say what is absolutely correct for every system or situation. It is a safe bet that a precision relief will offer more consistency than a typical spring loaded valve. As I said how much improvement will depend on individual systems, and how long the hose run is.

And so do we need to remove the restriction at the wand, and make those bigger too?

M

There is a point of deminishing return. A 2" wand with a hybrid glide consumes less than 1 hg of restriction. And that is at the end of the hose run. Without a glide when off the floor it is about .25 hg worth. However when you put an unglided wand on the floor it will get lock down and not fuction properly (I only add that to head off the certain idiotic remarks about being better without a glide that would surely follow).

 

[lance]

So how does this way of thinking affect the engine hp needed for peak performance? It sounds like 2.5 inch hose allows less hp needed to drive the system than when 2 inch hose is used.

So is this true: a 2547 with 2 inch hose and bayco set at 15" hg will bog the
engine but with 2.5 inch hose the engine will not bog down?

 

[Rex Tyus]

So how does this way of thinking affect the engine hp needed for peak performance? It sounds like 2.5 inch hose allows less hp needed to drive the system than when 2 inch hose is used.

So is this true: a 2547 with 2 inch hose and bayco set at 15" hg will bog the
engine but with 2.5 inch hose the engine will not bog down?

That is one for Greenie.

I will be so bold as to say the 2.5 conversion will reduce the load on the engine. I just can't say how much. Especially since the internal plumbing is an unknown and a key part of the equation.

 

[lance]

That's what I was thinking also Rex. I also think the plumbing is a big factor. So much so I don't think it's worth it to buy a TM that isn't plumbed up to "Mikey Board" standards.

I'm not sure but my question might also be different based on if the system was direct-coupled or belt driven. I like belt driven systems as they seem to offer more options for engine/blower speeds.

 

[Mike Draper]

I hooked up my 2.5" to my buddies vortex and the noise reduction was about 30%. It was significant enough to realize the engine was not having to work as hard with 2.5.

 

[Cousin]

I hooked up my 2.5" to my buddies vortex and the noise reduction was about 30%. It was significant enough to realize the engine was not having to work as hard with 2.5.

Might that reduce your heat availability, through heat exchangers, Mike.



M

 

[Mike Draper]

Might that reduce your heat availability, through heat exchangers, Mike.

I suppose it might if your running a Blower HX. That's a good question though, and I don't know for sure.
However, I would think that it'll probably extend the life of your engine and blower since it's probably not under such a load as it is with 2". I don't think the Vtex or AT machines run blower HX's.

 

[TimP]

The newer Vortex machines run Blower exchangers and have even gotten rid of the heated fresh water tank. They claim it allows them to get to peak heat faster especially while filling an empty tank and in the morning.

 

[steve frasier]

it's just a Shame to see 770 cfm restricted by tiny 2" hose.

dude that wand is a bitch to push and pull even with a hybrid glide

I ran 100' of 2.5" and then had a 20' whip, I was sweating so bad from the work, had to be real careful or a tight bend would collapse the 2.5" hose

 

[Greenie]

Reading over Rex's explanation above makes me proud to have him here.
My work is done, you guys are problem solving and using common sense to show the obvious choke points in vacuum systems, you don't have to be an engineer to teach an engineer a thing or two.

I would like to add that adding "stress" to a system by making it work harder to make more "heat potential", isn't always a good thing, this specifically address heat exchangers and fuel consumption.
And...the only place we want "restriction" is at the wand/carpet interface, everything past that needs to be open flow.

 

[Walt]

Steve,

Does your V have 770 CFM?

 

[Larry Cobb]

Wait just a minute !!

Let's think about what we are trying to achieve at the carpet.

2.5" Vac hose will provide more lift at the wand (less loss).

More Lift at the wand, which corresponds to more CFM thru the fibers.

More Lift & more CFM will be more POWER required from the engine,

not less.

Larry Cobb
Engineer

 

[TimP]

Wait just a minute !!

Let's think about what we are trying to achieve at the carpet.

2.5" Vac hose will provide more lift at the wand (less loss).

More Lift at the wand, which corresponds to more CFM thru the fibers.

More Lift & more CFM will be more POWER required from the engine,

not less.

Larry Cobb
Engineer

The blower isn't pulling as much of a load because of less restriction and therefore less power required to keep the blower spinning and less fuel consumption. The blower may be pulling harder at the wand but that don't mean it is pulling harder at the blower. The RPM's are going to be the same but there is going to be more fuel required to keep the RPM's (or drag on the blower with more restriction) and the motor is going to pull more fuel to keep up.

It's easier and requires less energy sucking a drink from a long wide straw than it does with a slender straw. Compare your McDonalds straw vs your Burger King straw.....think about it. You can suck down your drink faster and with less energy at McDonalds vs Burgerking.

I suggest you look at real world #'s and the guys who have done the upgrade are in consensus about fuel consumption power at the blower compared to non 2.5 upgrades.

 

[Rex Tyus]

Wait just a minute !!

Let's think about what we are trying to achieve at the carpet.

2.5" Vac hose will provide more lift at the wand (less loss).

More Lift at the wand, which corresponds to more CFM thru the fibers.

More Lift & more CFM will be more POWER required from the engine,

not less.

Larry Cobb
Engineer

Larry, reread the entire thread. Then reread your post. If you still don't understand I will TRY and explain it to you ONE MORE TIME.

 

[Brian R]

So the use of a Kunkle valve as asked earlier wasn't explained I don't think.

with just the 2" all the way to my 2" wand I am noticing that I am not getting close to 15 hg the I would get with my 1 1/2" . So I would understand that just a normal valve should be plenty and a Kunkle would be a waste of money? Yes?

