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I have 30 year old gas furnace (no air conditioner). the…

Hi, i have 30...

Hi, i have 30 year old bryant gas furnace (no air conditioner). the problem is that the fan doesn't stop. searched internet and learned that mostly the problem is with the fan limit switch. however, i can't find such part in this old furnace.

Contractor's Assistant: Did you double-check the thermostat's settings? And what about the filters?

I replaced the filter but it didn't help. thermostat i set to 70 right now. actually, the burner itself operates OK. it detects the temperature and starts but the fan just keeps on running. i had to shot of the switch manually everytimr.

Contractor's Assistant: Do you plan on doing the work yourself?

If possible.

Contractor's Assistant: Anything else we should know to help you best?

Do you know if this old furnace has the "fan limit switch"?

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Answered in 30 minutes by:
11/19/2017
Webb-Guy
Webb-Guy, HVAC Mechanic
Category: HVAC
Satisfied Customers: 3,297
Experience: maitenance tech at casto
Verified

Hello, and welcome to JustAnswer. My name is ***** ***** I will be the one to assist you. Sorry to hear that you are having this trouble. I apologize for the extended wait time you experienced, I've only just come online now and would like to assist you with your question if you are still needing help that is?

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Customer reply replied 7 months ago
ok. let me know if you need more info from me.
Customer reply replied 7 months ago
well, i guess chatting is better so that i can have the information from you in doc.
Customer reply replied 7 months ago
hello?

just one moment please If the site offers the phone call its not from me please disregard it.

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ok now what is the model number of your Bryant furnace?

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Customer reply replied 7 months ago
actually, it's very hard to locate the model. i don't know where to find it. but, it looks like the one in this youtube link. it's has "payne" emblem on the front though.https://www.youtube.com/watch?v=pQtMRjWNWUo

does yours have a tag in the front like this video?

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Customer reply replied 7 months ago
nut it has "payne" on it.

and there is no numbers on it?

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Customer reply replied 7 months ago
no

ok ​your limit switch should be against the back it should have an arch to it with 4 wires coming out of it. (this information is based on the age of the unit you are saying you have. )

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Customer reply replied 7 months ago
arch?
Customer reply replied 7 months ago
it is on the unit or separate?

yes sort of round with an arch in it. It is on the unit itself yes.

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Customer reply replied 7 months ago
do you have any picture or drawing?

well without a model number its hard to pull up which one you have but its like a box looking thing that has a dial on it something similar to this

https://www.searspartsdirect.com/part-number/5D51-35/0042/387.html?utm_source=bing&utm_medium=cse&utm_term=5D51-35&sid=SPDxBING&k_clickID=8487e5ed-41d0-40a2-abe3-0e6cb5dc15fb​

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Customer reply replied 7 months ago
you said it's on the back, not in front?

yes due to the age I believe yours will be located in the back.

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Customer reply replied 7 months ago
hmm. there is no cover i can open on he back. well, sounds like i should find the model first. i will try myself with the info you sent to me then.
Customer reply replied 7 months ago
id you can spend a little more time, i can send you the picture of the front. is it OK?
Customer reply replied 7 months ago
i mean, the inside behind the front cover.
Customer reply replied 7 months ago
you spent pretty good time already so it's ok if you cannot.
Customer reply replied 7 months ago
does it help?
Customer reply replied 7 months ago
hello, are you on line?

sorry I had to step away for a minute we are having a storm and it knocked the power out but its back on now. One minute.

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Customer reply replied 7 months ago
uh ok.

ok ​so that is your gas valve is that a black box behind that though? That sort of looks like your fan switch from what I am seeing behind what you just sent me.

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Customer reply replied 7 months ago
let me check.

what is with the cord hanging at the bottom? It looks like your glow plug? Has someone else been working on this unit? It looks like it may have been stuck up there to rig it at some point.

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Customer reply replied 7 months ago
there is a black plastic panel screwed to the wall of the unit. two wires are coming out of it. if i unscrew, maybe, a box (you mentioned) may be in it. as for the cord, i have no idea. what is the white knob. on the top of the valve? i can turn it. does it control the gas flow?

yes it controls the gas.

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Customer reply replied 7 months ago
ok. i will try to unscrew the black panel tomorrow and see what's inside.

sounds good it should be the fan limit switch

My goal is to give you the best experience possible! I hope I have earned a 5 star rating! Please remember to rate my service by selecting the 5 stars at the top of the screen before you leave today. If you need more assistance, please use the reply box and let me know.

Webb-Guy
Webb-Guy, HVAC Mechanic
Category: HVAC
Satisfied Customers: 3,297
Experience: maitenance tech at casto
Verified
Webb-Guy and 87 other HVAC Specialists are ready to help you
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Customer reply replied 7 months ago
ok. i'll give you 5 stars. ad, if i have further questions, i will contact you again. thx.
Customer reply replied 7 months ago
Thanks for the follow-up. i think i found the limit switch. i ordered it from eBay. if i have further question when i install it, i will contact you again.
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