I have an old therostat that has a W2 and Y wires. Well the new thermostat instructions say talk to an HVAC

Question

My current thermostat has B,G,R X,E,Y,W2,L, and O but no wires on L and O. the new thermostat has E, AUX,Y,G,O,L,R,B, AND C. Any thoughts, the instructions said contact and HVAC guy if i had a W2 and a Y wire.

also my W2 is tied to E

Answer 1

you have to know what brand you are hooking.  some thermostats will not work with certain units.  And another is if you are hooking up to a heat pump unit, there are more wires to hook up to.

Answer 2

L is usually a fault indicator light and is not used on all systems.

O is for the reversing valve energized in cooling yours must be using B for reversing valve energized in heating.

W2 is typically connected with E, both are for different stages of electric strip heating.

Sounds like everything should work as you have it.