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v1rtu0s1ty
04-25-2007, 10:34 PM
I'm back guys. I have downloaded the document from Rain Bird where we draw our property. I've finished drawing it. However, there is another form that I need to fill out. There was one item there that I don't know what to write. It is the flow test. The unit is in GPM, gallons per minute. How do I conduct the test to get an accurate GPM reading?

Thanks!

hj
04-26-2007, 06:44 AM
Unless you already have the connection opening in place, you will not get a true reading, but use a five gallon bucket and see how long it takes to fill it. Then extrapolate that figure into gallons per minute.

jimbo
04-26-2007, 06:52 AM
The home stores usually sell a Toro combo pressure and flow test jig:
http://www.toro.com/sprinklers/irrmisc/pressuregauges/53351-gauge.pdf#page=1

v1rtu0s1ty
04-26-2007, 08:56 AM
Rainbird told me this but I think it's not correct.

Fill up a 5 gallon bucket and time it. Then the number of seconds I will get should be multiplied to 60. Then the product, divide it by 5.

I don't think it's correct. Even if I use 40 seconds to fill up a 5 gallon bucket, we will get 480. And they told me that 480 is the gallons per minute. LOL. I can now then provide water to our fire department. LOL.

Gary Swart
04-26-2007, 09:04 AM
I don't understand their formula either. Here's what I come up with. You filled the 5 gallon bucket in 40 seconds. 40 seconds is 2/3 of one minute. 5 divided by 2/3 is 7-1/2 gallons per minute.

v1rtu0s1ty
04-26-2007, 09:31 AM
I think that looks better. Here is the final formula

GPM = Ngallons / (seconds / 60)

example for a 2 gallon bucket, and it took 5 seconds to fill it up

GPM = 2 gallons / (5 secs/60)
GPM = 2 gallons / .08333
GPM = 24

in our earlier example, 40 secs for a 5 gallon bucket

GPM = 5 gallons / (40 secs/60)
GPM = 5 gallons / .67
GPM = 7.5

in my real test, I went outside and hooked up a hose, it took 30 secs to fill up a 5 gallon bucket

GPM = 5 gallons / (30 secs/60)
GPM = 5 gallons / .5
GPM = 10 gallons

what do you think guys about my GPM? Is it low?

and the PSI based from the tool I bought says 55 psi.

Do I have good data for me to continue my sprinkler system wish or dream? :)

speedbump
04-26-2007, 09:56 AM
Getting the flow from a hose bibb will probably not give you the figure your looking for. Most water hookups are either 5/8" or 3/4". A lot more water will flow from the larger pipe than it will through a hose bibb which is usually piped with 1/2" or smaller. Where your sprinklers are going to be tee'd in is where you need to do the bucket test.

v1rtu0s1ty
04-26-2007, 10:06 AM
Getting the flow from a hose bibb will probably not give you the figure your looking for. Most water hookups are either 5/8" or 3/4". A lot more water will flow from the larger pipe than it will through a hose bibb which is usually piped with 1/2" or smaller. Where your sprinklers are going to be tee'd in is where you need to do the bucket test.

Ah, I was actually thinking of that last night. I was telling myself that the system will not be connected to the outside faucet. But I'm thinking of hooking up new copper pipes. Unfortunately, I don't have those pipes yet. So folks, what diameter of pipe are your recommendation from the inside which is in my basement? Do I just need one new 3/4" or 5/8" copper pipe going to the device that does the zoning?

If that is the case, how do I properly measure the the GPM then?

I'm worried now with RainBird since they already failed with the formula. Or is it just because those are just sales people?

speedbump
04-26-2007, 10:13 AM
Wherever your going to tee into your existing water pipe is where you should do the test. You will have to shut the water off at the meter to make the tap on the main line. Then do the bucket test from that new line which can have a valve right at the tee. You should also have a gauge in that line so you can see how any gallons per minute you get at around 40 lbs. That is what the sprinklers are going to want to work with.

bob...

v1rtu0s1ty
04-26-2007, 10:54 AM
Here is a picture of the pipe that is coming from the city. It is in the basement. It's the one on the right. It's a 1" pipe. Then at the bottom, it connects to a bigger pipe that is connected to the wall(from city).

http://restricted.dyndns.org/vsr_sf_complete_virgin_setup.jpg

I'm wondering why the psi gauge that I bought is reading 55 to 57 when I connected it to the outside faucet. Then if you look at the other pipe which is on the left(fire sprinkler pipe 2"), it has a gauge too at the bottom but not shown. The reading is 78 psi. From what I know, psi should be the same for all right?

Is it possible to calculate the GPM if we have the PSI value?

Gary Swart
04-26-2007, 04:13 PM
You will have to take the gpm available into consideration when designing the system so you don't overload your zones. You also need to consider friction loss through the pipes. It would be my suggestion to contact an irrigation supply house. They often will design a system for you at no cost as long as you buy all of your pipe, fittings, sprinklers, and other components from them. They know what size pipes you need, when to reduce to a smaller size, and the best sprinklers for each zone. You will need to have a good scale drawing of your property showing where everything is, have the meter size, size of the pipe coming out of the meter and how far it will run to the manifold, and static water pressure. Of course, they will be more than happy to do a complete installation for you, but that isn't a freebie.

v1rtu0s1ty
04-26-2007, 06:53 PM
You will have to take the gpm available into consideration when designing the system so you don't overload your zones. You also need to consider friction loss through the pipes. It would be my suggestion to contact an irrigation supply house. They often will design a system for you at no cost as long as you buy all of your pipe, fittings, sprinklers, and other components from them. They know what size pipes you need, when to reduce to a smaller size, and the best sprinklers for each zone. You will need to have a good scale drawing of your property showing where everything is, have the meter size, size of the pipe coming out of the meter and how far it will run to the manifold, and static water pressure. Of course, they will be more than happy to do a complete installation for you, but that isn't a freebie.

That's why I started with asking how to get the GPM because it's one of the question in the RainBird form. I was about to send the form and drawing today to Rainbird but I learned from folks here that I should not use the GPM reading I got today via which I got when I used the faucet outside the house.

Now, I'm stucked. I don't know what to do. I don't have any faucet in the 1" pipe from the picture above.

v1rtu0s1ty
04-26-2007, 07:00 PM
Wherever your going to tee into your existing water pipe is where you should do the test. You will have to shut the water off at the meter to make the tap on the main line. Then do the bucket test from that new line which can have a valve right at the tee. You should also have a gauge in that line so you can see how any gallons per minute you get at around 40 lbs. That is what the sprinklers are going to want to work with.

bob...

Hi speedbump,

Can you explain to me what valve I should be getting? Is the picture below is what I should be getting? And do I connect a faucet to this valve so I can conduct testing?

http://www.ultimatewasher.com/images/accessories/ball-valve-stainless-big.jpg

What about the gauge? Is the connection suppose to be like this(from left to right)

my 1" pipe -> T -> valve -> gauge -> pipe going to whatever

v1rtu0s1ty
04-26-2007, 08:40 PM
Gary, your suggestion was also the suggestion last year given to me. However, I got so stucked in projects in the office. I didn't have much time. I also remember someone from this forum told me that once I receive the design, post it so that they can look at it and make changes/corrections. However, like what I said earlier, I'm stuck with some variables. Until I get those numbers, that's the only time I will be able to send this drawing.

I hope you guys can advice as to what I should do first.

Any help would be greatly appreciated! :)

Cass
04-27-2007, 03:49 AM
Is there a check valve on the sprinkler system?

Here is a picture of the pipe that is coming from the city. It is in the basement. It's the one on the right. It's a 1" pipe. Then at the bottom, it connects to a bigger pipe that is connected to the wall(from city).

http://restricted.dyndns.org/vsr_sf_complete_virgin_setup.jpg

I'm wondering why the psi gauge that I bought is reading 55 to 57 when I connected it to the outside faucet. Then if you look at the other pipe which is on the left(fire sprinkler pipe 2"), it has a gauge too at the bottom but not shown. The reading is 78 psi. From what I know, psi should be the same for all right?

Is it possible to calculate the GPM if we have the PSI value?

speedbump
04-27-2007, 05:50 AM
It would be 1" pipe, tee, gauge valve then add some pipe temporarilly of the same size or bigger to where ever your going to do the bucket test. You will want to run the water with the valve closed enough to see 40 psi on a (new gauge), then see how long it takes to fill the 5 gal bucket. This is the amount of water your sprinklers will have available if your city water is constant.

bob...

v1rtu0s1ty
04-27-2007, 12:59 PM
when I got to Home Depot/Lowes or ******* tonight, what should I look for, do I just say water gauge, gauge valve? How does it look like?

searching images.google.com with "gauge valve"gave me this:

searching "water gauge" gave me this:

v1rtu0s1ty
04-27-2007, 01:01 PM
cass,

I'm sorry, I got confused when you said sprinklers. I don't have any sprinkler system for my lawn. But I have fire sprinkler system.

Please let me know what you need.

Thanks,

Ronneil

speedbump
04-28-2007, 06:08 AM
I recommend a better gauge than you get at HD or the others.

Look at the Gauge on this page. This is what they look like.

Gauge page. (http://pumpsandtanks.com/accessories.htm)

bob...

v1rtu0s1ty
04-28-2007, 07:32 AM
is this the exact one?

If that is the one you were referring to, how come the tube where the thread is is thin? They are just 1/4". How will I connect it to the Tee? I'm sorry, once I see how it looks like, it will be easier for me to understand.

