The Caleffi 1725I1A is a 172-series thermostatic manifold mixing station with 9 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 (01170 NA, 01155 NA). Last reviewed July 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.
9-Outlet 1-1/4 in Manifold
Serves 9 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.
Technical Data
| Function | Thermostatic manifold mixing station (172 series) |
|---|---|
| Number of outlets | 9 ports, 3/4 in male, 2 in center distance |
| 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 brochureRelated Products
Frequently Asked Questions
It supplies a 9-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:
- 9
- Pump Type:
- 3-Speed Pump
- Connection Size:
- 1-1/4 in
- Configuration:
- Standard