Furnace Blinking Error Code - Limit Switch - Carrier WeatherMaker

Update: I replaced the filter and that fixed the problem. Hope this helps and saves you some money.
Here is short video showing how to read the blinking error code on your furnace. Also did a little research on the “Limit Circuit Lockout” to help trouble shoot the problem. Again, error code 13 that referred to error code 33 “Limit Circuit Fault”. Things to clean/replace/check: Air Filter, Proper Vent Sizing, Restricted Vent, Loose Blower Wheel, Excessive Wind, Defective Blower Motor, Defective Switch, Inadequate Combustion Air Supply, Dirty Blower Assembly, and/or Dirty Evaporator Coil. Hope this video helps.

[@josephfryc5994]

I had same issue, my fix was behind the electrical panel not shown here, I don"t know what it"s called but there are hoses connected with wiring. One wire was not connected securely, and that fixed my problem, hopes this helps and Good Luck.

[@huffito22]

So I replaced the filter and it worked for the rest of the winter. I did order the part on Amazon, but the furnace continued to work as long as I changed out the filter regularly. Thanks and hope this video helps!

[@ptg01]

I had code 33 last night.. replaced my one month old filter and voila... all set. Weird as my filters always last me two to three months and filter still looks brand new !

[@firearmconsumertone1]

Thanks I had the same exact problem and this video helped fix mine

[@huffito22]

Awesome, just hoping to save everyone a little $! Thanks

[@AmericanFarmerHVAC2024]

You need to have that furnace checked out. Those models were notorious for cracking the heat exchanger.

[@pcvvalve6139]

I went to a call similar to this last week and it turned out that there was a large couch blocking the return air vent. So the furnace wasn’t getting the adequate amount of air passing through it and got too hot. When it gets too hot the high limit will trip and it will need time to cool down. Also don’t buy pleated filters they are too restrictive but the cheap ones and check it every month.

[@Dadubick]

Good to know! If the furnace is in the basement, where is the return air vent in relation to the unit? Same floor? Upstairs? Thank you.

[@pcvvalve6139]

@@Dadubick Most homes have one on each floor

[@bonkoo5978]

so it has to be long blink and short blink or short blink or long blink right? not short blink, then long blink , then short short ?

[@josefaguevara6159]

Thank you for this video 😊

[@huffito22]

Thank You!

[@icemancometh8679]

My tempstar furnace is six years old and in the attic. It has return air going through a large vent in the ceiling. It acted up by running the fan all night long but not getting up to temperature. Turns out that was probably flame sensor. I cleaned that and then it sent another code that they told me was high temperature limit switch. Someone on line replaced their limit switch and that didn't fix the problem - what else can I try my filter is clean. Had professionals out here today.

[@huffito22]

I’m sorry I can’t help further. I do keep some extra flame sensors on hand. I’ve been surprised by how some work just great and others don’t last very long. I hope everything works out for you.

[@icemancometh8679]

@@huffito22 I had it serviced and they found something wrong, so yeah it's better now.

[@laurak8634]

What ended up being the problem? I have the same error on mine now and what was wrong with yours might be the same with mine.

[@huffito22]

It was what Jesse Vazquez commented, a dirty filter. After I reset it and changed the filter it worked fine for the rest of the winter.

[@kbarb3071]

How do you reset? Turn it off then back on?

[@laurak8634]

@@kbarb3071 yes, mine has something that looks like a light switch that I just turn off then on.

[@huffito22]

@@kbarb3071 I don't know if this matters, but I turned the thermostat down below the temperature in the house, then flipped the switch to turn the furnace off, then back on again. Then I turned the thermostat up to "call" for heat and it worked fine after I changed the filter.

[@dijavu3943]

@@huffito22do you have to do this all the time in order to let your firnace run? Or you are all set after the filter change and the furnace is constantly running once the set temperature is above the room temperature?

[@dustinyamchuk7400]

Will no gas cause 31??

[@sergio74v41]

My heat turns on but blower motor doesnt turn off. Would this b the limit switch?

[@huffito22]

I’ve never had a situation where the blower motor would not turn off, however about a month ago the blower motor would not work, it was an $18 capacitor. Apologies, I don’t know the answer to your question.

[@senorpimps4678]

Yes the rollout switch and the fuse link that goes on it

[@mo4humanity]

@@huffito22is roll out switch different from limit switch? I replaced the air filters and it is still not working. Error code 13 flashing again.

[@TheyStoleMyPants]

Dirty filter? WRONG filter? Dirty A-coil? Dirty blower? Restricted return air? Obstructed exhaust? Gas pressure too high? Square footage?

[@huffito22]

Sorry for the delayed reply, it was a dirty filter.

[@Jessev7742]

Don’t buy a new limit switch, if the filter is dirty that’s probably it

[@jimbarron8688]

Limit switches are inherently reliable. They trip primarily due to air flow issues as suggested by an old filter. A-coil blockages are also common as are blockages in secondary heat exchanges of high efficiency models. Running without any filter causes other parts of the system to become the filter. Your advise is correct and the cheapest. Try it and see.

[@huffito22]

ExcessiveMasterRaider you are correct. It replaced the filter and the furnace worked for the rest of the winter as long as I kept an eye on it.

[@fortysaginaw1512]

I have an old carrier furnace that blinks 3 times quickly then 3 times slower (3 ). ACCORDING TO the rear panel it is the roll over limit switch or lock oout. I tried tsting then by-passing or jumping the switch to no avail as furnace blower just runs continuously. I did replace the unducer motor a year ago. I cleaned out the hvac, new filter, and did what I could. NOTE: The stages of this 80% carrier furnace are = (1) blower (2) inducer (3) ignitor, (4) then gas to burner on furnace, athat point it is supposed to start. ....My problem is that 3 - 3 code - Should i replace inducer motor again and the limit switch?

[@josephmayfield2556]

Try roll out switch