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What is the pattern of the blinking? Is it just a constant slow blink or is there a pause like blink blink blink, pause?
OK the slow blinking is usually normal but not receiving a call from thermostat.Can you do some hands on troubleshooting?
We need to determine if issue is with furnace or thermostat first
OK does the inducer vent motor actually come on?
OK the inducer is the small vent motor where vent connects.It has to start and draw a vacuum on pressure switch to close it before anything else can happen.
These furnaces are what is known as a "condensing" furnace which means they actually condense water from the burning process and must be properly drained.
There are hoses in the furnace and a drain going outside.The slightest amount of debris or standing water in the main drain or one of those hoses will effect the vacuum on the switch.Also the slightest blockage in intake or exhaust will effect the vacuum.I have seen as minor as a spider wed in one of the vents cause this. Then add to that ,most of these pressure switches we get are imported from either China or Mexico and not unusual to get a bad one that sticks open or closed.
If inducer is coming on. lets start by doing the following: I want you to locate the pressure switch. It will be a small round canister with a hose attaching it to the inducer housing. Remove hose from inducer housing and leave it attached to the pressure switch. Power off and back on to reset board again, Then call for heat at thermostat. Allow inducer to start then suck on the end of hose still attached to pressure switch and see if switch will close and burners ignite.
Can you attach a photo of furnace with top panel removed?I will point it out
These round silver canisters are the pressure switches. Locate the hose coming from inducer to do the above test.
Can you see where it connects and remove to suck on hose with it still connected to switch?
OK so did furnace come on when you did that?
OK if that did not help, check those hoses that go to drain and make sure no water is standing in them and main drain is not blocked.
Yes the one that came down from top
Is thermostat still calling for heat?
Yes with call for heat continue sucking on hose and see if error code goes away.
I am about to leave office so I will open this to other experts.PLease wait to leave rating until someone is able to finish helping you with this.
Depends on who is online today.Your problem is that the pressure switch is not closing.Could be blocked vent, water standing in one of those hoses or even an issue with heat exchanger, but will be a step by step process of checking each.