slow drip on new plumbing

[Dangerwill]

I just installed my closed loop plumbing and there are 2 slow drip leaks at seals in the pvc.

I did a pretty good job with the red hot blue glue and plumbers tape where glue was not an option (where the pvc threads into my dart pump)

will this plug itself with salt creep or is there something else that I need to do?

Thank you for your help

 

[billdogg]

If it is dripping at a glued joint, you need to cut it out and redo it. Anything else is a bandaid that could (will) eventually fail. If it is dripping at a threaded joint, take it apart, clean the threads - any small burr can cause it to not seal. If it is larger than 1" pvc, I prefer to use ptfe paste (plumbers paste) - just a small amount around the male portion of the treads will spread evenly as you put the two pieces together. If you do use tape, be careful not to use too much - just a couple wraps around will do it.

 

[Dr. Reef]

suggestions above are good and i would follow them yet i have left very very small drip leaks alone and let salt creep fix it but thats just me.

 

[Lain]

I guess I wouldn't want to depend on salt creep to fix the problem. If you did a good job gluing the fitting, it shouldn't leak. I had a leak at my dart outlet, and was able to just tighten down the thread. I used a ball valve union at the inlet and set at the outlet, so I could re-tighten the thread or replace the pump without having to drain the tank.

 

[Dangerwill]

Well I did put unions on both sides of the pump so I took it out this morning. the leak is coming from the threaded joints that go into the pump. I think I am going to give both sides a healthy amount of silicone and then reinstall the works.

Sound good?

 

[uncleof6]

No... Silicone will not bond to the pvc and the leak will return in a very short period of time. The only fix is to cut the leaks out, and redo the joins. This time, use regular pvc cement. Blue hot glue is junk, best relegated to underground sprinkler systems were leaks are not a large concern.

 

[Lain]

Stupid question, but did you teflon the thread in the right direction? Since you have unions for the pump, try tightening the thread a bit more with a wrench. I would stay away from glue on the threaded joints. Also make sure the leak isn't coming from the union.

 

[DHyslop]

One more tip for threaded joints: The threads on sch 40 PVC are often cheaply made, with lines of extra material on the threads where the edges of the molds were (If you ever made plastic models you'll know what I mean). Sometimes it can help to use a sharp razor blade to trim this extra material off. It does take some practice to get the right amount of teflon tape.

Also, put a union fitting everywhere you have a threaded fitting, so you can remove them as necessary.

 

[uncleof6]

Edit:

Use Teflon thread sealant (a paste) on the connections for the pump. It is more reliable than tape, and more mistake proof.

Teflon tape is better suited, along with blue hot glue, to underground sprinkler systems. People have a tendency to use too much tape and over tighten tapered thread connections. However, it is really easy to get the right amount of tape: just read--and comprehend--the instructions, rather than what you read on a forum.

Unions are nice to have, when a piece of equipment needs to be removed. But don't overdo it as I see too many times. They are just another potential leak point.

Lain is right, don't use glue on threaded connections, as my post may have tended to imply. I just glanced at the previous post.

 

[Lain]

I decided to dig up my Dart (stored away for 4 years), and I do recall it was a bit tough to seal the fittings. I ended up using the Teflon paste and a stainless steel strap clamp on both the inlet and outlet. Something like this

. Just tighten up the clamp a bit before you thread in your fitting.

 

[Dangerwill]

Lain,

Did you clamp a flex hose over your inlet/outlet? that had to be a really big diameter hose. My dart has a 2 in inlet and a 1.5 outlet and the largest inner diameter hose I have found is 1.5

 

[Lain]

Just clamp over the inlet and outlet housing. Sometimes when you tighten it too much it would crack the housing. There's a few posting about that happening online. This way you can tighten it down without worrying about that happening. Hopefully the picture of my pump comes through.

 

[Dangerwill]

Oh that is pretty clever. Thanks for the pic, im going to do that.

 

[uncleof6]

That may be clever, but I do not believe my eyes. I run these pumps--MANY of them, I use spa fittings and Teflon thread sealant, and NEVER would I dream of using hose clamps on a Reeflo pump head.

Pipe threads are tapered, and don't need to be tightened much more than hand tight. If you can't get one of these pumps to seal, you are doing something wrong.

The fittings on this pump did not leak, and still don't. (Ignore the gate valve, and the distance to the elbow is just a bit longer ~18".) I don't have the words to describe putting hose clamps on a solid volute.

 

[Lain]

The threads are tapered and over tightening is the cause for a crack volute. Many of us do not do this on a regular bases, and not knowing the exact amount of torque to put on a fitting. Hand tightening is a qualitative torque value, and could result in a crack volute for some. I agree that the clamp is not necessarily needed, but is a lot more forgiving for n00bs like me to install one. If the TS seals and tighten the fitting correctly, the clamp will not have any impact on the volute.

 

[barrettrhoades]

I am with Uncleof6 on this one. The last thing you want is to have any unnecessary stress on a Volute. Use teflon tape, and wrap about 3 times in the direction that you will tighten the fitting. That means that when wrapping a male fitting with the threads facing you and the socket end facing away, wrap in a clockwise manner. Then tighten hand tight, and go no more than 1 turn using a wrench/channel lock. Trust me I do this for a living and you want to do it right the first time, especially if it is on a closed loop, where a failure could mean emptying your tank.

 

[uncleof6]

barrettrhoades, I try not to make a habit of arguing with folks that agree with me, however, three wraps of Teflon tape is too much. If you read the instructions, the instructions indicate only ONE wrap, overlapped by 1/3 IIRC. I haven't read the directions in a while, so I might be off.

Also, for the Reeflo pumps, the instructions call for Teflon Thread Sealant, for both connections to the pump. Nowhere in the instructions, tips, practices, what have you, will you find the use of hose clamps called for, so we are good.

 

[barrettrhoades]

Well it depends on the density of the teflon tape. I usually use low density, where three wraps seems to be just right.
As for thread sealant, I like to use the Spears Blue 75. Not sure if most HD type places would carry that though.

 

[uncleof6]

Well for our reef tanks, I think we had better stick with a Teflon Thread Sealant, rather than a mixture that contains ethylene glycol. (Think anti-freeze and brake fluid.)

 

[Lain]

I can agree that the clamp was probably not needed. In my case, I probably did not tighten the fitting enough. There were also many reports of crack volute due to over tightening (probably due to teflon tape), and one suggestion was to use a hose clamp for added protection. After adding the clamp and re-tightening fittings, no leak or crack volute. I can see how having the clamp would give an extra protection, if that's not the case then please explain why. I am not looking to argue, I just want to hear your point on how the clamp would adversely affect the volute. Which would benefit others who have been given this advice.