The Caleffi R31589 is a union nut with a 1-1/2 in connection for Caleffi PresCal products, providing the union joint that lets the host valve or separator be installed and removed without cutting pipe.
Product data compiled from Caleffi North America technical documentation. Last reviewed July 2026.
FunctionUnion Nut
For LinePresCal
Connection1-1/2 in
Warranty2 Years
Key Features
Genuine Union Nut
Correct thread form and depth for the matching Caleffi union tailpiece and body.
Genuine Caleffi Part
Factory fitting with correct dimensions and sealing geometry.
Technical Data
| Function | Union Nut |
|---|---|
| For product line | PresCal |
| Description | 1-1/2 in Union Nut |
| Connection size | 1-1/2 in |
Related Products
Caleffi NA107151-1/2 in Union NutCaleffi R530041-1/2 in Union NutCaleffi R00014521-1/4 in Union NutCaleffi F610081 in Union Nut
Frequently Asked Questions
What does the Caleffi R31589 fit?
It is the genuine fitting for Caleffi PresCal products. Match your host model number and connection size before ordering.
2-Year Limited Warranty. Backed by Caleffi North America's limited warranty against defects in material and workmanship for two years from date of shipment. See Caleffi's limited warranty for full terms.
- Type:
- Union Nut
- For Product Line:
- PresCal
- Connection Size:
- 1-1/2 in