Chris
Well-Known Member
What if any problems may accure if you used PVC fittings on a CPVC line? Now keep in mind that this is a sewer line with no pressure.
SCH 80 CPVC with SCH 80 PVC Fittins
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Cris, I wasn't aware that they were the same size. I was under the impression that CPVC had a smaller OD then the same size in PVC.
John
John
Chris
Well-Known Member
I will be checking that for sure on Wednesday. I did not know they were not.
I have dealt with similar pipes in the past, Sch 80 CPVC and Sch 80 PVC. In the situation I ran into, I did not dare attempt to glue the two together, as the piping was a 2 1/2" main supply line for a 30 unit apartment building.
But I can say that I have glued literally hundreds of single family home supply mains together (3/4"-1") together using CTS to Sch 40 couplings or bushings, and I can honestly say that I am aware of NO problems arising from that.
So, in the case of a non pressurized sewer connection, I would probably go ahead with the installation. Maybe use a heavy duty CPVC/PVC all purpose glue (I believe that the number is IPS Weld-On 740). Overall, my thought is that you should be fine.
But I can say that I have glued literally hundreds of single family home supply mains together (3/4"-1") together using CTS to Sch 40 couplings or bushings, and I can honestly say that I am aware of NO problems arising from that.
So, in the case of a non pressurized sewer connection, I would probably go ahead with the installation. Maybe use a heavy duty CPVC/PVC all purpose glue (I believe that the number is IPS Weld-On 740). Overall, my thought is that you should be fine.
Oh, and smaller sizes of CPVC is most commonly sold in Copper Tube Size (CTS). It is available in some sizes (maybe all?) in Schedule 80 as well. For those who might not know, Schedule 80 pipe has the same pipe outer size as does standard Schedule 40 pipe, but the wall is thicker to withstand higher pressure. In sizes ABOVE 2", CPVC is only available in Schedule 80.
We have had trouble with Sch 80 CPVC that is not joined to best practice standards when the line is under pressure. Last summer, a fitting that I had put together blew apart under test pressure after an overnight cure. The only problem that we could see was that the 20' length of pipe had a slight bow in it, and therefore the pipe did not completely contact the fitting for a very short distance in two spots. In smaller sizes with thinner pipe walls, such problems are a lot less prevalent.
Sch 80 CPVC pipe and Sch 80 PVC pipe are both the same outside diameter. The fittings look deceptively similar. Another problem that we have run into is PVC Sch 80 fittings getting mixed up with CPVC Sch 80 fittings, and getting installed in boiler rooms. On the top floor of a brand new hotel. The result was epically expensive. So I don't want anyone to get the idea that big pressure pipe is anything to be cavalier with.
We have had trouble with Sch 80 CPVC that is not joined to best practice standards when the line is under pressure. Last summer, a fitting that I had put together blew apart under test pressure after an overnight cure. The only problem that we could see was that the 20' length of pipe had a slight bow in it, and therefore the pipe did not completely contact the fitting for a very short distance in two spots. In smaller sizes with thinner pipe walls, such problems are a lot less prevalent.
Sch 80 CPVC pipe and Sch 80 PVC pipe are both the same outside diameter. The fittings look deceptively similar. Another problem that we have run into is PVC Sch 80 fittings getting mixed up with CPVC Sch 80 fittings, and getting installed in boiler rooms. On the top floor of a brand new hotel. The result was epically expensive. So I don't want anyone to get the idea that big pressure pipe is anything to be cavalier with.
