Sealant and techniques

[SteveMitty79]

I am about to thread sch 80 1-1/4" PVC and attached galvanized steel couplings on one end in prep for installing my pump.

What sealant would you use if any and what tightening technique works for you?

Thanks.

 

[Reach4]

I suggest stainless or brass couplings. You don't want to add any new galvanized to your home water system. I would remove any galvanized if handy, such as if the existing couplers were galvanized. On the other hand, if the water is just for the livestock or plants, that might be different. The turkeys will tolerate the taste and will not be offended by staining of plumbing or laundry.

You might want to get the stainless coupler(s) on order. On https://terrylove.com/forums/index....about-pvc-well-pipe-color-and-suppliers.60972 , a thread you were in, post #8 craigpump suggested Rectorseal. Rectorseal No. 5 is the classic. RectorSeal® T Plus 2 is also good, and I might go that route. I have used No.5, but I have not done well drop pipes or outside couplings. http://www.rectorseal.com/index.php/pipe-thread-sealants/

 

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[Valveman]

With metal couplings on sch 80 PVC pipe I don't use any sealant or pipe dope. Just tighten with a wrench until you hear it pop 2 or 3 times and your good. I think the threads are less likely to come unscrewed from pump starting torque if I don't use any pipe dope.

 

[SteveMitty79]

With metal couplings on sch 80 PVC pipe I don't use any sealant or pipe dope. Just tighten with a wrench until you hear it pop 2 or 3 times and your good. I think the threads are less likely to come unscrewed from pump starting torque if I don't use any pipe dope.

Since I'm not going to use a torque arrestor, this idea sounds favorable. Any more?

 

[Valveman]

I like double jacketed wire taped every 10' or 20', and a CSV to eliminate the cycling, which further eliminates the need for torque arrestors.

 

[Craigpump]

I was on a call Monday to a job that I installed 27 years ago with galv couplings on sch 80. It's still working with no leaks or issues. Today I'd use sch 120 pvc or maybe stainless.

As for sealant, I like Rector Seal or maybe a good quality Teflon paste.

That job I installed 27 years ago is still on the original Goulds 3/4-7 3 wire pump using single insulated wire, a large tank (Goulds v260) and torque arrestors. Sure it's getting tired, but look at the water it's delivered over the years......

 

[Valveman]

With a 3/4-7 GPM pump I am guessing little to no irrigation, which would be maybe 300 gpd for 27 years, or close to 3 million gallons. That tank is about 3 times larger than what pump manufacturers would say is a "properly sized tank", which I am sure is one reason the pump lasted so long. That is also the way I liked to size tanks before using CSV's, if I could get the customer to spring for the larger tank(s).

In my area a 1.5HP or 2HP- 20 GPM pump is normal, with lots of mis-matched irrigation. That could be upwards of 12 to 15 million gallons in 27 years. You can't put in a large enough tank(s) to keep cycling on/off from destroying the pump prematurely, and half a dozen torque arrestors wouldn't be enough to keep it from whipping the wire. I have many of these systems with CSV's, a small tank, and no torque arrestors that are still working after 23+ years. I don't know how much longer they will last. But if a CSV made these systems last that long, they would certainly make a 3/4-7 with no irrigation last a long time as well.

Additionally with the really large tank the shower pressure would be descending from 60 to 40 PSI a lot of the time, while the people with a CSV and small tank are enjoying a constant 50 PSI all the time. It doesn't sound like much difference but a constant 50 PSI is much better shower pressure than when pressure is continually descending coming out of a pressure tank. And it is much easier to make sprinklers hit the target and overlap as they should with a constant 50 PSI compared to pressure continually changing from 60 to 40, 40 to 60 over and over.

But good job, 27 years is an excellent run for any old pressure tank only type system.