Can I install a 1 inch water softener on 1.5 pipe?

[JeremyF559]

We have a well and our waterline going into the house is 1.5 inches. Our interior water lines aren’t 1.5 inch so that’s why I’m thinking I can use an adapter to 1 inch. We don’t want to drastically lose water pressure though. Please let me know your thoughts and if it’s advisable.

 

[Bannerman]

We have a well and our waterline going into the house is 1.5 inches. Our interior water lines aren’t 1.5 inch

It's common for the incoming line from a submersible well pump to the pressure tank to be larger than the home's internal piping.

You mention your interior lines aren't 1.5" but didn't specify the main line size. To comply with plumbing code, the connection to the softener is not to be reduced so if the main distribution line through your home is 1", then a 1" softner connection should be appropriate. That said, what softener valve are you installing?

 

[Sponsor]

 

[Reach4]

We have a well and our waterline going into the house is 1.5 inches. Our interior water lines aren’t 1.5 inch so that’s why I’m thinking I can use an adapter to 1 inch. We don’t want to drastically lose water pressure though. Please let me know your thoughts and if it’s advisable.

I would do it. I am not a pro.

You mention your interior lines aren't 1.5" but didn't specify the main line size. To comply with plumbing code, the connection to the softener is not to be reduced so if the main distribution line through your home is 1", then a 1" softner connection should be appropriate.

Here is a snip from 2015 version of UPC I found on http://epubs.iapmo.org/UPC/mobile/index.html#p=143

The way I see it, the main thing is to analyze the flow needs, and in the absence of pressure drop information, the diameter thing comes into play. If the flow from the softener an at an acceptable pressure drop to supply the downstream fixtures, things are good.

Even if there was a literal code violation, and I think it is probably not in my non-professional opinion, they are not going to gig Jeremy.

 

[ditttohead]

Just install a properly sized unit. Check out the 5812 with the 1.5" riser. This is the highest flowing residential system and while it is technically a 1.25" valve, it has 1.5" connections. It technically meets code. https://view.publitas.com/impact-water-products/2018-catalog-final/page/48-49

Here is an article about flow rates and codes. And... no, you can not reduce the pipe size. The code leaves some wiggle room regarding internal system designs, more of a classroom session than a DIY topic though.


Here is the 5812 pages, they are available with the 1.5" riser on 4" tank necks.
https://view.publitas.com/impact-water-products/2018-catalog-final/page/50-51

https://view.publitas.com/impact-water-products/2018-catalog-final/page/36-37