end switch

Post the drawing.

It sounds like it may be the switch, that if not installed properly, will cause a couple of city blocks to be leveled.

.

No thats only if the red wire is cut. Connecting the wire will cause implosion, black holes or something.

Working with a boiler start circuit, the end switch could be from a combustion air damper or water flow switch that must be proved before the boiler start circuit is completed. A complete system layout showing all devices in your system would help.

ilcllc@comcast.net

www.innovativelogicalcontrols.com

From the Taco wiring diagram that you apparently have - very first statement after diagrams:

Operation:

When any thermostat calls for heat, the appropriate circulator

is energized and the isolated end switch (X and X) will start the

boiler.

Thanks for your response, I understand it now, and in my case I did not have to use the end switch.

chibcha38; the thermostat & 24 ac volt transformer are wired to operate the zone valve, when valve is opened to allow water to flow the end switch closes to turn on the boiler & circulating pump. the end switch connected to the T T terminals on the boiler or the zone control panel. perry

Thanks for your response, I understand it now, and in my case I did not have to use the end switch.