Which fittings go here?

SteveG_inDC · Jun 12, 2020

I am connecting a pump with 3/4" FPT inlet, 3/4" MPT outlet to a 1" system. This is for my water mixing station. I figure I'll need unions and ball valves, but I'm staring at websites for PVC fittings and getting super confused.

The bushings I found only reduce from 1" FPT to 3/4" FPT as far as I can tell. Do I need a nipple for the inlet side? Just coming up with a freaking parts list is drivign me crazy, let alone finding the parts all in one place. I've now ordered fittings from aquacave and two local hardware stores and I think I still have the wrong ones.

My biggest problem is knowing when you need slip, when threaded, and how many bushings and adapters. I bought a bunch of slip-slip unions and slip-slip ball valves, but I suspect that was a mistake. I just want to figure out the parts list! Any help is greatly appreciated!

Scoob · Jun 12, 2020

I always use the slip ones, pretty sure that's all I have on the tank.

Billdogg · Jun 12, 2020

And I prefer threaded for any connection that might have to come apart in the future. The problem with slip fittings is that once you use PVC cement on them they are done.

As for what pieces you need - I take what I have to HD/Lowes and stare at all the possibilities until it comes together. But extras! They are all cheap and you WILL need more than you think!!!

SteveG_inDC · Jun 12, 2020

Thanks, but how do you all connect your pumps the system?

Does this make sense?

From Inlet side:
Threaded 3/4" FPT inlet
to 3/4" nipple
to 3/4" to 1" threaded bushing
to 1" threaded union or union ball valve
to 1" threaded-slip adapter
to 1" pipe?

From the outlet side:
Threaded 3/4" MPT outlet
to threaded 3/4" to 1" bushing
to 1" threaded union or union ball valve
to 1" threaded to slip adapter
to 1" pipe

I am assuming that reducing bushings are male on the larger end and female on the smaller end. Not sure if that's right.

bblumberg · Jun 12, 2020

You can get these parts from any Lowes or Home Depot. I like them for most pipe fittings, but buy gate and ball valves from Amazon as the ones they sell at Lowes/Home Depot bind up fairly quickly.

inlet side:
3/4" mpt to 1" slip. Then glue your 1" pipe into this. If you wish, get a 1" true union ball valve and glue this inline so that you can remove pump as needed for cleaning. the configuration is pump, 3/4" mpt x 1" slip, appropriate length of 1" pipe, 1" true union ball valve and then the rest of your plumbing.

outlet side:
3/4" fpt to 1" slip. Then do as above. You may wish to put a small length of silicone tubing inline to isolate vibrations. In this case, add a 1" barb x 1" spigot just after the adapter and another one to the 1" true union ball valve. Get an appropriate length of 1" silicone tubing from BRS or whoever you please. Then the configuration is pump, 3/4" x 1" slip, glue the 1" spigot x 1" barb into that. Glue the other 1" spigot x 1" barb into the true union ball valve (or simply a gate valve since the silicone tubing is easily removable.

SteveG_inDC · Jun 13, 2020

bblumberg said:
You can get these parts from any Lowes or Home Depot. I like them for most pipe fittings, but buy gate and ball valves from Amazon as the ones they sell at Lowes/Home Depot bind up fairly quickly.

inlet side:
3/4" mpt to 1" slip. Then glue your 1" pipe into this. If you wish, get a 1" true union ball valve and glue this inline so that you can remove pump as needed for cleaning. the configuration is pump, 3/4" mpt x 1" slip, appropriate length of 1" pipe, 1" true union ball valve and then the rest of your plumbing.

outlet side:
3/4" fpt to 1" slip. Then do as above. You may wish to put a small length of silicone tubing inline to isolate vibrations. In this case, add a 1" barb x 1" spigot just after the adapter and another one to the 1" true union ball valve. Get an appropriate length of 1" silicone tubing from BRS or whoever you please. Then the configuration is pump, 3/4" x 1" slip, glue the 1" spigot x 1" barb into that. Glue the other 1" spigot x 1" barb into the true union ball valve (or simply a gate valve since the silicone tubing is easily removable.

Perfect, thank you. I had some trouble finding the exact bushings I needed to reduce 1" to 3/4" but found them at pvcfittingsonline.com.

bblumberg · Jun 15, 2020

Great that you found them. I got mine at Lowe's but the main thing is to find them.

SteveG_inDC · Jun 18, 2020

bblumberg said:
You can get these parts from any Lowes or Home Depot. I like them for most pipe fittings, but buy gate and ball valves from Amazon as the ones they sell at Lowes/Home Depot bind up fairly quickly.

inlet side:
3/4" mpt to 1" slip. Then glue your 1" pipe into this. If you wish, get a 1" true union ball valve and glue this inline so that you can remove pump as needed for cleaning. the configuration is pump, 3/4" mpt x 1" slip, appropriate length of 1" pipe, 1" true union ball valve and then the rest of your plumbing.

outlet side:
3/4" fpt to 1" slip. Then do as above. You may wish to put a small length of silicone tubing inline to isolate vibrations. In this case, add a 1" barb x 1" spigot just after the adapter and another one to the 1" true union ball valve. Get an appropriate length of 1" silicone tubing from BRS or whoever you please. Then the configuration is pump, 3/4" x 1" slip, glue the 1" spigot x 1" barb into that. Glue the other 1" spigot x 1" barb into the true union ball valve (or simply a gate valve since the silicone tubing is easily removable.

Thanks for your helpful replies!

I have seen several setups that use a short length of flexible hose between the pump and the hard plumbing to absorb vibrations. I may have done the wrong thing but I bought 25' of spa flex (flexible PVC). I also bought hose barb fittings and clamps. Oops. Just realized that spa flex needs to be glued just like normal rigid PVC.

Should I return the spa flex and buy a short length of 1" hose? I didn't find it in my local hardware store and I hate going to the big box places during COVID. I am sort of intrigued now by the potential uses for flexible PVC, but I don't think it's what I need for this application. Advice appreciated as always.