I have a very old thermosat that has six wires hooked up to it now. it is labled
2-white wire
0-brown wire
B-blue wire
R-red wire
Y-yellow wire
G-green wire
the honey well thermostat I bought has 5 connections Rh, Rc, W, Y, G with it only having 5 and my current has 6 is this thermostat going to work or not? I appreciate any info. thank you so much

The "O" circuit suggests that you have a heat pump, or some device that is powered when cooling is selected. If the brown wire is actually used/connected to something, the thermostat you have won't work.

The 6th may not be hooked up or needed.
Would be good to check in air handler what each wire is connected to and controls.
Often, Red is common power, white is heat,
blue may be cool, and green for the fan.
The extra wire may be from the other side of the transformer.

The 6th may not be hooked up or needed.
Would be good to check in air handler what each wire is connected to and controls.
Often, Red is common power, white is heat,
blue may be cool, and green for the fan.
The extra wire may be from the other side of the transformer.

what would be the best way to check if wires are working?

what would be the best way to check if wires are working?Trace them to find out what, if anything, they are connected to. P.S. The "Y" (yellow) is typically used for control of cooling and/or heat pump circuit.

Strat: Terminology problem

Often, Red is common power

Red is usually 24 Vac.

Common is the lead they left out when the stats were mercury switch based. Common is necessary if the stat needs continuous power.

I was referring red as to being common with respect to each circuit, as a rotary switch has a common and out to numerous poles. heat, compressor, contactor, blower.
Forgive my termonology.
I would look in Air Handler.