WOW WOW MORE VACC WOW HOW WHY

[Johnnyone]

OK

HERE THE QUESTION

WHAT IF YOU RAN 2.5 VAC HOSE 50 FT THEN REDUCED TO 2 INCH HOSE
THEN INTO THE HOUSE

OR

WHAT IF YOU RAN TWO 2 INCH HOSE 50 FT INTO A Y THEN REDUCED TO 2 INCH HOSE INTO THE HOUSE

WHAT WOULD GIVE YOU STRONGER VACC?

 

[adamh]

I have done both and don't ask me why or how but the 2.5" is better. IMO

 

[Kevin B]

Less surface area for resistance with the 2.5 - Just like if you ran 3, it would be better as well.

 

[Farenheit251]

Pi X Radius squared. The Pis cancel out so just compared the radius squared. Each 2 inch hose is one for a total of two. The 2.5 is 1.25 squared which is around 1.5. So in theory the 2 2 inches deliver more if you've got the machine to deliver it. With a 4005 blower I've only got a 2.5 inch port so any more would be a waste.

 

[Greenie]

then add to that math the "flex ducting" variable, if it were pvc it would be a different story, but it's not, flex ducting has a lot to do with the frictional loss of two hoses vs: a single larger hose.

 

[Johnnyone]

If the math works add the two 2 inch hoses that would make a total of 4 inch hose in theory

That would make it 1.5 inch bigger than a 2.5 inch hose, more air flow less air friction?

 

[Shane T]

Has any one done side by side comparison of the standard vacuum hose vrs the "smooth bore" type? Seems there would be less friction with the smooth bore as there are no ribs inside but maybe its insignificant.

 

[KBRENNY]

The area of a circle is calculated by: 3.14 x (radius x radius).
2" hose would be 3.14 sq inches of area for each hose,
this means two 2" hose would be 6.28sq" of area.
A 2.5" hose would be 4.91sq" of area.
I agree with Greenie that there is something to be said for the frictional loss due to the walls of each setup.
While the 2.5" hose has 7.85 inches of wall circumference
two 2" hoses would have a combined 12.56" of wall circumference.
All the air that passes through each setup will have to deal with the friction from the inner wall of the hose.
While the 2.5" hose has 22% less surface area it also has 38% less frictional area.
While I have never ran the two 2" hose setup I can honestly say the 2.5" hose was one of the best improvements I have made to my system.
I think the above math would explain the mixed results and opinions from the different hose combinations. I believe they are so very close in performance it is 6 to 1/2 dozen in opinions.
The reason I went with the 2.5" is I only have to deal with one hose all the way from the truck to the wand shortening my setup and tear down time.
Reel space was also a consideration 2.5" hose takes up less space on the reel compared to two 2" hoses in the same length.

 

[Jack May]

I have a typical 200' reel but only ever carry 3 lengths on this van. Will that reel hold 2x 2.5"x50' and 1x 2"x50' lengths?

John

 

[Shane T]

John, I have a high profile reel. The diameter is 44" and the circular tubes are 12" apart. It would just barely hold 200' of 2" hose. I mounted the reel upside down and just today I received a 50' section of 2 1/2" and am now able to roll up 150' of 2" and 50' of 2 1/2". Being upside down it can't fall off the top. It worked great.

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This was before.

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[KBRENNY]

I had 275 feet of 2" crammed on my reel and when I added the 50' section of 2.5" hose I had to remove 75' of 2" hose (it is still crammed on the reel). 1.5 feet of 2" hose should be about the same as 1 foot of 2.5" hose

 

[floorguy]

kevin what is your blower size???

 

[KBRENNY]

4MP

 

[alazo1]

Sorry I can't help but I love the side doors on both sides.

Albert

 

[Ron Werner]

2" hose would be 3.14 sq inches of area for each hose,
this means two 2" hose would be 6.28sq" of area.
A 2.5" hose would be 4.91sq" of area.

3" hose has an area of 7.065 sq"
It does take up some reel area, but it seems to work quite well.