---
product_id: 39029102
title: "529912 GU 125 Bronze Union Flange - 3/4\" NPT"
brand: "grundfos"
price: "726 kr"
currency: DKK
in_stock: true
reviews_count: 5
category: "Grundfos"
url: https://www.desertcart.dk/products/39029102-529912-gu-125-bronze-union-flange-3-4-npt
store_origin: DK
region: Denmark
---

# Precision 3/4" NPT connection Seamless fit for Grundfos UP & UPS pumps Complete kit with nuts, gaskets & adapters 529912 GU 125 Bronze Union Flange - 3/4" NPT

**Brand:** grundfos
**Price:** 726 kr
**Availability:** ✅ In Stock

## Summary

> 🔧 Upgrade your pump game with precision and durability!

## Quick Answers

- **What is this?** 529912 GU 125 Bronze Union Flange - 3/4" NPT by grundfos
- **How much does it cost?** 726 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.dk](https://www.desertcart.dk/products/39029102-529912-gu-125-bronze-union-flange-3-4-npt)

## Best For

- grundfos enthusiasts

## Why This Product

- Trusted grundfos brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Durable Bronze Build:** Crafted from premium bronze for long-lasting corrosion resistance and reliability under pressure.
- • **Compact & Lightweight:** At just 8 ounces and 1x1x1 inch, it’s easy to handle and install without bulk or weight concerns.
- • **Trusted Brand Quality:** Manufactured by Grundfos, a global leader in pump technology, guaranteeing superior performance and peace of mind.
- • **All-in-One Convenience:** Includes two nuts, gaskets, and adapters—everything you need for a hassle-free installation.
- • **Effortless Integration:** Designed specifically for Grundfos UP and UPS pumps with 125 Union compatibility, ensuring a perfect fit every time.

## Overview

The Grundfos 529912 GU 125 Bronze Union Flange is a compact, durable plumbing fitting designed for 3/4" NPT connections. It includes all necessary nuts, gaskets, and adapters for seamless installation with Grundfos UP and UPS pumps featuring a 125 Union. Crafted from corrosion-resistant bronze, this flange ensures reliable, long-term performance backed by Grundfos’ trusted engineering.

## Description

The Grundfos GU 125 Bronze Union Flange set includes two nuts, gaskets and adapters. Compatible with Grundfos UP and UPS pumps with 125 Union.

Review: High quality parts that fit perfectly and made the repair job easy - My hot water recirculating system recently had a near catastrophe with severe copper corrosion that necessitated replacement of the pipes leading to and from the Grundfos recirculating pump. Since the system had originally been assembled with soldered joints, I had to replace the union flanges on both sides of the pump. As you would expect from Grundfos, these components are very well made and heavy duty. I opted to go with NPT joints this time to make it easier if I ever need to replace the surrounding copper pipes again. The project went well, and these flanges fit the original pump perfectly. I’m very happy with the quality of these parts.
Review: Great quality - Perfect fit and great quality

## Features

- Grundfos GU 125 Bronze Union Flange
- Includes two nuts, gaskets and adapters
- Compatible with Grundfos UP and UPS pumps with 125 Union
- 3/4" NPT connection

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | Grundfos |
| Brand | Grundfos |
| Model | 529912 |
| Item Weight | 8 ounces |
| Product Dimensions | 1 x 1 x 1 inches |
| Item model number | 529912 |
| Manufacturer Part Number | 529912 |

## Images

![529912 GU 125 Bronze Union Flange - 3/4" NPT - Image 1](https://m.media-amazon.com/images/I/51-ECqfotjL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ High quality parts that fit perfectly and made the repair job easy
*by A***K on April 8, 2025*

My hot water recirculating system recently had a near catastrophe with severe copper corrosion that necessitated replacement of the pipes leading to and from the Grundfos recirculating pump. Since the system had originally been assembled with soldered joints, I had to replace the union flanges on both sides of the pump. As you would expect from Grundfos, these components are very well made and heavy duty. I opted to go with NPT joints this time to make it easier if I ever need to replace the surrounding copper pipes again. The project went well, and these flanges fit the original pump perfectly. I’m very happy with the quality of these parts.

### ⭐⭐⭐⭐⭐ Great quality
*by R***A on December 16, 2024*

Perfect fit and great quality

### ⭐⭐⭐⭐⭐ Makes installation and removal easier.
*by D***N on February 22, 2024*

I replaced my old recirculation pump with a newer model. The new model uses these union joints so that if I ever need to remove and replace the pump it will be much easier. Seemed a bit pricy though.

## Frequently Bought Together

- Grundfos 529912 GU 125 Bronze Union Flange - 3/4" NPT
- GRUNDFOS UP15-29SU/LC 59896776
- Grundfos 59896775 1/12 hp 115V Circulating Pump

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**Shop now:** [https://www.desertcart.dk/products/39029102-529912-gu-125-bronze-union-flange-3-4-npt](https://www.desertcart.dk/products/39029102-529912-gu-125-bronze-union-flange-3-4-npt)

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*Product available on Desertcart Denmark*
*Store origin: DK*
*Last updated: 2026-02-03*