Hi,

I have a Armstrong Air Ultra V - Tech 80 furnace with a Honeywell
Smartvalve II SV9520H which doesn't start. Here are the details about
the problem:

1. When the thermostat is on the OFF position, the led indicating the
status is showing the normal function "heartbeat"
2. Turn the heat on the thermostat (80 F) and set the thermostat to
AUTO - nothing happens, the furnace won't kick off.
3. Set the thermostat switch to ON - the blower kicks off but the gas
won't light. After about 20-30 seconds, the status led starts flashing
3 times which means: "Presure switch open. Should be closed".

NOTE: The gas is on and the furnace turned on from the main switch.

Any idea of what might be wrong with the furnace and how can I solve
the problem?

Thanks,
Adrian