Questions regarding Fernco Fittings

[akmacs]

Hi again,

I am in the process of moving my closet flange for my new toto drake and am reconnecting my waste line and the vent. I need a fernco fitting for the vent line (3" abs to 3" abs) and the connection will be concealed under the subfloor. There is about a quarter inch gap between the pipe ends (as currently cut and dry fitted) and they are lined up straight. The local plumbing shop gave me two options to connect (I bought both). One is a fernco 1056-33 and the other is a fernco proflex 3005-33 (pics below). I like the proflex because it is banded with sheetmetal and is the stronger of the two, but it also has a rubber stop which would make it unusable for this application unless I cut out that lip. The 1056 does not have a rubber stop in it but is not as strong. I doubt there would ever be much movement barring an earthquake so maybe the proflex is overkill?

I guess my question is would you recommend one versus the other and would have any issue utilizing one in a concealed location?

I must say, plumbing is a very humbling experience so far, thanks for all that you all do, and also thanks
for your professional help in advance!

 

[Gary Swart]

The neoprene sleeve is not to be used above ground. It has to be buried for the very reason you have noted. Soil all around it will provide strength and keep the joint ridged. I have some concern about your comment that you have things "dry fitted". If you mean you have inserted PVC pipe into fittings without solvent welding, that will present one of two problems. If you have jammed the pipe into the fittings, you may fit it impossible to separate them. If you have just loosely assemble the joints, when you apply the solvent and push the pieces together, the pipe will go considerably deeper into the fittings, and you will be short. You really have to cut and fit PVC as you go using a tape measure and allow for the space inside the fittings especially when you are working in the middle of a section.

 

[Sponsor]

 

[akmacs]

Hi Gary,

I just fit everything together pre-gluing just to get it at the right length, that is a good tip about the glue allowing the fittings to fit together easier. It is a pain but I have been able to pull the fittings back out. I will using abs, not pvc and I actually bought some extra couplers just to figure out the amount of pipe cement to use so I don't puddle it on the inside.

As far as the two fittings go, you say the the sleeve minus the banding should not be used?

 

[Gary Swart]

The same principles apply to ABS as PVC. Assembling with the "glue" is easier, but that's not the main concern. When you dry fit a joint, the pipe does not bottom out in the fitting. There may be as much as 1/4" space between the end of the pipe and the bottom of the fitting even though it seems a tight fit. When the solvent is applied and the final connection is made, the pipe will bottom out in the fitting so your pipe length will be 1/4" or so short. After several connections, you can be way short. You understood my point correctly about not using the plain sleeve in this application.

 

[akmacs]

Gary, do you think carefully cutting away the rubber stop with a razor knife inside the banded coupler would be ok? I need to be able to slide it up to cover the joint, I could mark the pipe with a marker to make sure I have an equal amount of pipe in each end before tightening.

 

[Gary Swart]

I have not done this, and I can't recall the question ever being asked, but my reasoning is that it would not hurt anything to trim the center stop. Keep in mind, I'm not a pro, and I have been know to err.

 

[hj]

You slide the metal band onto the pipe, then place the rubber sleeve on one of the pipes. Roll the "free" end of the rubber band back over the other end, then put the pipe in place. "Pop" the rolled over end onto the pipe, slide the metal band back into position, then tighten the bolts.

 

[Nate R]

You slide the metal band onto the pipe, then place the rubber sleeve on one of the pipes. Roll the "free" end of the rubber band back over the other end, then put the pipe in place. "Pop" the rolled over end onto the pipe, slide the metal band back into position, then tighten the bolts.

Wow, wish I had done it that way when I put one in on my main stack. I had about 1/4" gap, and I was trying to slide the coupliing down the pipe, pull the connecting pipe in place, then slide it back up until the inner rubber ring was between the two. This was extremely difficult to do without leaks as I hadn't cleaned the cast enough, and little flecks would get stuck and cause it to leak. I was using a soapy water solution to try and make it more slippery so it would work, etc.

I should've stopped then and asked for advice here on that situation. Ahh well, it worked out in the end, and now I know better if I ever need to do it on another pipe in the future.

 

[Gary Swart]

Skill and experience wins again!

 

[akmacs]

HJ, just a quick thanks, thats gonna do the trick.

 

[hj]

quote; Skill and experience wins again!

True, but then you lose all the fun and frustration of fighting the job, banging or pinching your fingers, and doing it over a second time.