HVAC

Have HVAC Questions? Ask an HVAC Expert for Answers

Ask an Expert,
Get an Answer ASAP!

HVAC
This answer was rated:

I have a Weil McLain cg 4 natural gas furnace, the pilot…

I have a Weil...

I have a Weil McLain cg 4 natural gas furnace, the pilot stays lit all the time but the furnace doesn't start

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

The pilot is lit, but doesn't turn off even when the automatic damper cycles

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

Yes, I have two of these furnaces, and have worked on them before

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

I am thinking the Mercury flame sensor or the main gas valve may be bad, even when I turn the gas valve to off on the unit, the pilot stays lit, the only way to shut off the pilot is to shut off the main

Show More
Show Less
Ask Your Own HVAC Question
Answered in 2 hours by:
11/11/2017
Daniel Plourde
Daniel Plourde, HVAC Technician
Category: HVAC
Satisfied Customers: 429
Experience: I've been in the HVAC buisness since 2008 working on residential, commercial, and industrial buildings
Verified

hi i am dan i can help you with this. from the testing that you have done it sounds like the gas valve is your problem, especially since when you turn the nob to off the pilot stays on that is an indication that something internal in the valve is broken and stuck on pilot mode. i would recommend replacing the gas valve. if you have any more questions about this please let me know or if this helps you i would appreciate it if you could rate me on my service by selecting one of the 5 stars on your page.

Daniel Plourde
Daniel Plourde, HVAC Technician
Category: HVAC
Satisfied Customers: 429
Experience: I've been in the HVAC buisness since 2008 working on residential, commercial, and industrial buildings
Verified
Daniel Plourde and 87 other HVAC Specialists are ready to help you
Ask your own question now
Customer reply replied 3 months ago
Hi Dan, I believe you are right, I tried " rapping" on the gas valve, and the furnace started! Are there any serviceable parts inside the valve that could be causing the problem?

unfortunately there are no serviceable parts to the gas valve. whenever they are bad it requires replacing the whole valve.

Ask Your Own HVAC Question
Ask Daniel Plourde Your Own Question
Daniel Plourde
Daniel Plourde
Daniel Plourde, HVAC Technician
Category: HVAC
Satisfied Customers: 429
429 Satisfied Customers
Experience: I've been in the HVAC buisness since 2008 working on residential, commercial, and industrial buildings

Daniel Plourde 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
I have a new Rheem 95P single stage natural gas furnace and
I have a new Rheem 95P single stage natural gas furnace and I'm getting a code 56, not listed in the manual. … read more
Regan Land
Regan Land
General Manager
Vocational, Technical or Trade Scho
508 satisfied customers
I have a ruud ultra series natural gas furnace. it will not
i have a ruud ultra series natural gas furnace. it will not light the burner when it tries. it is flashing code 45. what it wrong … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a Rheem classic 90 plus natural gas furnace that is
Hi, I have a Rheem classic 90 plus natural gas furnace that is not properly igniting. … read more
Regan Land
Regan Land
General Manager
Vocational, Technical or Trade Scho
508 satisfied customers
Ruud rgrc07erbgs natural gas furnace wont recognize flame
ruud rgrc07erbgs natural gas furnace wont recognize flame after cleaning flame senser … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Have Ruud natural gas furnace and the gas valve opens after
Have Ruud natural gas furnace and the gas valve opens after the purge does its thing and only stays on for approx 3-5 seconds. Then goes off. The flame rod sensor light never comes on. Changed the rod… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a Payne Forced air Natural gas furnace with a
I have a Payne Forced air Natural gas furnace with a condenser pumo on the side. the pump will not shut off. … read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
Natural gas furnace: Conquest 80 Circuit board: Honeywell
Natural gas furnace: Conquest 80 Circuit board: Honeywell S9200U1000 Universal Hot Surface Ignition Integrated Furnace Controlfurnace shut of itself after around every 20 minutes, although still under… read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,142 satisfied customers
Natural gas furnace exhaust vent has a strong propane ordor.
natural gas furnace exhaust vent has a strong propane ordor. nothing is smelled inside the house … read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,142 satisfied customers
I have a Weil McLain cg 4 natural gas furnace, the pilot
I have a Weil McLain cg 4 natural gas furnace, the pilot stays lit all the time but the furnace doesn't start … read more
Daniel Plourde
Daniel Plourde
HVAC Technician
429 satisfied customers
Hooking up a nest thermostat, I have natural gas furnace set
Hooking up a nest thermostat, I have natural gas furnace set as emerg heat on my old thermostat, main heat set as heat pump. Always Used emerg heat. Of course a/c. I have every wire hooked to my nest … read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I have a 19 year old Nordyne natural gas furnace. This past
I have a 19 year old Nordyne natural gas furnace. This past winter it was intermittent in igniting the gas. The first thing I did was replace the igniter. That did not clear the issue. … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I've got a Carrier 17C natural gas furnace. We just replaced
I've got a Carrier 17C natural gas furnace. We just replaced the blower motor, and now the furnace won't heat the building. The inducer motor comes on, pilot fires, but no main burner. It fired up cor… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
Model p2mp014m08001a natural gas furnace will run about 4-5
model p2mp014m08001a natural gas furnace will run about 4-5 minutes then flame will go out. stat not satisfied. flame sensor good. filter clean … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
My carrier natural gas furnace is short cycling. Thermostat
everything seems to work, as soon as the circ fan starts, it shuts down the burners. Fan operates until it cools down then restarts… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
I need to replace natural gas furnace main valve V804
I need to replace natural gas furnace main valve V804 24V60hz-0.2A class 2 transe what valve will replace this valve… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
I have a natural ga furnace F80A100-3 Fedders It starts and
I have a natural ga furnace F80A100-3 Fedders It starts and cycles properly thru a few cycles then shuts down with an error code of four flashes … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
Heil Natural Gas Furnace won't light. Has a spark gap
Heil Natural Gas Furnace won't light. Has a spark gap ignition that appears to be functioning normally. There appears to be gas flowing from the pilot tube but the spark never creates a pilot flame. I… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I have a problem with my natural gas furnace. I believe the
I have a problem with my natural gas furnace. I believe the furnace is from Clarke Brothers. It is model CMD100NH4R. It uses a Honeywell ST9141A1002 electronic fan timer.Right now it seems like maybe … 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