Hose diameter flow test

taselton2

Softwashing Instructor/Moderator
I ran some tests last weekend on my pump with three different diameter hoses to see just what I could get at the end of 200'. The tests were done to maximize my efficiency and not for starting up more "hose wars". The pump pulled water from a supply tank and was attached to each line via a 3/4" x 4' supply hose coming directly out of the pump. The pump open flowed 14 gpms and had a "static" pressure of 150psi. Some hoses have different liners that flow with less resistance, but these hoses were all that I had. The picture below shows what each hose "open flowed" (no nozzle) at 200'. I did test the flow/psi with different nozzles and the higher flowing lines produced more psi every time. As you constrict the flow you generate the psi, more flow = more psi as long as you have good pressure output at the pump. I made up a nice chart, but it got all messed up when I previewed it. Pumps are different, but the flow capabilities of hoses are what they are. The longer you go the larger you need to get max out of it, the same is true with electricity. I am in the fire service and this is all common to me since I drive and pump fire trucks (10yrs) when I'm not washing roofs and houses. When we need to go a good distance we lay the 5" lines.
 

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Apple Roof Cleaning

Roof Cleaning Instructor
I ran some tests last weekend on my pump with three different diameter hoses to see just what I could get at the end of 200'. The tests were done to maximize my efficiency and not for starting up more "hose wars". The pump pulled water from a supply tank and was attached to each line via a 3/4" x 4' supply hose coming directly out of the pump. The pump open flowed 14 gpms and had a "static" pressure of 150psi. Some hoses have different liners that flow with less resistance, but these hoses were all that I had. The picture below shows what each hose "open flowed" (no nozzle) at 200'. I did test the flow/psi with different nozzles and the higher flowing lines produced more psi every time. As you constrict the flow you generate the psi, more flow = more psi as long as you have good pressure output at the pump. I made up a nice chart, but it got all messed up when I previewed it. Pumps are different, but the flow capabilities of hoses are what they are. The longer you go the larger you need to get max out of it, the same is true with electricity. I am in the fire service and this is all common to me since I drive and pump fire trucks (10yrs) when I'm not washing roofs and houses. When we need to go a good distance we lay the 5" lines.

Yeah, no more wars!
It is interesting your real world results closely mimic what the flow calculator predicted.

Computer aided design or CAD for short is a powerful tool.
But I still do not completely trust it.

I like real world measurements to confirm what the computer predicts.

To be fair to some guys using, and recommending 3/8 hose, it can work.

The real story here is that the more GPM a pump has, the more important larger diameter hose becomes.

Too bad you can not reduce flow to say 2 gpm, and repeat the test ?

The computer predicts larger hose is still better at lower flow rates, but not by much.

The slight increase in flow for those using under 2 GPM may not be worth the extra weight and cost to some ?

My computer simulations show that a small shurflo pump of 1.8 GPM will spray just fine with 3/8 hose, and just slightly better with 1/2 or 5/8 hose at 200 feet.

I think this hose "war" got started by many of us thinking about different pump scenarios.

I have always used, and suggested the higher GPM Shurflo's, and large Gas pumps.

Because of their higher flow, they work better with large hose.

But the people who use the smaller gpm pumps know that their pumps work just fine with the 3/8 hose.

It is true that bigger hose is better, but in some cases, small hose is good enough.
 

taselton2

Softwashing Instructor/Moderator
Chris, you are exactly right about the lower flowing pumps, 3/8" is what I used years ago and 1/2" or 5'8" is better, but how much at that flow? I will find out exactly. I depend on the gpms to work for me so I need as much flow as I can get. I didn't think to much about the lower flowing pumps because when I ran shurflos & flojets back in the day I would get so frustrated at how long it took to apply. Then I had to bring a garden hose up on the roof and rinse at whatever flow/pressure I could get off the house. I'm not knocking the shurflo set-ups or people who use them, I just had to have a more efficient & pratical method. Flowing the higher gpms allows me to clean homes as well as roofs with the same pump and using just one hose for application and rinsing. I don't want anyone to think I'm trying to start something, the set-up I'm using just works better for me. I purchased two flowmeters to test incoming flow to my pumps and the output to build exactly what I needed. I will run some test with a shurflo pump when I can. I was not aware that the swivel at my hose reel knocked 2gpms off the flow. I will fix that by switching to my new reels that have a 3/4" swivel and waterway.
 
