HVAC

Have HVAC Questions? Ask an HVAC Expert for Answers

Ask an Expert,
Get an Answer ASAP!

HVAC

JBM. Lennox G26. Furnaces runs normal for approx 30 secs…

Customer Question
Hi JBM. Lennox G26. Furnaces...
Hi JBM. Lennox G26. Furnaces runs normal for approx 30 secs then blower motor stops. Furnace continues to run until limit switch tripped. Throws "Primary/secondary limit switch open" code. I cleaned the flame sensor and installed new limit switch so far.
Submitted: 2 months ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Answered in 38 minutes by:
12/16/2017
HVAC Technician: HVAC Guru, HVAC TECH replied 2 months ago
HVAC Guru
HVAC Guru, HVAC TECH
Category: HVAC
Satisfied Customers: 17,996
Experience: 20yrs in the HVAC industry with certificates and degrees.
Verified

One moment please..Note it takes time to type and add links so please be patient. Also the site will send you a phone call offer, that is not me.

Ask Your Own HVAC Question
HVAC Technician: HVAC Guru, HVAC TECH replied 2 months ago

Can you see what limit is opening?

Ask Your Own HVAC Question
Customer reply replied 2 months ago
I'm not sure how to tell which limit it is. I replaced the temperature limit switch. At first I couldn't get the blower motor to turn on at all, then after reading that it might be the vacuum switch, I blew into one of the vacuum tubes and that seemed to get the furnace running for 30 seconds.
HVAC Technician: HVAC Guru, HVAC TECH replied 2 months ago

This is likely a thermal rollout issue. There are high limit safety thermostats that are around the burner housing area that can trip open if they fail or the unit is overheating. Some of these have reset buttons on them that you can manually press down to reset while others do not. The ones that do not either are one time limits or are limits that are suppose to manually reset when cooled down. Now that does not always happen when they go bad so you will have to check them for continuity with an ohm meter across the two leads going to them. If you do not pwn a ohm meter you can physically bypass each rollout to make sure it is good by connecting the two wires to each rollout sensor together to see if the unit will then operate. Now once you have found the bad one you can change it out or reset it and then you should check your furnace filter for blockages and make sure you main furnace blower is running to speed. These two things can cause a unit to overheat and trip one of these rollout sensors. Mosts units have 3 of these devices and here is a link to what they can look like on your unit.

CLICK HERE

CLICK HERE

CLICK HERE

All I ask is please use the....FINISH BY RATING link at the top your page to select a 5 STAR RATING before leaving today....this is important for my status on the site plus without a rating I will receive ZERO credit(NO PAY) from the site for assisting you. Also rating now does not close the question out and you can come back anytime for FREE right here to me......Happy Holidays!

Ask Your Own HVAC Question
Customer reply replied 2 months ago
I have the first two limit switches. The one with the reset button doesn't push in or pull out so not sure if it is tripped. I did bypass it but furnace still doesn't stay running.
What would happen if the vacuum switch was bad? Would furnace run at all?
Customer reply replied 2 months ago
How do I check if the motor is running to speed? It seems to be running normally.
HVAC Technician: HVAC Guru, HVAC TECH replied 2 months ago

If the pressure switch opened nothing would run. Can you upload a picture of the wiring diagram on your unit here for me to check out?

Ask Your Own HVAC Question
HVAC Technician: HVAC Guru, HVAC TECH replied 2 months ago

Hi there,
I was just touching base with you because I have not heard back from you and the question is still open and unrated, I am not credited anything until a good star rating is supplied I would really appreciate it if you could do that thanks!

Ask Your Own HVAC Question
Was this answer helpful?
Ask HVAC Guru Your Own Question
HVAC Guru
HVAC Guru
HVAC Guru, HVAC TECH
Category: HVAC
Satisfied Customers: 17,996
17,996 Satisfied Customers
Experience: 20yrs in the HVAC industry with certificates and degrees.

HVAC Guru is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future.

JimmyBagley, IA

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

< Previous | Next >

Meet the Experts:

Phil

Phil

Mechanical Engineer

6,938 satisfied customers

Retired HVAC/ Electrical & Boiler contractor. Industrial

Rick Mather

Rick Mather

HVAC Technician

3,133 satisfied customers

35 years experience, HVAC

Matthew

Matthew

HVAC Technician

2,014 satisfied customers

14 years experience in the HVAC field of service, installation, Manual J & D calculations

Kenton Guidry

Kenton Guidry

HVAC Technician

963 satisfied customers

12 years install/service experience.

