Sicce - Trying to Plumb out 1 3/8" -> 1 1/4"

[thecodingart]

I'm actually pretty annoyed with Sicce's unusual threading size on their pump.

My current return line is plumbed for 1 1/4" to get maximum flow out of my waterbox 150.4 setup. It seems the Sicce 7 SDC pump has a thread around it sized for 1 3/8" which is unusual and quite questionable (why ‽).

I'm able to find reducers to go from 1" to 1 1/4" pretty easily -- matching the slip Sicce provides with their 1 3/8" thread, but this isn't what I want. I want to reduce from 1 3/4" to 1 1/4" and retain that flow as much as possible. Better yet, I'd love to use my existing 1 1/4" union attached to the COR 20 I'm removing and replace the end attaching it to my Sicce.

Does anyone know where I could get a threaded reducer fitting my needs?

 

[RedReefer]

Use their slip pvc fitting. I have the same pump and I hard plumbed with slip fitting and unions.

 

[thecodingart]

Use their slip pvc fitting. I have the same pump and I hard plumbed with slip fitting and unions.

Their slip fitting is 1”

 

[RedReefer]

Their slip fitting is 1”

Ok. Go from 1"3/4 to 1" return.

 

[Vivid Creative Aquatics]

If you can connect a 1in pipe, you can immediately step it up to the 1.25in. that small restriction right at the outlet of the pump won't have a huge effect on the overall output of the pump. Most of the output loss comes in the form of friction due to higher velocities inside smaller diameter pipes.

So, if most of your pipe run is 1.25in, then you effetely slow down the flow once it passes that small restriction right at the pump outlet. less friction = more throughput.

The thread is most likely a metric pipe thread, but it may also just be some arbitrary thread size that doesn't conform to any standard (not that uncommon with pumps) .

if you still want to look for a threaded coupling that may fit - then here's a metric pipe thread measurement chart that may help

At a 1 3/8" (1.375in) OD, that's pretty close to the 36mm thread size.

 

[thecodingart]

Ok. Go from 1"3/4 to 1" return.

I mean, this defeats what I was asking to do and what I specifically noted I know I can do…

Not particularly helpful when I literally said:

I'm able to find reducers to go from 1" to 1 1/4" pretty easily -- matching the slip Sicce provides with their 1 3/8" thread, but this isn't what I want.

 

[thecodingart]

If you can connect a 1in pipe, you can immediately step it up to the 1.25in. that small restriction right at the outlet of the pump won't have a huge effect on the overall output of the pump. Most of the output loss comes in the form of friction due to higher velocities inside smaller diameter pipes.

So, if most of your pipe run is 1.25in, then you effetely slow down the flow once it passes that small restriction right at the pump outlet. less friction = more throughput.

The thread is most likely a metric pipe thread, but it may also just be some arbitrary thread size that doesn't conform to any standard (not that uncommon with pumps) .

if you still want to look for a threaded coupling that may fit - then here's a metric pipe thread measurement chart that may help

At a 1 3/8" (1.375in) OD, that's pretty close to the 36mm thread size.

Yeah, I plumbed it with a metric conversion at the actual return which goes to 1”.

The manifold is where I was taking the extra 1/4” of overhead for the 3/4” valves.

Honestly, I’m just going to rip out the manifold and convert it to a direct 1” plumb at this point. The Sicce setup is dumb IMO because 3/8” threading is simply not a standard and you should be able to screw standard sized unions into it directly with 0 overhead.

Sucks that this is so dumb.

Most of my plumbing now-a-days uses dedicated pumps for things and I’ve found little value in manifolds so meh.

 

[Vivid Creative Aquatics]

Yeah, I plumbed it with a metric conversion at the actual return which goes to 1”.

The manifold is where I was taking the extra 1/4” of overhead for the 3/4” valves.

Honestly, I’m just going to rip out the manifold and convert it to a direct 1” plumb at this point. The Sicce setup is dumb IMO because 3/8” threading is simply not a standard and you should be able to screw standard sized unions into it directly with 0 overhead.

Sucks that this is so dumb.

Most of my plumbing now-a-days uses dedicated pumps for things and I’ve found little value in manifolds so meh.

There would still be value in maintaining the 1.25" return pipe - no matter how it start out at the pump (1in or not) - especially if you goal is to maximize throughput.

The amount of throughput you can get out a pump when you over size the return line plumbing is quite surprising .

just to give you an example, i did this on our office 134-gallon cube. We run a cor20 on the return and plumbed the bulk of the return line at 1.25in. I cant crank the pump up past 50% power otherwise it fully overruns the overflow, which is rated at 1800 GPH, the pump itself is rated for 2000 GPH at zero head. So I'm getting pretty close to every G per hour this pump is rated for in terms of output.