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Pipe size reduction at water softener

A previous owner installed a water softener by slicing the 1" water supply from the street and feeding the flow from the street through the water softener then back out to the house. The issue is they reduced the copper piping to 3/4" for the 3ft from the splice to the water softener, then increased to a 1" fitting to attach to the input of the water softener. Then, the 1" fitting on the output of the water softener was again reduced to 3/4" for the 3ft back to the house-side of the spliced water line, which increased back to the original 1" pipe. Given this scenario, am I losing water pressure to any real measurable degree?

The new water softener I am installing also has 1" fittings for input / output and I have the opportunity to remove the 3/4" piping and replace with 1". I just want to ensure that by doing so, I will have a more efficient system.

Just some details: 4 bath, two story house in San Antonio, TX. Water softener is tapped where water from street immediately enters the house. not sure how much further in the walls where the 1" drops to 3/4" or 1/2" before reaching the fixtures (most sink and shower fixtures are 1/2" at the shutoffs and mixers).



Re: Pipe size reduction at water softener

Think of the reduction as a partially closed faucet.


Re: Pipe size reduction at water softener

You probably won't notice a drop in pressure until you open multiple faucets simultaneously.

The 90-degree fittings offer more resistance (due to turbulence in the water) than the short length of 3/4" pipe.

I recommend replacing the 3/4" with 1" anyway -- not because the larger pipe will give you better flow, but because the larger fittings will.

Re: Pipe size reduction at water softener

What is your water pressure? if it is 75 psi or more don't sweat it . If however your pressure is below 50 psi the i would remove as much 3/4 pipe and fittings
as fencepost mentioned.


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