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Russ Spence

Commercial Pressure Wash Expert and PWI Admin
hey i better check mine ,i had nooooooo idea that it would restrict that much flow
 

taselton2

Softwashing Instructor/Moderator
hey i better check mine ,i had nooooooo idea that it would restrict that much flow

Russ, if you're not flowing high gpms it may not effect yours too much. You can help it some if you want. If your swivel is in good enough shape to take it apart without damaging it, you can make it flow better. You can take the outer snap ring off and slide off the "doughnut" part and it will expose a couple of small holes that the fluids travel through. You can "gently" drill out those holes or make some more. When you do this, you make the swivel a little weaker so be sure not to over do it. I did this on my intake hose reel with no problems, but I never checked to see just what difference it made.
 

Apple Roof Cleaning

Roof Cleaning Instructor
here is the computer predictions Tim
The first example is 3/8, the second 1/2, and the third 3/4 Hose.
Unfortunately, the flow loss calculator has no 5/8 hose setting.
This is for 200 feet of straight pipe, coiled hose has more loss.

We have lost 28 feet of head with 3/8 Hose!
This means that the higher the roof is, the less spray you have, not good!
Every Shurflo owner has noticed that their pumps do not spray as well on 2 story roofs.
As can be seen, it is the hose's fault, not the pumps.

This is your input:
fluid: 0 % solution
fluid temp F: 80F
flow rate GPM: 2
pipe size in: 3/8
pipe length ft: 200
pipe material: S
These are the results:
velocity ft per second: 3.3590
Reynold's Number: 15036.7279
friction factor fa: 0.0340
friction factor f: 0.0337
head loss ft: 28.7408
pressure loss psi: 12.4294

This is your input:
fluid: 0 % solution
fluid temp F: 80F
flow rate GPM: 2
pipe size in: 1/2
pipe length ft: 200
pipe material: S
These are the results:
velocity ft per second: 2.1146
Reynold's Number: 11930.6856
friction factor fa: 0.0342
friction factor f: 0.0339
head loss ft: 9.0822
pressure loss psi: 3.9278

This is your input:
fluid: 0 % solution
fluid temp F: 80F
flow rate GPM: 2
pipe size in: 3/4
pipe length ft: 200
pipe material: S
These are the results:
velocity ft per second: 1.2057
Reynold's Number: 9008.8851
friction factor fa: 0.0350
friction factor f: 0.0348
head loss ft: 2.2874
pressure loss psi: 0.9892


flow calculator developed by Michael J. Rocchetti PE
Back to the Calculator
 
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Mike Sullivan

New member
Great thread Tim. I would be interested to see a test on the 12V Delavan 5.3gpm 60psi pumps. I want to upgrade from my 12V Flojet 5.0gpm 45psi pump, and was wondering about upgrading from 5/8 hose to 3/4 hose for running dual 5.3gpm Delevans @ 10.6gpm.
 

Mike Sullivan

New member
Funny how when I recommend larger hose on higher gpm pumps like the Flojet and Delavan over at some "Internet scene" and I just get ignored as if the pros over there have no use for running a more efficient operation. God forbid we should get work done faster and make more money in a shorter period of time.
 

Mike Sullivan

New member
Hey Chris, a guy named David Batts from Rocky Mount, NC called me about getting into roof cleaning. I told him about you and said you would be glad to help him out if he decides to call you.
 

taselton2

Softwashing Instructor/Moderator
Great thread Tim. I would be interested to see a test on the 12V Delavan 5.3gpm 60psi pumps. I want to upgrade from my 12V Flojet 5.0gpm 45psi pump, and was wondering about upgrading from 5/8 hose to 3/4 hose for running dual 5.3gpm Delevans @ 10.6gpm.