 

[Rex Tyus]

So the use of a Kunkle valve as asked earlier wasn't explained I don't think.

with just the 2" all the way to my 2" wand I am noticing that I am not getting close to 15 hg the I would get with my 1 1/2" . So I would understand that just a normal valve should be plenty and a Kunkle would be a waste of money? Yes?

I don't have a precision relief valve on my unit. Thus I am reluctant to offer advice on such. Before I bought a kunkle/Bayco I would make the 2.5" upgrade. That is just me. I have heard however that some units benefit more from the precision relief valve and others benefit more from the 2.5" upgrade. Greenie keeps good notes on which (I think). Maybe he will see this and chime in. Sorry I can't be of more help.

 

[TimP]

So the use of a Kunkle valve as asked earlier wasn't explained I don't think.

with just the 2" all the way to my 2" wand I am noticing that I am not getting close to 15 hg the I would get with my 1 1/2" . So I would understand that just a normal valve should be plenty and a Kunkle would be a waste of money? Yes?

A Knuckle, or Bayco valve is good for not letting any air through the relief until a set point is reached. Which is usually 14-15 HG. Spring relief valves can be set to 14-15 but they start to relieve way before their set point. A precision valve can and will get your more lift and maybe a bit more cfm through the actual hose.


2.5 hose will allow the same effect at the wand due to less restriction and less lift which will keep you from getting up to a point where your spring valve is starting to leak. However with both you will have the best of both worlds, but I don't know if it's worth having a precision valve with 2.5 unless maybe you're doing long runs and you tend to be on the high end of the lift and you need a bit more umph out of your blower.


Keep in mind that blowers pull less CFM when they are under more lift. And most cfm for blowers are rated at a max cfm and are capable of more cfms at lower lift which is what you want, kinda like you have a bigger blower at the wand.

 

[Brian R]

Because I was going to order a 50' 2 1/2" from Greenie I think..if he carries them and the shipping isn't too much.
What you said sounds right to me and I dont think I will need the Kunkle because I rarely pull out that much hose..but the increased airflow will do me good.



As Uncle Milty used to say..."you pull our your hose first...I'm only pulling out enough to win."

I didn't even know that he cleaned carpets...maybe he was talking about something else? :mrgreen:

 

[Out of Character - 0]

Brian, put 100ft of hose on that commander and feel the vac relief. You'll know if you want a kunkle. Both my w/m's were very leaky, at a minimum you may want to duct tape some of the relief holes.

 

[Brian R]

I do 100 ft every job at least. I don't feel the vac relief at all. With the glide and the 2" wand I don't get close. I am running at about 11 I think while I am cleaning. But I have to depend on my senile old dad so that could be inacurate.

 

[Larry Cobb]

Rex;

More Lift & more CFM at the wand-carpet interface will be

more POWER required from the engine.

Larry

 

[Rex Tyus]

Rex;

More Lift & more CFM at the wand-carpet interface will be

more POWER required from the engine.

Larry

You didn't reread the thread did you?

hate to be in constant disagreement with you. I really do. You seem like a good guy. But here goes.

If the AVAILABLE or operating lift is acheived through reductions in restrictions it will not. If the only variable in the equation were to acheive more lift and cfm then you would be correct. HOWEVER, that is not what is being discussed here. If you have your car set at 70 mph with the cruise control and you go DOWN a hill are you using more or less energy? I will leave the last word to you. I really don't have the energy to debate you tonite, other than to say it often appears you want so much to disprove the improvements proper plumbing makes you will make statements that simply don't apply before you think them through.

Anyone that did not ride the short bus to school will surely understand the discussion. I would certainly think an "engineer" would have the intellectual capacity to grasp it.

 

[Mike Draper]

Let's think about what we are trying to achieve at the carpet.

2.5" Vac hose will provide more lift at the wand (less loss).

More Lift at the wand, which corresponds to more CFM thru the fibers.

More Lift & more CFM will be more POWER required from the engine,

not less.

Larry Cobb
Engineer
Wait just a minute !!

Let's think about what we are trying to achieve at the carpet.

2.5" Vac hose will provide more lift at the wand (less loss).

More Lift at the wand, which corresponds to more CFM thru the fibers.

More Lift & more CFM will be more POWER required from the engine,

not less.

Larry Cobb
Engineer

when a jet is going cruising speed at 30,000 feet, it's more economical. So just becuase it's going faster now than at takeoff doesn't mean it's using more fuel and more power, it actually using much less power and fuel.

 

[TimP]

When you run 2.5 hose your level of HG ATM is LESS.....BUT the level of HG ATW is higher due to less restrictions (less drag or friction).


When you figure how much fuel is going to be consumed you look at what the machine HG is.

What uses less fuel 2 HG ATM or 11 HG??? clear answer 2 HG. Also every fuel usage chart I've seen for TM's an HG rating related to the consumption. Like the following

Real world 14-15 HG or 11-12 HG. I would say 11-12 HG and that's what people are seeing as a difference when using 2.5" hose vs 2" throughout. It's not a difficuilt concept as Rex has stated. If you can'g grasp it or don't believe it.

Run a test yourself!! Don't start telling people how it is unless you have tested it and that's what gripes me most about what you're saying Larry. Bring us some proof!!!

 

[Jay D]

I am just asking a question so don't start slinging poo. Have you guys hooked up a HG guage between the wand and the hose at 100 ft and what did it read at the machine VS at the wand. I'm Asking nicely.