Caleffi Z55 : 2-Way Valve, 3/4" Sweat, 7.5 Cv, 20 psi ΔP, Normally Closed Spring Return Valve Actuator, 24V AC, On/Off Control Signal, (1) SPST 0.4A Auxiliary Switch, Terminal Block
The Caleffi Z55 is a 2-way motorized zone valve assembly featuring a 3/4" sweat valve body and a Z151000 normally closed spring-return actuator with screw terminal connections. It provides reliable on/off control for hydronic heating and cooling applications. The actuator closes the valve automatically when power is removed, ensuring safe system operation.
UL873, cULus Listed, and CE certified, the Z55 meets UL 1995 section 18 requirements for air plenums and ducts. The integrated SPST auxiliary microswitch allows for system feedback or control interlock. The valve’s brass construction, stainless steel stem, and EPDM seals ensure long-lasting durability and corrosion resistance in hydronic systems.
Key Features
- 2-way motorized zone valve with normally closed actuator
- 3/4" sweat connections for copper piping
- Spring-return actuator automatically closes on power loss
- Screw terminal block for simple, reliable wiring
- Integrated SPST auxiliary microswitch (0.4A @ 24V AC)
- UL, cULus, and CE certified for air plenum and duct installations
Technical Specifications
- Valve Type: 2-Way Straight
- Connection Type: 3/4" Sweat
- Maximum Operating Pressure: 300 psi
- Maximum ΔP: 20 psi
- Cv Rating: 7.5 gpm
- Medium Temperature Range: 32–240 °F
- Electric Supply: 24V AC
- Power Consumption: 7 VA (at full capacity)
- Auxiliary Switch Rating: 0.4A @ 24V AC
- Maximum Glycol Concentration: 50%
- Medium: Water, glycol solutions, vapor (max 15 psi)
Datasheets
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Caleffi Z-One Motorized Zone Valve Installation and Commissioning Manual |
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- Valve Pattern:
- 2-Way
- Valve Size:
- 3/4 Inch
- Connection Type:
- Sweat
- CV Rating:
- 7.5
- GPM:
- 15 @ 4 psi
- Actuator Type:
- Non Fail-Safe
- Voltage:
- 24VAC
- Control Signal:
- On/Off
- Auxillary Switch:
- Yes
- NEMA 4X Enclosure:
- No
