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Goodman code problem three blinks

I have two newly installed (one month ago) 92% direct vent heating systems. I have turned on the thermostat for the first time after the hot summer and neither unit worked. My installer returned and bled the gas line and sucked on some hoses and determined that one unit has a blocked exhaust. he's returned during daylight and charging me to fix the blockage which is ok if it really a blockage --act of nature or God like leaves or a pest in the pipe---but now the other unit is also blinking 3 blinks and will not pump heat. what else could be wrong --ie an installation problem?

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Re: goodman code problem three blinks

Same problem with 1 yr old Goodman. Checked entire exhaust and pressure switch. Inside fan, pressure switch hose clogged with crusty white gunk. Cleaned it & furnace fixed. I have no furnace repair experience, but love to "play MacGyver". Hopefully this could save someone a service call.

Posted on Nov 12, 2009

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Re: goodman code problem three blinks

I just had the problem with my new Goodman Furnace. The diagnostic code was flashing three fast blinks. I thought I had a problem with my exhaust being clogged as just a few days prior in a windstorm I had my chimney cap blow off and I thought I had a pest or something blocking the exhaust. I got to looking around and the combustion/exhaust fan had an orange wire behind it. The fan can easily be turned by hand and I had noticed a rough sound when it spun. I soon found out that this orange wire that had been behind the outside of the fan had been cut and this wire apparently supplied some sort of signal or power to a pressure switch. (judging that the three blinks meant a pressure switch stuck open from the inside of the bottow panel) I spliced the wire back in with itself (with the power the ther furnace off) and the furnace immediatly fired up and worked fine. This is probably just an installation error that the furnace installer made, but I was able to fix the problem myself and I have no prior furnace maintenance experience. Just a possible thing to check.

Posted on Mar 07, 2008

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Re: goodman code problem three blinks

If you remove the access panel on the unit and flip the back toward you, you will notice the diagnostic error codes. 3 Blinks represent a problem with the combustion fan, pressure switch or a vent blockage. Here are some things you can do to test it. With a piece of electrical tape holding the door switch, the unit will attempt to start up if the thermostat is calling for heat. The ignition sequence will be that there will be a light blinking on the control board and the combustion/exhaust fan will start turning. Then if there are no restrictions in the venting or combustion chamber, a pressure switch will close allowing the ignition to turn on and get hot. You may notice a viewing port where an orange glow will be seen. After about 15 seconds, you should hear a click and notice the orange turned to blue. If the unit does not light up, you will need to make sure the combustion/exhaust fan is blowing out enough air. Go outside and see if there is a good flow of air coming out of the exhaust vent pipe (if you can get to it). If you are able to temporarily remove the fresh air inlet (supply air) to the furnace to test for a blockage in it, do so but always remember to reinstall it prior to using the furnace. Cycle the furnace again and see if it lights with the supply air vent off (not the exhaust vent). Restriction in intake vent? Now if you did not discover blockage, you may be looking at a weak pressure switch, bad igniter or even misadjusted gas pressure. All these should be covered under warranty from your installer if the furnace is new. Let me know what you found!

Posted on Sep 18, 2007

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Re: goodman code problem three blinks

Where is the pressure switch and how can I clear the hoses to it??? I think this is my problem.

Posted on Nov 25, 2012

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Goodman HVAC Package Unit

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Get back to us with those codes and maybe we can help you further.

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