HVAC

Have HVAC questions? Ask an HVAC Expert for answers

Ask an Expert,
Get an Answer ASAP!

This answer was rated:

I have a Goodman furnace. And it's continually blinking.. I…

I have a Goodman...

I have a Goodman furnace. And it's continually blinking.. I was wondering how does it reverse polarity?....

Contractor's Assistant: Did you check the furnace's filters?

Yes

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

Yes. I live to far out of town.

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

Just my light suggests reversed polarity.

Show More
Show Less
Ask Your Own HVAC Question
Answered in 5 minutes by:
3/26/2018
Brian HVAC Guy
Brian HVAC Guy, HVAC Technician
Category: HVAC
Satisfied Customers: 1,024
Experience: I have been an HVAC/R mechanic/technician for 30+ years.
Verified

Hi, I'm Brian and I'll be happy to help with this.

If you haven't had any other electrical problems or electrical work done on your home lately and this problem crept up out of nowhere, it's more likely you have a poor connection somewhere in either the neutral line somewhere in the furnace circuit (internal OR external to the furnace) OR, you have a loose, poor or corroded ground connection within or external to the furnace. This can cause the reverse polarity issue too. The voltage to neutral/ground is looked at as a reference for this in the microprocessor.

Ask Your Own HVAC Question
Customer reply replied 4 months ago
I have no work done. So check ground wires

Yes, I would turn off power to the furnace and check ALL wiring connections withing the furnace, paying special attention to the ground wires and the incoming neutral connection(s). Make sure you check the how the furnace control board is grounded to the furnace chassis and make sure it's a clean tight connection!

Ask Your Own HVAC Question
Customer reply replied 4 months ago
Ok. Can I check back with you after

Yes you certainly can! Please bear with a slow response as I may be assisting other customers at the time you respond.

Thanks and be cautious!

Brian

Ask Your Own HVAC Question
Customer reply replied 4 months ago
Could the problem be in the thermostat?

That is not likely with the reverse polarity issue. You could try disconnecting all wires at the thermostat, tying together the wires that were connected to R and W then cycling the power to the furnace off then on to reset it and see what happens but it's rarely ever a thermostat issue with the reverse polarity fault code. It's generally always a loose or bad wiring connection of ground or neutral in the furnace or a failed furnace control board.

Ask Your Own HVAC Question
Customer reply replied 4 months ago
Spoke to a tech. He was suggesting it could be the igniter. And that it was $90. And very fragile.

Yes, hot surface ignitors are very fragile for sure! Especially after they've been in use. Yes, if the ignitor has failed and is in a ground fault, it could throw that fault too.

Ask Your Own HVAC Question
Customer reply replied 4 months ago
Well. Now I know the problem. I found little metal parts under the igniter. Question? The spots where the sensor and igniter are. Can they be switched around. It would be easier to instal igniter?

Ah, yes there's your ground fault! I've never switched the two around on any furnace. What's the full model number of yours, let me have a look at the service manual and I'll have a closer look.

Ask Your Own HVAC Question

You could also likely get a HSI ignitor online much cheaper than $90. With the model number I can see if I can source that for you too.

Ask Your Own HVAC Question
Customer reply replied 4 months ago
GoodMan model GMS8 0903BNAA motor 1/3hp

Thanks, ***** ***** see what I can find for you. Thanks for your patience!

Ask Your Own HVAC Question

Ok I can see why you'd want to swap places but I wouldn't recommend it. You just have to be careful when you insert the HSI, I've done this one and it's not that tough. I would recommend replacing the flame sensor at the same time anyway. The Ignitor is Goodman P/N 20165703 and Click Here for a good price for it. The flame rod is Goodman P/N B1172606 and Click Here for a good price for that item. You can find both these parts all over the internet, I just found those with a cursory search for the lowest price. Sears was much more expensive for the flame rod.

Brian HVAC Guy
Brian HVAC Guy, HVAC Technician
Category: HVAC
Satisfied Customers: 1,024
Experience: I have been an HVAC/R mechanic/technician for 30+ years.
Verified
Brian HVAC Guy and 87 other HVAC Specialists are ready to help you
Ask your own question now
Customer reply replied 4 months ago
Thank you. You are awesome. Cheers!

You're very welcome! Thanks for the great rating! Best of luck and have a great night!

Best regards,

Brian

Ask Your Own HVAC Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a hvac technicianLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Brian HVAC Guy Your Own Question
Brian HVAC Guy
Brian HVAC Guy
Brian HVAC Guy, HVAC Technician
Category: HVAC
Satisfied Customers: 1,024
1,024 Satisfied Customers
Experience: I have been an HVAC/R mechanic/technician for 30+ years.

