The Caleffi 1725G1A is a 172-series thermostatic manifold mixing station with 7 outlets and a Grundfos UPS 15-58 three-speed circulator, holding radiant supply temperature at a fixed set point in the 80 - 130 F range via a thermostatic actuator with built-in sensor, and including a removable primary hydraulic separator with check valve.
Product data compiled from Caleffi North America technical documentation (01155 NA, NA10814, NA11011) and the Caleffi North America product catalogue. Last reviewed August 2026.
Key Features
Fixed-Point Thermostatic Mixing, 80 - 130 F
A three-way brass mixing valve with thermostatic actuator and built-in sensor holds the radiant supply at the set temperature - no electronics or wiring required.
Grundfos UPS 15-58 Three-Speed Pump
Integral Grundfos UPS 15-58 cast-iron circulator, 115 V / 60 Hz, IP44, with three selectable speeds.
Removable Hydraulic Separator
A brass primary-circuit hydraulic separator with POM check valve decouples primary and secondary flows; remove it when connecting to a HYDROLINK or existing separator.
7-Outlet 1-1/4 in Manifold
Serves 7 circuits from a 1-1/4 in manifold with 3/4 in male outlets on 2 in centers; primary connections 3/4 in NPT male.
Supply Temperature Gauge
A top elbow with integral supply temperature gauge gives at-a-glance confirmation of the mixed temperature.
TWISTOP Zone-Actuator Ready
Manifold outlets accept optional TWISTOP thermo-electric actuators for room-by-room zoning.
Outlet Fittings Required - Sold Separately
Circuit outlets are 3/4 in male Eurocone and ship capped. Each loop needs a Caleffi manifold fitting matched to your tubing (680 series for PEX to ASTM F876, 682 series for PEX-AL-PEX to ASTM F1281). Order one fitting per loop.
Technical Data
| Function | Thermostatic manifold mixing station (172 series) |
|---|---|
| Number of outlets | 7 ports, 3/4 in male, 2 in center distance, Eurocone (fittings sold separately) |
| Mixing valve | Three-way brass body, PSU shutter, thermostatic actuator with built-in sensor |
| Control temperature range | 80 - 130 F (25 - 55 C) |
| Circulator | Grundfos UPS 15-58 three-speed, 115 V / 60 Hz, IP44 |
| Hydraulic separator | Brass, removable, with POM check valve |
| Primary connections | 3/4 in NPT male |
| Manifold | 1-1/4 in with supply temperature gauge |
| Maximum operating pressure | 150 psi |
| Adjustment temperature range | 80 - 130 °F |
| Maximum inlet temperature | 195 °F |
| Outlet center distance | 2 in |
Documentation
Technical brochure- Installation & servicing manual
- Revit / BIM content guide
- idronics 7 - Mixing in hydronic systems
Related Products
Frequently Asked Questions
It supplies a 7-circuit radiant floor system at a constant mixed temperature: a thermostatic three-way valve blends boiler water down to a set point between 80 and 130 F, and the integral pump circulates it.
A Grundfos UPS 15-58 cast-iron three-speed circulator, 115 V / 60 Hz.
The removable brass separator with check valve decouples the primary (boiler) and secondary (radiant) circuits when the primary has its own pump; remove it when connecting to a HYDROLINK or an existing separator.
No. The thermostatic actuator has a built-in sensor and holds the set temperature mechanically; individual outlets can still be zoned with optional TWISTOP thermo-electric actuators.
3/4 in NPT male primary connections and a 1-1/4 in manifold with 3/4 in male outlets on 2 in centers.
- Type:
- Thermostatic Mixing Station
- Number of Ports:
- 7
- Pump Type:
- 3-Speed Pump
- Connection Size:
- 1-1/4 in
- Configuration:
- Standard
