My Carrier 58RAV has and LED code #33 "Limit or Flame Roll Out Switch is Open" Instructions state "Open flame roll-out switch or fuse link, manual reset or replace". Where is this switch located? How do you manually reset it? Thank you

Flame roll out limits are located on the top or sides of the burner compartment. Some older equipment use a fuse link that is nonresettable and has to be replaced.

This depends on the age of your furnace, first look for the roll out switch to be close to the burners, it will have two wires connected to it and between the two wires will be a small pop-up reset mash the pop-up gently and listen for a click.

The limit on older models havea linit on the fire wall, it will have two wires connected to it and on one of the wires about an inch form the limit you will see a small bulge that looks like a small firecracker. To test this limit you just jumper around the firecracker thing. If everything is set for the furnace to run it will start if this is bad. I don't think it is this limit because the furnace is made so that the blower will run all of the time if this limit is bad.

Let me know if my answer helped

Thank you for the responses. Yes, I did locate them (I have two) and they have a reset switch each. I pressed them both and nothing happened. No clicks, no noise, no resistance. Does that mean they are not working properly? My furnace is from 1998. Thank you.

Thank you for the responses. Yes, I did locate them (I have two) and they have a reset switch each. I pressed them both and nothing happened. No clicks, no noise, no resistence. Does that mean they are not working properly? My furnace is from 1998. Thank you.

I don't think you found the right thing if you found two, What I am talking about is a thing that would be in the flame of the burner on the left side if the burner was burning. The screw that holds it in place in under the burner. So look again and see if you can find it.

For whatever it's worth, my furnace appears to have two as well. They're about dime-sized, mounted in a metal sheet, just above either side of the burner assembly. Each has two red wires going into it, with a button in the middle. Pushing the button doesn't click (which may be because mine are bad, perhaps -- I wouldn't be looking at all this if my furnace wasn't complaining about them). One of the almost unreadably small numbers on the two devices is "HH18HA490A", which Google says is a "290F Limit Safety Rollout Switch", here: http://americanhvacparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=LIMD18HA490&Category_Code

If they didn`t click this means that it doesn`t need to be reset. To check them each farther you will need a multimeter to chek them out correctly,, you could pull the wire off and jumper them together as a way to check them out only,, do not run furnace with them bypassed,, they are a safety device

Further Google-ing has confirmed that they'll not click unless they've been tripped, as you said. I found another limit switch hiding in the vent; this one resets automatically. I tested each for continuity with a multimeter, and each showed a closed circuit. Having reassembled all those, I re-read the furnace's list of possible causes for the #33 code, and noticed it mentioned a possibly bad blower motor or capacitor. Hoping the presumably expensive motor wasn't the problem, I removed the capacitor. I assume as with all large-ish capacitors that it was a good idea to discharge it first, which I did with a wrench across the terminals. My multimeter's capacitor tester reported 9.49 microfarads, just within the +/- 6% tolerance from its 10 microfarad list capacitance. Perhaps it dipped out of spec of something long enough to trigger the problem. In any case, I put the capacitor back in, and now the furnace works fine.

I have a carrier 48GS, the furnace blows cold air only, I have reset it and the LED flashes 7 time, I am not sure what is the problem.
Thanks

I have a Carrier 58PAV. It is blinking code 33. Thermostat is blank. I had neglected to change air filter which is consistent with code 33. 3amp fuse is good. Blower runs continuously. What should I look for? Thanks. Dave, cold in Seattle