Three Wire Thermostat Diagram. Hi im trying to replace an old honeywell thermostat with a more modern one. Injunction of two wires is usually indicated by black dot to the intersection of two lines.
The new thermostat has two pins marked w and com mon. White black r 110 v power source 24 v thermostat p n 8200008 rc y b o rh g w zone valve unit bypass main back to outdoor furnace c w r c note thermostats must be installed by quali ed technician. This wire allows power to enter the unit.
We include wiring diagrams and installation instructions for most zone valve model and priority operation.
If the boiler manufacturer recommends a wiring diagram follow. Wiring a thermostat is a simple step by step process that anyone can do. Most of the process is about following safety procedures and avoiding common mistakes. Was 1767 save 168 9.