I spent several hours trying to diagnose a problem with a Carrier Weathermaker 9200 60000 btu/h furnace. There are extra strong exhaust fumes coming out the concentric vent on the outside and the furnace does not kick out on the pressure switch. However, the burner compartment gets real hot and the burners kick out on either a high limit or a flame roll-out (fault code 33). I have pretty well eliminated a restricted air flow or a restricted vent (unless it is inside the heat exchanger). The flames start to flicker and bounce when the main blower kicks on. I'm suspecting a cracked or leaking heat exchanger. Has this been a problem with this model of furnace, and how can I be sure if that is the problem?
Best wat to visually check the secondary is to pull the inducer off and look at the secondary. If the white polypropylene lamination is flaking off it's junk. :thumbsup::yes:
I took the burner compartment off and looked inside the primary cells the best I could with a flashlight through the small holes for the in-shot style burners and couldn't see any cracks but there was some rust and I thought there could be a rusted seam that might be leaking. I also removed the blower and cleaned it thoroughly and used a small soft brush to get some of the dirt and lint off the secondary heat exchanger. I wasn't really looking for moisture on the heat exchanger at the time but I did notice the blower compartment was pretty wet around the bottom and was starting to rust. The owner had told me about a problem that he had to fix with a clogged drain trap in the furnace a few weeks earlier so I never really thought too much about finding moisture in the blower compartment. However, now that you mentioned it, it makes me think that it is possible that the moisture could be coming from the secondary heat exchanger. The owner is going to have someone with more experience look at it and I agreed. This is a very serious problem if what I suspect is right, but on the other hand it would be a very expensive mistake on my part if I am wrong and sold him a new furnace if his heat exchanger is not the problem.
In the mean time the furnace is shut down until it can be fixed.
Thank you for your input.
River Camper
What I have noticed with Carrier high efficient heat exchanger replacements: 5 years old or less, only the secondary needs to be replaced. >5 years, both primary and secondary are toast. In all of them the trap is plugged, most of them the relief port tube is soft (feels like a thin-walled rubber hose), and most need a new cold spot baffle. If you're replacing both HEs, all the heads of the screws on the primary cell outlet panel are most likely rusted and round, so bring a new primary cell outlet panel to save time trying to remove these (they also have the gasket glued to it, so you don't have to position the new ones, saving you a little more time, lol).
When the new HE is in place, the drain trap has been cleaned, and you are firing up the unit, check the manifold pressure. I find that it's most often overfired (sometimes as much as 4"wc!), but when the manifold pressure is correct, I also find that it's overfired when I clock the meter (gotta clock the meter).
Check with the HVAC company that is checking on it, but I have similar problems with my 9200, I get a pressure sensor fault code 31. I checked with Carrier and there is a 20 year recall on the heat exchangers of certain models of the 9200, which would basically cover the labor of this being replaced, you would just have to cover the cost of the part. The HVAC company should just waive the labor charges as they are being reimbursed by Carrier.
Actually if that furnace is less than 20 y/o the part and labor should be covered under Carrier/Bryant/Payne bulletin (not recall). You might have to pay a small nominal Warranty processing charge. That should not exceed $100
Can you send me a link to this info, last time I called Carrier they told me only labor was covered and the HVAC company agreed. I think I do have a heat exchanger problem so if you can tell me where to find the bulletin it would be of great help, my unit is about 17 years old.
I have a similar problem and will need to replace my furnace. Probably both heat exchangers are going on mine because there is condensation in the furnace AND a contractor came over yesterday and showed me a vertical crack at least an inch long in the primary heat exchanger. The sour smell and the ongoing problem of the burners cutting off (and the non-stop fan after the burners rightly cut off) were also signs of trouble.
Under the suit--as far as I can tell AND from talking with a Carrier representative at the "Enhanced Warranty" number I got--the primary heat exchanger will be provided at no cost BUT you have to pay the labor for it to be replaced. If only the Secondary Heat Exchanger goes, Carrier essentially pays parts AND labor to have it reinstalled. Or you can get a credit for a replacement Carrier furnace.
In my case, as I've seen a crack in the primary heat exchanger, I am now considering what new furnace to get and using space heaters in the meantime. Best of luck.
One test I do is to check the inducer air out put remove the PVC out put pipe from inducer power up the inducer check air out put if you have low air flow remove inducer assembly from unit. Power up the inducer check air out put again. if you have A big improvement in air flow. You have A restriction in the secondary heat exchanger. If you do not have A big improvement in air flow You have A inducer problem
99% of the time if you have A roll out switch is popping out it's A secondary heat exchanger restriction
manometer Yes But no need to night and day difference in air flow
99% of the time if you have A roll out switch is popping out it's A secondary heat exchanger restriction
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
DIY Home Improvement Forum
3.1M posts
319.6K members
Since 2003
A forum community dedicated to Do it yourself-ers and home improvement enthusiasts. Come join the discussion about tools, projects, builds, styles, scales, reviews, accessories, classifieds, and more! Helping You to Do It Yourself!