Brian HVAC Guy 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

7,634 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

Brian HVAC Guy

Brian HVAC Guy

HVAC Technician

1,024 satisfied customers

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

Kenton Guidry

Kenton Guidry

HVAC Technician

963 satisfied customers

12 years install/service experience.

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
It says that the polarity is reversed and nobody has been
It says that the polarity is reversed and nobody has been inside there. do you think it is the board? I JUST ASKED FOR AWIRING DIAGRAM FOR THE GOODMAN GMP100-3REVA… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
Furnace lights up n then shuts down we notated the led light
Furnace lights up n then shuts down we notated the led light non stop blinking goodman furnace chilly in house … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a forced air goodman gas furnace. The fan come on but
I have a forced air goodman gas furnace. The fan come on but the unit does not blow any air through the system what could be wrong?… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
it's a twinning question. when i plug the wire to the twin
it's a twinning question. when i plug the wire to the twin post on the icm, both furnaces go out, but when i leave the wire off, they lite.… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
What does a continuous steady flashing (no pausing & not rapid
What does a continuous steady flashing (no pausing & not rapid flashing) led light on a Goodman GMS80904BN furnace mean? At heat request, induce motor comes on for about 30 seconds, no glow, then shut… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
I have an Armstrong Ultra V Tech 80 furnace. I just installed
I have an Armstrong Ultra V Tech 80 furnace. I just installed it. Before the gas was connected the hot surface ignitor was coming on periodically. I now connected the gas and the hot surface ignitor i… read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
hi, I have a goodman gmpe 100 furnace. It will sometimes come
hi, I have a goodman gmpe 100 furnace. It will sometimes come on and the gas will also come on. If it does, then within a minute, it will shut off. Also, sometimes there will only be a clicking noise.… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
A/C unit works blows cold, heat system does not. red light
A/C unit works blows cold, heat system does not. red light stays on , no blinking, cleaned flame sensor. What's wrong? Now I tried putting it on AUTO and HEAT and at 90, and the red light blinks const… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
I have a furnace s/nG5R9507-01977 that I changed the 3 amp
I have a furnace s/nG5R9507-01977 that I changed the 3 amp fuse and it just blinks the red light on the circuit board and has a very faint humm… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
We have an American Standard gas furnace, 3 yrs old. The pilot
We have an American Standard gas furnace, 3 yrs old. The pilot seems to be out and I have followed the directions to re start it. It doesn't seem to work. There is a green light showing and a red ligh… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
my furnace flash code is continually flashing. It say either
my furnace flash code is continually flashing. It say either reversed polarity or reversed twinning.… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
i have acarrier gas htr 58pav replaced circuit board last year
i have acarrier gas htr 58pav replaced circuit board last year worked fine went to start this year and blower run but nothing after that cycle red light flashes cont. while blower running… read more
M Oglesby
M Oglesby
Vocational, Technical or Trade Scho
2,010 satisfied customers
I bought an ICM280c furnace control board to replace my b18099-13
I bought an ICM280c furnace control board to replace my b18099-13 control board on my Goodman GMP075-3 furnace and it blinks continuously. I turned off and triple checked the instructions and wiring. … read more
Tom
Tom
HVAC Technician
Vocational, Technical or Trade Scho
770 satisfied customers
I have reversed the polarity of the hot and neutral wire while
I have reversed the polarity of the hot and neutral wire while installing a new Goodman furnace. This has caused the blower to malfunction, with lots of smoke coming out the machine. What damage can r… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,634 satisfied customers
I have a goodman gmp100-3 gas hot air furnace . On your instructions
I have a goodman gmp100-3 gas hot air furnace . On your instructions last week I installed a new circuit board . Worked fine for a week. Not working today. my red light indicator is showing continuous… read more
Regan Land
Regan Land
General Manager
Vocational, Technical or Trade Scho
508 satisfied customers
Goodman model GMH95 furnace. Lost power to unit. Fixed faulty
Goodman model GMH95 furnace. Lost power to unit. Fixed faulty house wiring and now have power to unit but it will not function. ID blower will come on for 15 second purge cycle and then shut off. LED … read more
Matthew
Matthew
HVAC Technician
Bachelor's Degree
2,014 satisfied customers
I have a Model GDT090-4B Goodman Furnace, converted for LP
I have a Model GDT090-4B Goodman Furnace, converted for LP use. When the thermostat is set to cool or off, the status light is constant. When the thermostat is set to Heat the light blinks continuousl… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
I am getting a reversed polarity signal from my gas furnace.
I am getting a reversed polarity signal from my gas furnace. It is a Bryant model #383KAV036370. The panel stated that if it is twinned then see twinning kit instructions. How do I reverse the polarit… 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