HVAC

Have HVAC Questions? Ask an HVAC Expert for Answers

Ask an Expert,
Get an Answer ASAP!

HVAC

My name is
, my furnace is short cycling will not stay

Customer Question
Customer: my name is wes...
Customer: my name is wes
JA: Thanks. Can you give me any more details about your issue?
Customer: my name is ***** ***** furnace is short cycling will not stay on to reach thermostat temp, I show a 4 code on my board,limit switch
JA: OK got it. Last thing — HVAC Technicians generally expect a deposit of about $18 to help with your type of question (you only pay if satisfied). Now I'm going to take you to a page to place a secure deposit with JustAnswer. Don't worry, this chat is saved. After that, we will finish helping you.
Submitted: 1 year ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Answered in 1 hour by:
1/23/2016
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago
Rick
Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 22,407
Experience: 40+ yrs. experience as a licensed oil & gas technician.
Verified

What is the brand and model number of your furnace?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
I'm not sure it has no tag I think it's a Lennox not sure of model has no tags or markings
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

There should be a rating tag inside the burner compartment. Look there

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Sbm14
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

What brand?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Goodman gmp075 3
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

Ok, a 4 blink code is an open limit circuit. The easiest thing is to try resetting the roll out out switch(es) (see attached pic for typical). They are located just outside the burner chamber. Turn the power off to the unit then try pushing the small button between the 2 leads on the switch. If it clicks you have reset it and the unit will fire up when you turn the power back on with any luck. If it doesn't click it wasn't tripped

Ask Your Own HVAC Question
Customer reply replied 1 year ago
There were three switches none were tripped
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

Then you either have a bad limit (the furnace should have cooled down by now) or a bad connection in the limit circuit. You can try checking all the connections on the limit circuit. That would be the wire the rollouts are connected to

Ask Your Own HVAC Question
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

The main limit is on it's own circuit on this model. Red wire. The limit is a rectangular "patch" with 2 terminals located above the burners where it can be inserted into the heat exchnger

Ask Your Own HVAC Question
Customer reply replied 1 year ago
All wires are purple there are 4 total 1 is on blower cage 1 top if heat exchanger then 1 on each side there is also 1 on bottom it is same type if button switch just different reset button one on blower box has no reset button so one or all are bad how do you check?
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

Like I said before the main limit on this model is on a different circuit that the rollouts, it has a red wire. You need a continuity tester to check these devices

Ask Your Own HVAC Question
Customer reply replied 1 year ago
I see it it has a black plastic mounting plate with 2 red wires I don't have my tester with me it's at my shop can I jump them together or should I just wait and test it
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

You can't run the furnace with it jumped out but you could test it. If the furnace doesn't lockout then the limit is probably bad since the furnace must be cold by now or if it locks out after running for a while you could have an air flow problem from a clogged AC coil or a dirty filter.

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Filter is new started there I have never cleaned the bottom side of the A coil I checked the top from access panel but can't see bottom which is where it would be dirty will check it after work tommorow if I can figure out how to get to it
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

ok

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Thanks rick
HVAC Technician: Rick, HVAC Supervisor replied 1 year ago

You're welcome

Ask Your Own HVAC Question
Ask Rick Your Own Question
Rick
Rick
Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 22,407
22,407 Satisfied Customers
Experience: 40+ yrs. experience as a licensed oil & gas technician.

Rick 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

6,730 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
90% secondary heatexchanger holding a lot of water in it,
Bryant 90% secondary heatexchanger holding a lot of water in it, not allowing the pressure switch to close. I removed the 3 hoses at the top (2 large 1 small) of the plastic trap and drained the water… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
Need a heat exchanger for model GIN 80bu-1000 14B-3A; ser. #
need a heat exchanger for model GIN 80bu-1000 14B-3A; ser. # 1607K 03798 … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
In 2003, we had a new high-end Carrier Infinity Weathermaker
In 2003, we had a new high-end Carrier Infinity Weathermaker furnace installed - Model 58MVP-100-20 (run on propane). 8 years later, in 2011 - while still under warranty (parts and labor) the main hea… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a Comfortmaker RPJ II furnace. It won't heat. The
I have a Comfortmaker RPJ II furnace. It won't heat. The induction motor runs and runs. I don't see the ignitor light. But, I don't hear the click before the ignitor should light. Does that mean the p… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
I have a furnace 17 years old. renters say are experincing
I have a bryant furnace 17 years old. renters say are experincing maybe a co2 leak. any advice.… read more
Kenton Guidry
Kenton Guidry
HVAC Technician
Vocational, Technical or Trade Scho
963 satisfied customers
Is it unsafe to have a cracked heat exchange on your
Is it unsafe to have a cracked heat exchange on your furnace? … read more
Rick
Rick
HVAC Supervisor
22,407 satisfied customers
I need a heat exchanger kit for a weil-mclain ultra 105, no
i need a heat exchanger kit for a weil-mclain ultra 105 … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,730 satisfied customers
How do I check heat exchanger for blockage. Today. Sounds
how do I check heat exchanger for blockage JA: I'll do all I can to help. How long have you been dealing with this? Customer: today JA: Do you plan on doing the work yourself? Customer: yes JA: Anythi… read more
Rick
Rick
HVAC Supervisor
22,407 satisfied customers
When were stainless steel heat exchangers required for
When were stainless steel heat exchangers required for residential usage and/or what HVAC company was the first to provide them. And are they as effective as touted.… read more
D.E. Anderson
D.E. Anderson
Industrial Refrigeration Service Manager
200 satisfied customers
Funky smell coming from heat exchanger outside...... repair
funky smell coming from heat exchanger outside...... repair guy said the gas not m ixing with the air properly..true? said probably just clogged … read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
Heat exchanger is a month old and heat stopped working.
Heat exchanger is a month old and heat stopped working. Three lights are blinking saying it is a limit or rollout switch … read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,090 satisfied customers
I have a property with a Keeprite heat exchanger installed.
I have a property with a Keeprite heat exchanger installed. I believe the filter is clogged but I don't know where it's located. The model is PGF018K040E … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,730 satisfied customers
The condensation water leaks from heat exchanger near the
The condensation water leaks from heat exchanger near the filter and comes on the ground tray. There is no blockage of any sort. What needs to be done for auxiliary condensation tray if it is cracked.… read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,090 satisfied customers
How can I clean the inside of the heat exchanger on my
how can I clean the inside of the heat exchanger on my furnace? … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
My carrier heating heat exchanger is plugged. I understand
My carrier heating heat exchanger is plugged. I understand it is civered under a recall action. if bI purchase a new systeem 59mn7a080-20 what price drduction do I receive? … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
How much time should be allowed to change a heat exchanger
How much time should be allowed to change a heat exchanger for a 48tjf016 series 580ba and 2 men?… read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,090 satisfied customers
I have Yorx High efficiency tubular heat exchanger, im not
Hi, my name is***** have Yorx High efficiency tubular heat exchanger, im not sure wich model though GY9S , GM9S, or GF9S. There is water leaking from the white PVC pipes, can I just cut them out and r… read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,090 satisfied customers
I was looking into a trane tud060 heat exchanger and noticed
I was looking into a trane tud060 heat exchanger and noticed a buildup of white powder at one of the factory seams and need to know what is causing this. I attached a pic. Thanks… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 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