Crescent Enterprises Normally Closed Actuator, 24V, End Switch

One of five met the end of the road, so to speak. Replacement took me about five minutes (even remembered to turn the boiler power off first). Just pay attention to rotating it slightly when installing it over the shaft sticking up from the inline portion. Google, and a son being a technician in the field allowed me to be prepared. This unit has performed flawlessly.

Works well but expensive

Facile à remplacer. Cet item a bien réglé mon problème.

Exact replacement to my old one plus next day shipping for no additional cost

This zone valve head directly replaced a defective one of the same model number on my hydronic boiler heating system. The swap took about a minute. No need to worry about which wires go where, because it's pretty much a "switch" on the black wires and red ones. One thing in the manual that I did not see anywhere else was that you need to lock the unit into the "Open" slot before installing it. I think that just lines up the flat part of the actual brass valve part behind the motor head. When you restore power to the system and this thing sees the call for heat, it will automatically move the lever into the regular position. All in all, great value for a critical component of my system.