Garden Soaker Hose / Pressure Regulator?

[Quattro Pete]

I need to get some soaker hoses for the flower/shrub bed. To go with that, am I supposed to also install a water pressure regulator between the tap and the soaker hose?

I've seen most soaker hoses have a restrictor at the beginning of the hose. It basically looks like a washer with a small hole in the middle. Wouldn't this in itself act as a pressure regulator or do I still need to install a separate regulator?

 

[Food Scientist]

I have using the same soaker hose for three years and never used a pressure regulator with about 40 psi max water pressure. Mine has a restrictor but I think that is to block debris that may come through the line so it doesn't plug up the small holes in the hose. Also if the line got smaller with the same output of volume, then the pressure would actually go down because the velocity of the water increased. Bernoulli's Principle.

 

[Quattro Pete]

This doc I found says that the restrictor/ring inside the hose works just like an external pressure regulator:
http://yardener.com/YardenersToolshedofP...singASoakerHose

But then another pamphlet from Orbit says to ALWAYS use a pressure regulator to ensure pressure does not exceed 25 PSI.

 

[Food Scientist]

Yep, I see that. Something the article doesn't clearly define is what happens if you exceed the 10 psi optimal pressure. My main concern is that there would too much pressure drop across the hose (depending on length of course) because of friction and the water you are losing along the way, which means 10 psi may not be enough. The best way to tell is to see the distribution of your water in the ground.

In a way he contradicts himself because he talks about turning the faucet to just a 1/4 to 1/2 turn to reduce the water pressure. The pressure remains the same but the volume is reduced. If that is his mode of thinking, then I would reduce volume of water and not pressure.

Like I said earlier, I have been using the same soaker hose for 3 years now and it is 100 feet long and is just the cheapie stuff from Walmart. No problems as of yet.

 

[Quattro Pete]

Thanks. I'll head out to Walmart later today to see what I can find.

 

[doitmyself]

You can reduce hose pressure by throttling back the valve, but I don't know how to explain the principle.

You can also buy cheap, pre set pressure reduction valves in the drip irrigation section of the big box stores. They cost under $10.

Finally, be aware that a reduced pressure/back flow situation could result in contaminated water in the gunky hose being drawn into your home water supply, depending on how your plumbing is set up. Most of us don't worry about this rare occurence.

 

[Quattro Pete]

Well, I went to three different stores (Walmart, HomeDepot, and Lowes) and none of them had the pressure reduction/regulator valves. As a matter of fact, they all looked at me like I was from Mars. I guess the whole pressure thing isn't as big of a deal as some make it out to be. Otherwise, these regulators would be sitting on every shelf.

Same story with the back flow preventer valves.

 

[Quattro Pete]

Also, why don't any stores carry female-to-female hose connectors??? Ugh...

 

[HTSS_TR]

"female-to-female hose connector" is so gay !

 

[doitmyself]

Originally Posted By: Quattro Pete
Well, I went to three different stores (Walmart, HomeDepot, and Lowes) and none of them had the pressure reduction/regulator valves. As a matter of fact, they all looked at me like I was from Mars. I guess the whole pressure thing isn't as big of a deal as some make it out to be. Otherwise, these regulators would be sitting on every shelf.

Same story with the back flow preventer valves.


Hmmmmmm: http://www.homedepot.com/Outdoors-Garden...p;storeId=10051
http://www.lowes.com/pd_191774-1029-MLD-25PR_4294724046_4294937087_?productId=1054541&Ns=p_product_qty_sales_dollar|1&pl=1&currentURL=%2Fpl_Drip%2BIrrigation_4294724046_4294937087_%3FNs%3Dp_product_qty_sales_dollar|1&facetInfo=
Bought some several years ago.....maybe only mail order now

and.... http://www.homedepot.com/webapp/catalog/...tgry=SEARCH+ALL

although, these don't quite meet code for a true RPZ (backflow preventer).

 

[Food Scientist]

Originally Posted By: doitmyself
You can reduce hose pressure by throttling back the valve, but I don't know how to explain the principle.


No you can't. The pressure is the same at all times, so turning the valve back only reduces volume not pressure. In a fluid mechanics class I took in college, if a pump is oversized and is pumping too much, the fastest way to correct this is to install a valve to regulate volume, but maintain pressure.

It may seem like you are reducing pressure because the stream of water is not coming out as hard, but that is all related to volume. Check out Bernoulli's Principle.

 

[doitmyself]

Well, the pressure gauges on my irrigation systems must be wrong, then.

I don't understand how your principle would apply to a system like a soaker hose that is open vs. closed loop.

As you reduce the input water valve opening, the soaker hose "opening" remains the same. At a certain point, the water leaving the hose will be greater than what is going in and the pressure will drop.

 

[Quattro Pete]

Originally Posted By: doitmyself
Hmmmmmm: http://www.homedepot.com/Outdoors-Garden...p;storeId=10051
http://www.lowes.com/pd_191774-1029-MLD-25PR_4294724046_4294937087_?productId=1054541&Ns=p_product_qty_sales_dollar|1&pl=1&currentURL=%2Fpl_Drip%2BIrrigation_4294724046_4294937087_%3FNs%3Dp_product_qty_sales_dollar|1&facetInfo=
Bought some several years ago.....maybe only mail order now

and.... http://www.homedepot.com/webapp/catalog/...tgry=SEARCH+ALL

although, these don't quite meet code for a true RPZ (backflow preventer).

Thanks for finding these. I will print these out and try my luck again. If nothing, I'll just order from Amazon.

 

[Food Scientist]

Originally Posted By: doitmyself
Well, the pressure gauges on my irrigation systems must be wrong, then.

I don't understand how your principle would apply to a system like a soaker hose that is open vs. closed loop.

As you reduce the input water valve opening, the soaker hose "opening" remains the same. At a certain point, the water leaving the hose will be greater than what is going in and the pressure will drop.


Its not my principle, but it applies to any system, closed or open. One of the hardest problems we ever had was to determine pressure drop across a pipe with openings in it and determine the size of each hole to maintain the same volume of water output from each hole (hint it gets bigger the farther you get away).

Your pressure drop is related to less water volume because the size of your hose is not changing. Also flow in has to equal flow out, the pressure drop is related to friction and loss of water as it travels through your soaker hose or any hose.