Smaller pipes in and out the pump

[Emiliano]

Hello all. I have an existential question on my pump's plumbing

Is there any reason to have smaller pipes connecting the pump.

There used to be a single speed pump that I replaced by a VS, maybe restricting flow for some reason? Restricting the flow for the heater?

Should I keep it now that the VS Pump is in place?

 

[HermanTX]

You probably will not be running the VS at full speed that often so having 1.5” pipe (that what it looks like in photo), will not be a restriction. With a SWCG are you running 24hrs pump at somewhere between 1200 and 2000 rpm?
Is that flexible pipe I see for a drain?

 

[Emiliano]

You probably will not be running the VS at full speed that often so having 1.5” pipe (that what it looks like in photo), will not be a restriction. With a SWCG are you running 24hrs pump at somewhere between 1200 and 2000 rpm?
Is that flexible pipe I see for a drain?

Yes, that's what I thought, there is not that much friction at lower water speeds. I run the pump at 2000 rpm for 12 hours and I get 30gpm at that speed.

The pipes are effectively 1.5 " into 2".

On the other hand, if someone put those smaller sections as a protection, if I happen to run the pump at full speed the protection will still be in place

No flexible pipe , that's a rain spout extension that happened to be laying there before going into the garbage.

 

[SJPoe]

On the other hand, if someone put those smaller sections as a protection,

I would guess the 'main' pipes are 2", and the old pump was 1.5, so they put a reducer in to marry-up to the pump.

Then when the pump was replaced, rather than cut the pipe at the 2" part and just put a coupler on and then carry 2" to the pump, they cut the 1.5", realized the 2" from the pump wasn't 1.5", and then just threw a reducer on to connect to the existing bit of 1.5" - maybe they had a 2"-1.5" reducer in the truck, and not a 2" coupler...

My OCD would make me replace the little stubby bit if nothing else

 

[HermanTX]

Yes, that's what I thought, there is not that much friction at lower water speeds. I run the pump at 2000 rpm for 12 hours and I get 30gpm at that speed.

The pipes are effectively 1.5 " into 2".

On the other hand, if someone put those smaller sections as a protection, if I happen to run the pump at full speed the protection will still be in place

No flexible pipe , that's a rain spout extension that happened to be laying there before going into the garbage.

Most older pools used 1.5” from the skimmer and main drain so that is the real restriction. Most pools flow just fine with 1.5”
Again, most equipment pads are set up with 2” between pump and filter, then filter to heater because 2” is common connection.

Heaters can handle up to 80gpm so unlikely a concern with majority of pool plumbing.

Now a days it is usually 2” or larger pipe on the suction side and still use 1.5” on the return side with 2” between equipment at the pad.

Your set up is fine.

 

[1poolman1]

I would guess the 'main' pipes are 2", and the old pump was 1.5, so they put a reducer in to marry-up to the pump.

Then when the pump was replaced, rather than cut the pipe at the 2" part and just put a coupler on and then carry 2" to the pump, they cut the 1.5", realized the 2" from the pump wasn't 1.5", and then just threw a reducer on to connect to the existing bit of 1.5" - maybe they had a 2"-1.5" reducer in the truck, and not a 2" coupler...

My OCD would make me replace the little stubby bit if nothing else

Google "Bernoulli's principle" and you will see that the small portion of the plumbing in question has negligible affect on your water flow. If it "bugs' you, replace it. A lot of work if you don't get new Hayward pump unions, or some hi-temp pump unions.

 

[Emiliano]

Google "Bernoulli's principle" and you will see that the small portion of the plumbing in question has negligible affect on your water flow. If it "bugs' you, replace it. A lot of work if you don't get new Hayward pump unions, or some hi-temp pump unions.

Definitely too much work for no benefit. I was just curious why those two smaller sections put in place obviously on purpose. But if it doesn't (or minimally) affect water flow pump efficiency I don't really care.

Thanks all for your answers!