Draft Inducer Blower Not Blowing- LED Blinking 3 Times

rust101 · 11-28-2009, 01:29 PM

I have an Amana Gas Fired Furnace Model CCA24FCC. It was part of a new house purchase in 2004. It is located in my garage and shares the venting system with the water heater which is located a few feet away. I hadn't had a need for heating the house until recently as we just a had a cold snap come through Georgia.
The furnace recently started blowing cold air out of the vent registers in the house after a call for heat and would then shut off after a few minutes with the thermostat with setting on "Auto". In the thermostat "ON" setting the circulator fan just blows ambient temperature air.
Upon further investigation I have a blinking LED coming from the circuit board. It blinks three times. The manual says- pressure switch circuit not closed. Exactly! The induced draft blower is not spinning. When a call for heat occurs this fan does not even attempt to spin.
I have verified the pressure switch is functioning- with the furnace off or no movement of the induced draft blower, the switch has no continuity across its terminals. When I pull a slight vacuum on the switch, I can hear it click and then my ohmeter has continuity across it. The problem is the draft motor wont run to pull the vacuum to create the sequence of events to fire the burners.
When the furnace is switched on or a call for heat occurs, there is no voltage at the induced draft blower motor terminals nor do I have voltage at the control unit terminals which lead to the blower.
Am I on the right track to replacing the control unit?
To recap:
It appears the pressure switch works as designed.
The induced draft blower fan does not have adequate power supply.
Lack of power supply was traced back to the terminals at the circuit board.
I had hoped that there was a relay, breaker or fuse I could replace instead of the entire board, but I am unsure of the next best step.
I live in a townhome and I have the exact same model in my attic which supplies heat to the upstairs. Any suggestions on potential parts swapping to verify failure?
By the way, I had skipped replacing my filters for a few months and they were really dirty when I replaced them today while diagnosing the furnace. I noticed when removing the furnace filter that it looked as though it had a water stain on it. (possibly from condensation of some sort) The circuit board is right above where the stain was located.

yuri · 11-28-2009, 01:38 PM

Post some pics of the furnace with both doors off and the control board and water stain. If water hit the board and damaged it then the relay for the fan may be faulty etc.

rust101 · 11-28-2009, 02:20 PM

Yuri, I have the pictures, but something is prohibiting me from uploading them into this thread.

rust101 · 11-28-2009, 02:34 PM

http://www.flickr.com/photos/45063368@N02/?saved=1

This is the only way I could figure to get the photos visible to those kind souls that have taken the time to review this thread. thanks again for the support!

yuri · 11-28-2009, 03:01 PM

Doesn't look like water damage. Try GENTLY tapping on those black relays when it is calling for heat, power from W to C. One of them is for the ventor fan. If it starts then the board is faulty, tapping is not a solution. Not sure how old that unit is but those relays do fail a lot.

rust101 · 11-29-2009, 09:19 AM

I tapped on the relays and could not get anything to happen. I did jumper power to the draft blower and got it to work. It was creating enough vacuum to move the switch in the pressure sensor. I could hear it switching as I slipped the hose on and off the nipple. The burners never fired though. I can only assume that there must be something wrong with the board. Mechanically, the blower and the pressure sensor appear to be operational. The board is just not sending power to the blower to begin with. The furnace is about 5 years old.

rust101 · 11-29-2009, 09:54 AM

Looks like the circuit board P/N 102077-18 supersedes to RF000129. Anybody have any final suggestions before I press the button on this $150 part?

rust101 · 12-03-2009, 07:31 AM

As a follow up, I received the control board in the mail yesterday. I installed it in less than 1/2 hour and the furnace is now pumping warm air throughout my house. Thanks for the confirmation Yuri!

Marty S. · 12-03-2009, 07:29 PM

Rust, did you call anyone to see if the part was still under warranty? Most new furnaces come with 5 year parts warranties.

rust101 · 12-04-2009, 07:59 AM

Marty, I just passed my 5 year mark about 3 months ago. The part only cost me $95.

rust101 · 04-09-2013, 09:44 PM

So we are in the shoulder season here in Georgia where we jump from a little A/C in the daytime and occasionally have the need for heat at night. The other day we noticed that the air coming out of the vents with A/C on smelled a little musty. It was not not quite like dirty socks but not quite like fresh conditioned air either.
I suspected the coil to be moldy or mildewed so I inspected it and it looked fine. I sprayed some coil cleaner on it just for the heck of it. Later that night we turned the heat on and the burners never lit. So we had stinky air with A/C on and no heat.
When calling for heat, the circulator blower continued to run and the induced draft blower never ran. After it cycled, the LED was blinking 4 times. The code is for an open primary or auxiliary circuit. The upstairs furnace is working great so I tried swapping the switches into the non-heat unit. No resolution. I then swapped the integrated circuit board. No resolution.
I have recently replaced very dirty filters. I do notice lower circulator blower output through the vents. When the A/C is on the air coming out of the vents smells and the speed and volume seems less than the working units vents. I can't see or feel of any blockages in the air inlets. I am thinking about swapping the circulator blower to see if that is the issue. Any thoughts?