On Sunday, December 1, 2013 12:05:36 PM UTC-6, jullian browne wrote:
I just installed a new thermostat and my furnace is blowing cold air. My pilot light is on but it still not heating up. My furnace is a clare hecla and the model # is G126-LB-C.

The OP neeeds to apply voltage directly to the gas valve using some clip leads or wires. He needs to find out what voltage and where to apply it.

Sounds like he really needs to get professional help, or at least a very handy neighbor with a voltmeter, and paper and pencil to sketch out how the circuit and the auxiliary equipment is connected and then post that info here.