Brian HVAC Guy

Brian HVAC Guy

HVAC Technician

953 satisfied customers

I have been an HVAC/R mechanic/technician for 30+ years.

Rick Ridley

Rick Ridley

UK Heating Engineer

871 satisfied customers

Retired But have had 30 years on the tools, Ex CORGI

Tom

Tom

HVAC Technician

770 satisfied customers

16+yrs HVAC/R service. Residential Commerical Industrial

< Previous | Next >

Related HVAC Questions
Why is there water under my furnace? Filter is clean and
humidifier is off and not leaking, AC is off, quite cold outside, no snow on chimney… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Rheem furnace blower runs on low but will not run on high
rheem furnace blower runs on low but will not run on high furnace goes off on high heat limit … read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,142 satisfied customers
My Rudd furnace blower vibrates the entire house. Research
My Rudd furnace blower vibrates the entire house. Research indicates a motor/fan set screw may need tightening, but I can't see one. Where is it found? Can it be adjusted without removing the motor?… read more
HVAC Guru
HVAC Guru
HVAC TECH
17,996 satisfied customers
Goodman GVC9 furnace: blower will turn on, but no heat.
Goodman GVC9 furnace: blower will turn on, but no heat. Checked intake and exhaust, they look ok. Flashing code 4 so replaced the filter which needed replacing. Limit switch in middle of unit shows no… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Concord 90 furnace blower runs wont stay lit. I blew out
concord 90 furnace blower runs wont stay lit JA: Did you check the furnace's filters? Customer: yes JA: Do you plan on doing the work yourself? Customer: yes JA: Anything else we should know to help y… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
My RUUD furnace blower is not turning on. The circuit board
My RUUD furnace blower is not turning on. The circuit board says its a "Limit Switch Open" error. How can I fix this?… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
My 59SC2b furnace blower running time and blow cold air
My 59SC2b furnace blower running long time and blow cold air after heating cycle. … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
Luxaire9v serires furnace Blower won't go into second stage.
Luxaire9v serires furnace Blower won't go into second stage. I replaced pressure switch and still no working. … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
Carrier furnace blower fan comes on without heat set point
Carrier furnace blower fan comes on without heat set point being triggered … read more
HVAC Guru
HVAC Guru
HVAC TECH
17,996 satisfied customers
My furnace blower stopped suddenly. I live in about 2,000sq
My furnace blower stopped suddenly. I live in about 2,000sq feet single family home. I called an HVAC technician. They arrived and installed a new motor. However, after they left I run the furnace and… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Have an older luxaire commerical furnace blower motor runs
have an older luxaire commerical furnace blower motor runs all the time … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
My furnace blower wiil not start. Hopefully. Furnace tries
my furnace blower wiil not start JA: Did you check the furnace's filters? Customer: no JA: Do you plan on doing the work yourself? Customer: hopefully JA: Anything else we should know to help you best… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
My evcon furnace blower fan cycles every day at 8:20 with no
My coleman evcon furnace blower fan cycles every day at 8:20 with no demand and no exhaust fan operation. It just co es on runs for 2 minutes then shuts down, and there was no previous heat dema d … read more
HVAC Guru
HVAC Guru
HVAC TECH
17,996 satisfied customers
My Nordyne furnace blower starts immediately when I turn on
My Nordyne furnace blower starts immediately when I turn on the switch. The LED light on the control board flashes 5 times. There is no flame. … read more
Regan Land
Regan Land
General Manager
Vocational, Technical or Trade Scho
508 satisfied customers
My '92 Carrier model 58ssc furnace blower motor has finally
Hi! My '92 Carrier model 58ssc furnace blower motor has finally quit. I wonder what I can replace it with … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
We have a question about a furnace blower that is not
We have a question about a Bryant furnace blower that is not working. The model number is ***** We have noticed a blinking light error that has two short and four long blinks. … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a loud noise coming from furnace blower motor. Do i
I have a loud noise coming from furnace blower motor. Do i need to oil up the motor? Its a lennox g40uh (x) … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I'm replacing a furnace blower motor and assumed it would be
I'm replacing a furnace blower motor and assumed it would be plug and play. Old motor had 5 wires; white, brown, black, red and blue. The brown and white went to the cap, with another white wire comin… read more
Daniel Plourde
Daniel Plourde
plumbing, hvac technichian
Vocational, Technical or Trade School
432 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x