Furnace not working

JackMS wrote:
According to the link you sent, the dip switch for the furnace was wrong. When I switched it to match the others, that was the correct way- if pushed in at the bottom is off. But it still didn’t work. Do I need to reset the thermostat for that change to take effect?. If not, I will start working on cleaning connectors.

Lets make the DIP switch question simple. 99% of the time MOST of the DIP switches will be the same indent---OFF. On a 5 Button front AC/HP, you will have the Furnace ON, and will be the ONLY DIP switch you will have ON, for the Zone 1 board. So, it makes it easy, only one DIP switch will be opposite of the others---The furnace. Now, IF the furnace shows on the 5 button and the DIP was indeed OFF and you then turned it ON, you need to do the reset. ALL a reset does is verify the DIP settings for the Zone 1/2/3/4 AC boards. NOTHING ELSE. There is no magical reset like on a Computer or other appliance that will fix operational problems. IF the 5 button shows furnace AFTER the reset, then the 4 wire modular Communication cable or ends would not be a factor, like corrosion. But, yes, after the reset and you turn the furnace ON at the 5 button, BOTH blue wires should have 12 volt. IF NOT, I would suspect the relay on the board is bad. But that is extremely rare. The blue wires---12 volts comes FROM the furnace to the Board and is connected to one of the blue wires. It makes no difference which blue wire. The board closes the relay in furnace mode and 12 volts comes out back down to the furnace. Very simple system. Doug