The cold start circuit is possibly not working. It is composed of a cold start valve and a thermal/time switch that is in the thermostat housing. Guessing from cyberspace would be starting with the switch, they are usually the easiest to eliminate from the equation. If bypassing the switch allows power to reach the cold start valve, the repair is quite straight forward.
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Monday, March 1st, 2010 AT 10:31 AM