The Caleffi Z307537 is a Z-one 3-way zone valve body with 3/4" Sweat connections, 7.5 Cv and 20 psi maximum close-off differential pressure. Supplied as a valve body only; a Z1 series actuator is ordered separately.
Best for domestic hot water and potable applications service where the body must seat bubble-tight against up to 20 psi differential.
Warranty
Key Features
100 %% Bubble-Tight Close-Off
The peroxide-cured EPDM paddle and seals give 100 percent bubble-tight seat close-off leakage at up to 20 psi differential.
7.5 Cv Flow Capacity
Sized at 7.5 Cv, one of five flow capacities in the Z-one range, so the body can be matched to the circuit rather than the pipe size.
Rated to 300 psi and 240 deg F
Forged brass body rated to 300 psi static and 32 to 240 deg F, plus 15 psi low pressure steam.
Push Button Actuator Mount
A Z1 series actuator locks on with a push button and no fasteners, and lifts off for service without breaking the pipe joint.
Low-Lead Brass
Low-lead brass body under 0.25 percent lead content, compliant with NSF/ANSI/CAN 372 as certified by ICC-ES, file PMG-1360, for domestic hot water use.
Diverting or Mixing
Installed on the flow side the body diverts; installed on the return side it mixes. A three-way body cannot be converted to two-way.
Technical Specifications
| Product Type | Motorized Zone Valve Body |
| Series | Z-one |
| Configuration | 3-Way diverting or mixing |
| Connection type | Sweat |
| Connection size | 3/4" |
| Flow coefficient | 7.5 Cv |
| Max. close-off differential pressure | 20 psi |
| Max. static pressure | 300 psi (15 psi steam) |
| Medium temperature range | 32 - 240 deg F |
| Medium | Water, glycol solutions, low pressure steam |
| Max. percentage of glycol | 50 % |
| Close-off seat leakage | 100 % bubble-tight |
| Body material | Low-lead brass (under 0.25 % lead) |
| Stem / seals | Stainless steel stem; peroxide-cured EPDM o-rings and paddle |
| Supplied as | Valve body only - actuator ordered separately |
| Lead-free certification | NSF/ANSI/CAN 372, ICC-ES file PMG-1360 |
Specifications transcribed from Caleffi technical brochure 01115/23.1 NA and installation manual NA10073. Last verified August 2026.
Documentation
Related Products
- Caleffi Z300431 : Z-one 3-Way Zone Valve Body, 1/2" Sweat, 1.0 Cv, 75 psi Close-Off (Valve Only)
- Caleffi Z300432 : Z-one 3-Way Zone Valve Body, 1/2" Sweat, 2.5 Cv, 50 psi Close-Off (Valve Only)
- Caleffi Z307433 : Z-one 3-Way Zone Valve Body, 1/2" Sweat Low-Lead Brass, 3.5 Cv, 30 psi Close-Off (Valve Only)
- Caleffi Z300532 : Z-one 3-Way Zone Valve Body, 3/4" Sweat, 2.5 Cv, 50 psi Close-Off (Valve Only)
Frequently Asked Questions
What is the Caleffi Z307537?
It is a Z-one 3-way motorized zone valve body with 3/4" Sweat connections and a 7.5 Cv flow coefficient. It is the valve body only and takes a Caleffi Z1 series actuator.
What differential pressure will the Caleffi Z307537 close against?
Up to 20 psi. Close-off differential falls as flow capacity rises across the Z-one range, from 75 psi at 1.0 Cv to 20 psi at 7.5 Cv.
Does the Caleffi Z307537 include an actuator?
No. It is supplied as a valve body only. Pair it with a Z1 series actuator such as the Z111000 or Z151000, or order a pre-matched Z-series quick order code.
Is the Caleffi Z307537 lead-free?
Yes. The body is low-lead brass under 0.25 percent lead content and complies with NSF/ANSI/CAN 372 as certified by ICC-ES under file PMG-1360, so it is suitable for domestic hot water.
- Product Type:
- Motorized Zone Valve Body
- Product Family:
- Z-one Zone Valves
- Series:
- Z3 3-Way Valve Body
- Configuration:
- 3-Way
- Connection Type:
- Sweat
- Connection Size:
- 3/4 inch
- Flow Coefficient:
- 7.5 Cv
- Max Close-Off Pressure:
- 20 psi
- Body Material:
- Low-Lead Brass
- Max Operating Pressure:
- 300 psi
- Medium Temperature Range:
- 32 - 240 deg F
