The Story
Grundfos 529912 — 3/4″ Bronze Union Threaded End Pair
The Grundfos 529912 fits GU-125 union pumps (UP/UPS family), providing a reliable connection point with 3/4″ NPT threaded ends. This pair includes nuts, gaskets, and adapters to make installation or replacement straightforward.
Key Features & Benefits
- Pair of bronze half unions compatible with GU-125 union pumps
- Includes nuts, gaskets, and adapters for direct installation
- 3/4″ NPT threaded connection ensures broad compatibility
- Ideal for use when replacing or upgrading circulator piping
- Durable bronze construction resists corrosion and wear
Applications
- Replacement or repair of UP / UPS series circulator pump unions
- Hydronic heating and domestic hot-water systems using GU-125 unions
- Any piping system needing detachable union ends for serviceability
Specifications
| Part Number / SKU | 529912 |
| Type | Half-Union Threaded End (Pair) |
| Connection Size | 3/4″ NPT |
| Compatible Union Size | GU-125 series |
| Material | Bronze |
| Included Items | 2 nuts, 2 gaskets, adapters |
Common Questions
Q: Will this fit my UP15-29 SU circulator pump?
A: Yes — it’s compatible with GU-125 unions used on many UP / UPS models.
Q: Does it come with gaskets?
A: Yes — the set includes gaskets, nuts, and adapters.
Q: Can it be used on a different size union?
A: Only if your pump uses the same GU-125 standard and you confirm dimensions match.
A dependable bronze union pair for service, repair, or replacement — keep your circulator connections solid and serviceable.
Details & Craftsmanship
Every detail has been carefully considered to bring you the perfect product.
Description
Grundfos 529912 — 3/4″ Bronze Union Threaded End Pair
The Grundfos 529912 fits GU-125 union pumps (UP/UPS family), providing a reliable connection point with 3/4″ NPT threaded ends. This pair includes nuts, gaskets, and adapters to make installation or replacement straightforward.
Key Features & Benefits
- Pair of bronze half unions compatible with GU-125 union pumps
- Includes nuts, gaskets, and adapters for direct installation
- 3/4″ NPT threaded connection ensures broad compatibility
- Ideal for use when replacing or upgrading circulator piping
- Durable bronze construction resists corrosion and wear
Applications
- Replacement or repair of UP / UPS series circulator pump unions
- Hydronic heating and domestic hot-water systems using GU-125 unions
- Any piping system needing detachable union ends for serviceability
Specifications
| Part Number / SKU | 529912 |
| Type | Half-Union Threaded End (Pair) |
| Connection Size | 3/4″ NPT |
| Compatible Union Size | GU-125 series |
| Material | Bronze |
| Included Items | 2 nuts, 2 gaskets, adapters |
Common Questions
Q: Will this fit my UP15-29 SU circulator pump?
A: Yes — it’s compatible with GU-125 unions used on many UP / UPS models.
Q: Does it come with gaskets?
A: Yes — the set includes gaskets, nuts, and adapters.
Q: Can it be used on a different size union?
A: Only if your pump uses the same GU-125 standard and you confirm dimensions match.
A dependable bronze union pair for service, repair, or replacement — keep your circulator connections solid and serviceable.
