I have a Bryant Plus 90. Model is 350MAV036080 ADKA.A week and a half ago, we woke up to the furnace not kicking on at all. I was getting Code 23, which is the pressure switch not opening. After a long unsuccessful day of fiddling with it, I called a professional and I don't know what all he tried, but he ended up just changing the pressure switch. For the last week and a half, it's worked fine until today. I'm getting a Code 33, which is limit/flame roll out switch is open. The furnace just keeps running the blower with no heat. I forgot to put a filter back in it after the tech came out last week, but I put in a perfectly new, clean filter this morning. There doesn't appear to be a light in the combustion box, but I'm not sure if this model is supposed to have a standing pilot light or not, and I'm not entirely sure how to go about relighting it if it is. Only other thing I can think to mention is there sounds like there's a slight rattling while it's blowing, but it comes and goes.
This Site Might Help You. RE: Bryant gas furnace problems, again? I have a Bryant Plus 90. Model is 350MAV036080 ADKA. A week and a half ago, we woke up to the furnace not kicking on at all. I was getting Code 23, which is the pressure switch not opening. After a long unsuccessful day of fiddling with it, I called a professional and I don't know what all he...
First, shut off the power and restore it after a minute. This may clear the fault and it will retry. If the blower comes on immediately then you do have an open limit that has cut the control voltage. It is normal for the blower to run constantly if a high limit or roll out switch is open. This is to ensure it cools down in an over heat condition. You have to find the open roll out. Some have a little push button in the center and can be reset. Some don't have that. The best way to find it is while it is calling for heat you take voltages across the rollout/limit switches. A closed one (normal) will read no voltage. A tripped, open, switch will read 24 volts across it. That is the one that needs to be reset or replaced if not resettable. That only diagnoses the symptom. What tripped it is another matter. That depends on which one tripped and if it trips again. Good Luck
Bryant Furnace Troubleshooting
Bryant Gas Furnace Troubleshooting
Be aware of the heat exchanger problems on this unit. There has been a class action lawsuit a while back claiming faulty design. Your furnace has a lifetime warranty on the heatexchanger for the original purchaser. If you purchased the home previous from the original purchaser it has a twenty year warranty. The lawsuit resulted in the manufacturer to offer labor to replace the heatexchanger also in the amount of no more than 4 hrs for an approved service company. Also there is the option to replace the unit and receive $400 towards that replacement. You will need to do that with a Bryant dealer. The typical heat exchanger failure will cause pressure switch failures and limit switch trips. The outlet of the vent outside is probably black. If you google carrier heat exchanger class action lawsuit you will find all this info. Bryant and Carrier are made by the same manufacturer.