Mike, you can order a flowmeter from Espec, I think they are about $200 and add a pressure gauge at one end. I suggest this to anyone who is serious about being efficient with thier work. If you don't own one how can you compare different configurations to see what is best for your needs. I think the guys on the other sites are good guys they just do thier set ups differently and they work fine for them. Some companies prefer "a lot of a little" and some prefer "a little of a lot" that's all. I have been at this for 13 years and I have tried a bunch different ways to make my cleaning methods the most efficient, pratical, and durable. I would think that you would see a difference by switching to 3/4" for sure, but you are doing pretty good with the 5/8". The 60psi may hinder that flow at long distances, but I would run your own test and know for a fact.
 

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Mike Sullivan

New member
Mike, you can order a flowmeter from Espec, I think they are about $200 and add a pressure gauge at one end. I suggest this to anyone who is serious about being efficient with thier work. If you don't own one how can you compare different configurations to see what is best for your needs. I think the guys on the other sites are good guys they just do thier set ups differently and they work fine for them. Some companies prefer "a lot of a little" and some prefer "a little of a lot" that's all. I have been at this for 13 years and I have tried a bunch different ways to make my cleaning methods the most efficient, pratical, and durable. I would think that you would see a difference by switching to 3/4" for sure, but you are doing pretty good with the 5/8". The 60psi may hinder that flow at long distances, but I would run your own test and know for a fact.

I think I'll just stick the end of the hose in a five gallon bucket and time it on my stop watch. Thanks for the reply Tim.

I'm very impressed with your photographs on your website, very well done. You are one hell of a good photographer. Great consistant camera angles and strong composition on your before and afters, makes a huge difference
 

Apple Roof Cleaning

Roof Cleaning Instructor
i have two 3.4 gpm shurflos in a dual set up----- with a 5/8 hose (200 feet)
Russ, before the Delevans came along, that dual shurflo setup with 5/8 hose was what we suggested for years.

The increased flow and pressure of the dual Delevans you are thinking of getting will make you even faster, and allow you to make your mix weaker too.

Like Tim said, one can clean either way.

You can use a little of a real strong solution, or a lot of a safer, weaker one.

We find low flow pump/hose setups leave too many spots.

To each his own.

I just hit the "Tri Fecta" , 3 neighbors roofs got done.

And, these customers were special, they were sent to us by a guy who puts up Christmas Lights we met at a Sports Bar.

Like me, he is a die hard football fan.

As the last guy handed me his check, he said "Gosh, I am a Pharmacist, and you just made over 1000.00 in less then 3 hours"!

I put my hand out, told him my back hurt from doing "all that work", and told him to please pass the Motrin, LOL :cool:
 

Apple Roof Cleaning

Roof Cleaning Instructor
Mike, you can order a flowmeter from Espec, I think they are about $200 and add a pressure gauge at one end. I suggest this to anyone who is serious about being efficient with thier work. If you don't own one how can you compare different configurations to see what is best for your needs. I think the guys on the other sites are good guys they just do thier set ups differently and they work fine for them. Some companies prefer "a lot of a little" and some prefer "a little of a lot" that's all. I have been at this for 13 years and I have tried a bunch different ways to make my cleaning methods the most efficient, pratical, and durable. I would think that you would see a difference by switching to 3/4" for sure, but you are doing pretty good with the 5/8". The 60psi may hinder that flow at long distances, but I would run your own test and know for a fact.
Unfortunately, the free online Flow Calculator has no provisions for a comparasion of 5/8 to 3/4 hose.

But, as can be seen from the posted flow calculator examples, and especially Tim Asleton's Real World testing, bigger hose is always better, especially at higher flow rates.

As can be seen in the computer predictions at a flow rate of 2 GPM, 1/2 inch hose is considerably better then 3/8, but going up to 3/4 hose on a 2 GPM pump yields little benefit.

I wouldn't do it, and put up with wrist busting 3/4 hose for little benefit.

Another real world advantage to using larger hose is it doesn't get under the roof shingles as easy.

I have sliced up a few roofs back when we first started using that thin 3/8 hose.

