Caleffi Zone Valves - Advantages

Caleffi Zone Valves - Advantages

Rathe Knowledge Base
Caleffi Zone Valves



Not All-Zone Valves Are The Same!




Watch The Video



Valve Construction 

Aluminum Frame - Does Not Rust. The case is a Plastic Poly Carbon - Which also creates a thermal break. Helps keep heat away from the motor & gear train. Temps can see 190F. The plastic Poly Cover also provides protection from sweating or water dripping on the valve.

  1. Valve Paddle: Made from EPDM rubber material. Very durable to chlorine and other chemicals. Longer Life. Can be used on Heating & Low-Pressure Steam Applications.
  2. Valve Body-Oversized. When water flows through an oversized body, it slows down, less velocity. It's easier for the valve to open & close.
  3. The arrow on the body shows flow direction.




Springs & Gears:

Caleffi uses a coil spring which always maintains the same tension. That means it’s a balanced closing process. Competitors use garage door type of springs. With these dual springs typically they will not have the same tension from the 2 springs which can cause issues in properly sealing the valve when it closes.

 




Notes
Note that the Caleffi Gears are 2 Times the thickness as the competitors




Loss Motion Technology:
All normally closed zone valve motors allow the zone to operate as long as there is power to the motor. When the call for heat is satisfied, power is turned off to the zone valve motor and the valve closes by the springs inside the valve. The motor is basically in a free fall back to the close position until the valve seat hits the valve body and comes to a crashing halt. This constant crashing will ultimately cause  the gears & motor to fail.
InfoAdvantage of using loss motion gear technology: When the call for heat is over and power is released from the motor, the coil spring will drive the valve seat closed. When the valve seat is approaching the closed position, the pinon gear (which is the smaller gear - see videos) is released from the motor gear and the motor glides to a stop.



Helpful Explainer Videos


     




Info

The Blue gear (pinion gear) would be the gear connected to the motor.

The green gear is released from the pinion gear when the valve seat starts to approach the valve close position. This release of the two gears prevents stress on the motor which leads to failure. 



End Switch:

End switches have always been problematic. The contacts are exposed to the conditions around or in the valve and have premature failures from corrosion. (See Picture A)

Caleffi uses a hermetically sealed reed switch - which the auto industry has used for years. They are tested to 1 Million cycles and are not exposed to the elements. Works with a magnet that enables the end switch.  (See Picture B)




 
Picture A - Typical End Switch - Contacts are open to the environment.
                    Arm pushing against a microswitch to close end switch.



 

     Picture B- Caleffi Reed Switch Totally Enclosed and now protected from the environment.
                                  





As gears rotate the magnet brushes up next to the 
Reed Switch which then activates the end switch. 
                                                           

Features:

  1. Used in hydronic, chilled water & steam applications
  2. 1/2" up to 1-1/4"
  3. Pop off Head
  4. Manual bypass lever.
  5. Most connections -Sweat-Crimp-NPT-Pex
  6. Voltages available: 24v - 110v - ;208v - 230v NO or NC 
  7. Terminal Block
  8. 18" leads
  9. 5 - Valves wired to a 40va transformer. Motor=7 Va
  10. Z45 has 7.5 Cv (Big Opening)!
  11. Slomin's uses Caleffi Zone Valves

 



Notes:

  1. Water hammering is usually from an oversized pump. Either install a PDV or Compass type pump.
  2. Supply or return the zone valve can be installed. On the supply you eliminate ghost flows.
  3. If the pump is on the supply and zone valves are on the return, it may help eliminate water hammering, but using PDV or Compass pumps is a better solution.


Pinion Gear Definition: