# Carrier 9200 Code 34 fault



## yuri (Nov 29, 2008)

It may be that your igniter is getting weak/not glowing red/hot enough/fast enough. Color/temp of it is important. The gas valve may not be opening properly. Check your intake/exhaust pipes for obstructions. Poor airflow thru the burner box can cause ignition problems. Remove the front of the burner box and carefully look inside where the plastic pipe attaches for a plastic screen. Had one plug up with debris once.


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## cu1982 (Dec 26, 2008)

*Obstruction*

Thanks Yuri,
I did check both intake and exhaust. When the inducer blower was working there was good airflow both in and out.... Don't know how to relate just how "red" the ignitor is getting since I don't have something to judge it against. Quick question for you... a number of related posts have mentioned the sensor possibly being bad. If it was truly and completely bad, wouldn't I see the blue flame for a second or two before the bad sensor shut down the system? Also, as I have mentioned, I heard a "click" that I assumed was the gas valve opening after the ignitors had glowed. Is there any simply way to check if it truly is opening? Thanks


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## kennzz05 (Nov 11, 2008)

flame sensor as you suspect only comes into play after flame has established
as to weather or not its truly opening if you can get to the exaust smell the exaust air for raw gas but i think you mentioned it lights once and awhile so its probably opening
inspect the burners by removeing them could have lint from dryer or such other crap inside which will affect the proper distribution of the gas in the burner and may be preventing it from getting to the ignitor. once removed look down the burner from the oriface end theres a little venturi ring in there that can become dirty


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## yuri (Nov 29, 2008)

Those units can be quite finicky. Check the inlet screen inside the burner box/where pipe attaches (it is there/look closely). May have to call an experienced Carrier tech for more help. If the little red gasket around the base of the igniter is broken air sucks thru there and disrupts the flame. He can check the ohm reading of the igniter and compare it to a new one. Should be between 50-85 ohms. Have him pull/clean the burners and check for power to the gas valve. Pretty complicated/advanced stuff for a DIYer and can be dangerous. Saving a few $$ ain't worth a bigger problem later.


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## cu1982 (Dec 26, 2008)

*Thanks*

Appreciate all the feedback. I'll check the intake screen for blockage, but as you suggested this is rapidly getting beyond my capabilities. Fortunately we have a split zone heating unit so the upstairs will stay warm and we have a downstairs fireplace as a backup. Looks like I'll be calling Carrier service next Monday after they get back in from the Holidays. All just irks me a bit as I am an employee of UTC (parent of Carrier) and I have to admit that these units have not been the most reliable - already had the compressor on the A/C section replaced twice under warranty. C'est la vie.... Thanks again


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## yuri (Nov 29, 2008)

I have worked on a lot of them and from experience learned all those points the hard way. Don't want to comment on Carrier quality, it ain't what it used to be. Unfortunately the guys in the suits don't ask the techs how to build a unit. Costs a lot of advertising $$ to get the name recognition back.


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## cu1982 (Dec 26, 2008)

*Solved*

Just wanted to update everyone on the solution FYI. At Yuri's suggestion, I made a service call to our local Carrier dealer. Got an appt within 36 hours and the tech arrived when he said he would. I walked him through all the diagnostics I had gone through, which he said was quite logical - long story short it was a clogged burner orifice. It was just one out of the three, but the one closest to the igniter. He borrowed a very fine drill bit from me and cleaned out all three injectors. Ran a thorough diagnostic on the pressure switch, manifold pressure and all electrical connections. Worked like a champ on start up, and so far so good. It was actually a pretty easy fix, but great to have pro do a complete check. Bottom line was $150 - a pretty good deal in my estimation.
Thanks to all for the help.


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## yuri (Nov 29, 2008)

Sounds like a good Dealer. Can be hard to find them sometimes. I have never had a clogged orifice. Even a old tech like me can learn something new. Glad you got it going properly and safely.


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