Interestingly enough, Jon Fife, and old acquaintance from the Delco board uses 1 1/2 inch hose for his non roof cleaning work.
 

JFife

Member
FOR MEDIA BLASTING!! Very heavy. Kinda got to haul it over your shoulder like a firehose. I'll take some pics of the guys tomorrow and show you. But from that aspect, all you are saying in regard to hose size is correct....farther we get from the pot, the larger diameter hose we have to have. At 100' w/ 1 1/2", beyond that we begin to drastically lose pressure and probably volume, though that is harder to determine....but without the pressure, it doesn't matter.

Few thoughts:

1) With that volume, why wouldn't guys use that to applicate and wash houses?? Seems easier, might reduce washer use.

2) What are the reasons the guys are still using 3/8" on roofs? You can get more hose on a reel, lighter, maybe "high flow" is too high for some, ......are these the reasons other guys aren't using 5/8" or something?? Just curious, I've seen the fights, but never analyzed.
 

Mike Sullivan

New member
2) What are the reasons the guys are still using 3/8" on roofs? You can get more hose on a reel, lighter, maybe "high flow" is too high for some, ......are these the reasons other guys aren't using 5/8" or something?? Just curious, I've seen the fights, but never analyzed.

Don't know, pride I guess. Some guys refuse to listen or try something new. It's like using a computer that's 10 years old. Yeah it works, slow as hell. I guess if they have the patience and don't want to grow or compete with the big boys then knock yourself out.
 

Mike Sullivan

New member
As the last guy handed me his check, he said "Gosh, I am a Pharmacist, and you just made over 1000.00 in less then 3 hours"!

I put my hand out, told him my back hurt from doing "all that work", and told him to please pass the Motrin, LOL :cool:

That's awesome man! Gotta love those jobs all in a row like that. Cuts way down on the driving all over creation time.

I take it you're being sarcastic, your crew does the work and you go shmooze with customers and their neighbors, right?
 

Apple Roof Cleaning

Roof Cleaning Instructor
Funny how when I recommend larger hose on higher gpm pumps like the Flojet and Delavan over at some "Internet scene" and I just get ignored as if the pros over there have no use for running a more efficient operation. God forbid we should get work done faster and make more money in a shorter period of time.
Yeah, I hear ya!
Jon Fife suggested to not waste time attempting to educate those who do not want to learn ?

He suggested educating their competitors instead :eek:
 

Apple Roof Cleaning

Roof Cleaning Instructor
Hey Chris, a guy named David Batts from Rocky Mount, NC called me about getting into roof cleaning. I told him about you and said you would be glad to help him out if he decides to call you.
Yes, have him call Mike.
I am always availiable for one on one question and answer phone calls.
Or better yet, send him this way so he can get our combined experience.
Nothing like taking a newcomer, teaching him, and have him become "one of the guy's here" later ?
 

Apple Roof Cleaning

Roof Cleaning Instructor
FOR MEDIA BLASTING!! Very heavy. Kinda got to haul it over your shoulder like a firehose. I'll take some pics of the guys tomorrow and show you. But from that aspect, all you are saying in regard to hose size is correct....farther we get from the pot, the larger diameter hose we have to have. At 100' w/ 1 1/2", beyond that we begin to drastically lose pressure and probably volume, though that is harder to determine....but without the pressure, it doesn't matter.

Few thoughts:

1) With that volume, why wouldn't guys use that to applicate and wash houses?? Seems easier, might reduce washer use.

2) What are the reasons the guys are still using 3/8" on roofs? You can get more hose on a reel, lighter, maybe "high flow" is too high for some, ......are these the reasons other guys aren't using 5/8" or something?? Just curious, I've seen the fights, but never analyzed.

I guess the reason some continue to use 3/8 hose Jon is because they are religious ?

The "Roof Cleaning God" told em to use it, LOL ....

It certainly defies all logic, real world testing, and computer flow simulations.

BTW, thank you for the advice you gave me on another board!

You are correct in saying you can lead a horse to water, but you can't make him drink.

As you suggested Jon, why waste time trying to educate those who do not want to be educated ?

Educate their competitors instead .....
 
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