Thanks again for bearing with me.

speedbump
04-28-2007, 07:42 AM
That one is on my shopping cart. I'm not sure how I got a 200# gauge there, it should be a 100# gauge. Maybe it was the best image I could find at the time. Anyway, that is what they look like. You can get 1/4" or 1/8", they are all 100 or 60 psi max. You will have to put in another tee after the main tee and bush the opening down to 1/4" to install the gauge.

I can't think of any images that I have that would make it easier.

bob...

speedbump
04-28-2007, 08:03 AM
This might help.

v1rtu0s1ty
04-28-2007, 08:06 AM
It does help a lot. :)

So, is that the online store you are recommending to me? Don't HD, Lowes, Sears or Ace Hardware sell it?

Looking at the drawing again, to the right of the pipe, you mentioned valve. Looks like valve is controllable?

Then can you post me a picture link of the valve that will be used to backpressure please? :)

speedbump
04-28-2007, 08:18 AM
Just for the test your doing, you can buy one just about anywhere. Most of them are cheap. The one I sell is cheap for that matter. They are mostly for us to set up a system then we don't need them anymore. If you want to depend on it for several years, don't buy mine or one from any store. Good gauges start at around \$15.00. Mine is overpriced at \$2.65. If I need a good gauge, I order one at a time because most people don't want to spend that much.

bob...

v1rtu0s1ty
04-28-2007, 10:02 AM
oh, so that means, once I get all the readings, we don't need them anymore? Or is it really required to have one once I get the lawn sprinkler system up and running?

If we just need it for testing, I can just buy at HD or Lowes for now. Then once I'm ready, I can buy a better one like what you said.

But I had a question earlier and I think it was not addressed. You mentioned valve on the drawing. Can you please tell me how it looks like?

speedbump
04-30-2007, 05:19 AM
Sure, for what your doing any old gauge will do.

The valve you posted a picture of will work. Or you can get a gate valve which has a spoked handle and turns several times between open and closed. It might be easier to get the desired pressure with that than the quarter turn ball valve.

bob...

v1rtu0s1ty
05-02-2007, 06:38 AM
Found a picture of gate valve using images.google.com. Which one?

http://www.ball-valve-manufacturer.com/images/product-b/GT-200.jpg

or this one

http://www.pokfire.com/images/product/valves/gated.jpg

And also, if you look at my earlier pictures specifically my vertical 1" copper pipe, will there be any difference in pressure if putting the new pipe closer to the lower part of the existing pipe since it will be closer to the city? The new size of pipe will be the same though.

Thanks! :)

speedbump
05-02-2007, 06:57 AM
I would go with valve #1.

I don't think the length of the pipe will make any difference.

bob...

v1rtu0s1ty
05-02-2007, 05:44 PM
Cool! Sorry, I have so many questions. :)

How much should I remove from the 1" vertical pipe so I can insert the Tee?

Thanks again!

speedbump
05-03-2007, 06:10 AM
You would take out the same amount of copper as there is space in the tee between where both pipes will butt inside the tee.

bob...

v1rtu0s1ty
05-09-2007, 06:52 AM
I would go with valve #1.

I don't think the length of the pipe will make any difference.

bob...

I was at my basement again today. I looked at the 1" and where it leads to. The 1" pipe goes near side of the backyard. Can I just hook from there?

v1rtu0s1ty
05-09-2007, 06:58 AM
You would take out the same amount of copper as there is space in the tee between where both pipes will butt inside the tee.

bob...

Hi bob,

I'm sorry but I still couldn't visualize this out. Do you have pic?

Thanks,

ron

speedbump
05-09-2007, 07:34 AM
I don't have any pics I can think of. Just think of it this way. If you have a tee that has 1-1/4" between the two female inserts on the tee, you have to cut out 1-1/4" of pipe to make room for the tee. You will also have to be able to move the pipe up or down enough to put the second piece of pipe into the tee's insert. It can be inserted in the 1" pipe anywhere you can get to it.

bob...

v1rtu0s1ty
05-09-2007, 09:41 AM
Ah, that helps a lot. :)

By the way, I encountered an issue when I sweated my friend's pipe on his outside faucet. The 90 degrees elbow was so close to the joist. I had an impression that I got a complete lead around the hole. Last week, he used that faucet. He found out that water was squirting from the top part of the elbow. I don't want that to happen in this project that I'll be doing. So, is it because I didn't put enough flux?

Please let me know if my steps are correct.

1. I used an emery cloth. Actually I have a metal rounded brush that I insert the copper pipe. I make sure that it's very clean.

2. I apply flux on the cleaned copper pipe and on the cleaned coupling or cleaned elbow or whatever.

3. I join the two together and twist it so flux gets spread

4. I heat it and apply lead

speedbump
05-09-2007, 10:09 AM

You mean solder I hope. The big trick is to get it super clean, flux both halves. Put heat on one side and the solder on the other side. When it flows, your done.

bob...

v1rtu0s1ty
05-09-2007, 10:42 AM