My compliments to Rdownward for his persistence in tracking down the wiring and the associated dip-switch settings. Normally, the problem with the furnance is the need to set the thermostat on zone 1--this is how the dip-switches were set at the factory. Apparently, someone tried to change the dips so the furnance was "slaved" to zone 2. Not sure I would have thought about changing the wiring so the dip switches were compatibility. Well done!!!!!
2003 40' MDTS
Garden Ridge, Texas