Please Educate me on HDPE/Poly Pipe

[sjvicker]

I'm working on setting up my water system and am planning to pump up to a cistern with a solar pump then gravity feed back down to the shop/house with max pressure being around 60psi. Can someone point me in the right direction on which HDPE/poly pipe I should be using?

This stuff at Home Depot seems like its intended for potable water use in buried applications.

Advanced Drainage Systems 1-1/4 in. x 300 ft. IPS 100 PSI NSF Poly Pipe X2-125100300 - The Home Depot

The Advanced Drainage Systems 1-1/4 in. x 300 ft. IPS 100 PSI NSF Poly Pipe features flexible construction for convenient installation. This withstands weather and human elements. It is designed for long

www.homedepot.com

This stuff is rated for higher PSI so I'm assuming its more robust but otherwise is also for potable water and buried applications

1-1/4" IPS SDR11 PE4710 Black Hdpe Pipe 500' Coil

Hdpe Supply is your number one source for Hdpe Fittings, Hdpe Pipe, and Fusion Equipment. We sell polyethylene pipe, **** fittings, socket fittings, electrofusion fittings, and fusion equipment.

hdpesupply.com

The 1.25" home depot stuff comes in at around $0.75 per ft and the HDPE supply pipe is $1.30 per ft before shipping. I was also quoted $1.53/ft for poly pipe from a local supply shop. I'm going to have about 1000' of 1" and 1000' of 1.25" so a small cost difference adds up quick. Is there any reason why the HD pipe would be inadequate? It seems like it meets the criteria needed but I'm apprehensive about it due to the cost being so much less than the other types.

Thanks

 

[rlitman]

The cheap thin wall 100PSI stuff is designed for irrigation, and is not recommended for continuous pressurization (e.g. an irrigation main line).

 

[Bretny]

There are differences in this type of pipes ID. Even though they say 1.25in they may be different. Google it.

I have 400ft of 1in black poly laying out on the ground for the same type of system your describing. A gravity feed cistern. It runs the water system of a offgrid camping property. Animal like to chew black poly along with the PVC valves I have in the system. I assume it's either move or squirls chewing it.

With a gravity system if you keep your pipe diameter large you dont need as much head pressure as you think. Mine is only about 30ft above my shower head and worst very well. Its 1in poly to 3/4in garden hose.

 

[Bretny]

Reading your post again..are you pumping up with a 1in and gravety down with 1.25in?

Is there any way you can use the same pipe for each purpose? The single pipe could be the supply to and from the cistern. If not can you use a small 1/2in pipe to fill the cistern?

 

[Innovate1]

Plastic pipe takes several forms/sizes. There is CTS (copper tube size) pipe that takes compression fittings. There are also IPS (iron pipe size) that takes insert fittings such as what you listed. The barb fitting pipe comes in a couple pressure ratings, 100 PSI and 160 PSI, I think. I would go for the 160 PSI barb fitting pipe as it isn't too much more cost.

I may have a few details wrong as I just wrote that from memory so hopefully others will correct any mistakes.

 

[sjvicker]

Reading your post again..are you pumping up with a 1in and gravety down with 1.25in?

Is there any way you can use the same pipe for each purpose? The single pipe could be the supply to and from the cistern. If not can you use a small 1/2in pipe to fill the cistern?

That's a great idea! I hadn't thought about that. I'll have a float valve in the tank that's mounted to the inlet so in this case I think if I just T'ed the inlet and outlet of the tank together it would work as intended as long as the T is at the same height as the outlet. The pump shouldn't really care and has a check valve on it.

 

[sjvicker]

Plastic pipe takes several forms/sizes. There is CTS (copper tube size) pipe that takes compression fittings. There are also IPS (iron pipe size) that takes insert fittings such as what you listed. The barb fitting pipe comes in a couple pressure ratings, 100 PSI and 160 PSI, I think. I would go for the 160 PSI barb fitting pipe as it isn't too much more cost.

I may have a few details wrong as I just wrote that from memory so hopefully others will correct any mistakes.

Thanks for the explainer on the pipe sizes. It makes sense why I've come across a few cases in my search where a barb fitting doesn't seem to work right with Poly pipe. With IPS the exterior dimension governs so a lower PSI pipe will have thinner wall and fit looser on a barb fitting.

I'm planning to use compression fittings instead of barbs. It's probably not logical but I just dont trust worm drive clamps, even if there is 2 of them. https://hdpesupply.com/1-1-4-ips-compression-coupling/

 

[quad shop]

This is a civil contractors approach so a little more expensive but bullet proof. I would use cts (much easer to find and adapt to if ever needed) pipe with brass compression couplers like these https://www.plumbersstock.com/ttcup...&utm_medium=cpc&scid=scbplp7722&sc_intid=7722 . They have an internal stiffener and are less prone to breaking. Just make sure you tighten all the way to the shoulder.

 

[rlitman]

This is a civil contractors approach so a little more expensive but bullet proof. I would use cts (much easer to find and adapt to if ever needed) pipe with brass compression couplers like these https://www.plumbersstock.com/ttcup...&utm_medium=cpc&scid=scbplp7722&sc_intid=7722 . They have an internal stiffener and are less prone to breaking. Just make sure you tighten all the way to the shoulder.

That's for the good 200PSI poly that's used in water mains.

 

[quad shop]

Correct.... I said civil contractor. There is nothing worse than being without water or fixing a water break. Hell even my irrigation "Mains" are plumbed this way.

 

[Bretny]

That's a great idea! I hadn't thought about that. I'll have a float valve in the tank that's mounted to the inlet so in this case I think if I just T'ed the inlet and outlet of the tank together it would work as intended as long as the T is at the same height as the outlet. The pump shouldn't really care and has a check valve on it.

With a float valve in the tank I assume your pump has a high pressure shutoff?

With that setup you may need a pair of check valves at the tank. One at the float valve to let the water in and one at the bottom of the tank/outlet to let the water out.

 

[sjvicker]

With a float valve in the tank I assume your pump has a high pressure shutoff?

With that setup you may need a pair of check valves at the tank. One at the float valve to let the water in and one at the bottom of the tank/outlet to let the water out.

Yeah, I caught that yesterday and got a check valve on order. Now water can only flow in to the top of the tank and that's where the float valve is and it can only flow out through the bottom of the tank.

I ordered a system from RPS and it includes a reverse pressure switch that will tell the solar charge controller to shut off the pump when full.