I changed our 2 wire taco thermostat to a new programmable Honeywell. The taco only has 2 wires; a white and a black. The white was hooked to the Y connector and the black was hooked to the R connector. I hooked the black to the R connector on the new system and the white to the W connector. Is this right? The temperature keeps rising and it's getting way to hot in here. Help!

Try Rh and W

How thick were these wires? It's rare to have a black and white unless it is line voltage. I suspect you may have used the wrong thermostat.

What kind of furnace do you have and is there AC

If there is only two wires it's either heat or cool... not both.