HVAC

Have HVAC questions? Ask an HVAC Expert for answers

Ask an Expert,
Get an Answer ASAP!

I have a Lennox model 51M 39 thermostat installed with a new…

Customer Question
I have a Lennox...

I have a Lennox model 51M 39 thermostat installed with a new Lennox system when our house was built (01/2011). The screen display died & the system won't operate now. Is there a battery that can be replaced or do I need to replace the thermostat. If I need a new thermostat do you have a suggestion as to a model (we're retired & don't do the wifi stuff). Thanks for your help.

Contractor's Assistant: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat?

Pretty sure its just the thermostat.

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

Probably if its a straightforward swap out of the thermostat; i can read a wiring diagram & replaced the old thermostat in our old house with a programmable one successfully.

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

Don't think so. I'd prefer a model with touch screen rather than buttons like this one has; a little tough to read.

Submitted: 11 months ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Answered in 8 hours by:
9/19/2017
HVAC Technician: Regan Land, HVAC Technician replied 11 months ago
Regan Land
Regan Land, HVAC Technician
Category: HVAC
Satisfied Customers: 768
Experience: Over 20 years of experience, NATE Certified, Licensed HVAC Contractor, Certified IAQ Specialist
Verified

Hello and welcome to Just Answer. My name is ***** ***** I'll be happy to assist you today. There is not a battery in that thermostat unfortunately, but before we call it a bad stat we need to check and make sure there is power getting to the thermostat from the indoor unit. Before we begin let me ask a few questions:

  1. Do you feel comfortable removing the face of the thermostat to expose the wiring? This is low voltage and won't hurt you.
  2. Is the indoor unit accessible?
  3. Do you have a gas furnace or electric air handler?
Ask Your Own HVAC Question
HVAC Technician: Regan Land, HVAC Technician replied 11 months ago

I never received a reply, so I'm just checking in - Would you like to continue?

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 Phil Your Own Question
Phil
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7,426
7,426 Satisfied Customers
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial

Phil 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

7,426 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
Our current HVAC UNIT is 16 years old, time to replace it in
Our current HVAC UNIT is 16 years old, time to replace it in a tough environment – a loft, in a tight location with 10 other condo units. We live in Baltimore . Recommended replacement is a Carrier Gr… read more
HvacmanSean
HvacmanSean
Owner
HVAC
233 satisfied customers
I have just installed Lennox Xc16 3 ton and SL280V furnace.
I have just installed Lennox Xc16 3 ton and SL280V furnace. I am appalled at the size and appearance of the icomfort thermostat. The lcomphLanh … read more
HvacmanSean
HvacmanSean
Owner
HVAC
233 satisfied customers
We have a lennos new air conditioner (2 years) and it was
We have a lennos new air conditioner (2 years) and it was recently maintained. Tiday it's not cooling although the system says it is and no error code comes on the screen … read more
Regan Land
Regan Land
HVAC Technician
768 satisfied customers
Need to replace Nordyne 903992 with higher quality perhaps a
Need to replace Nordyne 903992 with higher quality perhaps a Honeywell theromstat ours lacks sensitivity and has no temp read out Would like a non-programmable wifi model any suggestions ? … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
I have a Lennox furnace Model G40UH -36B-090-15; Serial
I have a Lennox furnace Model G40UH -36B-090-15; Serial Number 5910F14553; the circuit board has these numbers up the left side 100973-01 1710N102559 1012-969. The furnace was installed December 2011 … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I am trying to connect my wifi honeywell tstat, have
I am trying to connect my wifi honeywell tstat, have connected the wires to the correct terminals. I have the system set to heat and the condenser is kicking on. There are three zones in the house and… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
We have a Carrier Comfort Zone II system with 4 zones. Zone
We have a Carrier Comfort Zone II system with 4 zones. Zone 4 shows blank on the current temp and the system keeps running non stop. The other 3 zones work fine. Is this a thermostat failure? Or somet… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
My thermostat on lennox touch screen says system is waiting.
my thermostat on lennox touch screen says system is waiting. what does that mean? i have wifi connection. how do i get air to turn on? we just installed this in September.… read more
D.E. Anderson
D.E. Anderson
Industrial Refrigeration Service Manager
200 satisfied customers
I am looking at purchasing a Honeywell Wifi thermostat JA:
I am looking at purchasing a Honeywell Wifi thermostat … read more
HvacmanSean
HvacmanSean
Owner
HVAC
233 satisfied customers
I have a carrier comfort zone ii thermostat that is
I have a carrier comfort zone ii thermostat that is connected via a V+ and VG wire on my vacation rental. I would like to replace this unit with a wifi enabled unit. What are my options, or who do I n… read more
HvacmanSean
HvacmanSean
Owner
HVAC
233 satisfied customers
The ritetemp thermostat is not functioning and I want to
The ritetemp thermostat is not functioning and I want to replace it but there is no model number anywhere.. I do have serial number only please advise… read more
Brian HVAC Guy
Brian HVAC Guy
HVAC Technician
High School
1,024 satisfied customers
I would like to wire a Honeywell RTH6500wf wifi thermostat
I would like to wire a Honeywell RTH6500wf wifi thermostat to a EWC-ST-2E/EWC-ST-3E series ULTRA-Zone Control Panel.… read more
Daniel Plourde
Daniel Plourde
plumbing, hvac technichian
Vocational, Technical or Trade School
463 satisfied customers
I have a honeywell 32207501-002 Rev thermostat. Some days
I have a honeywell 32207501-002 Rev B thermostat. Some days the a/c will come on other days it may take hours for it to connect to the condenser (fan is working all the time) to cool the house and oth… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
My Honeywell thermostat went out and i had to replace the batteries.
My Honeywell thermostat went out and i had to replace the batteries. The thermostat now works but the ait won't come one. I turned the system off and left off for 10 min but it still won't come on. Is… read more
Stingray
Stingray
3 satisfied customers
I have a newly installed XC21 A/C unit and the iComfort wifi
I have a newly installed XC21 A/C unit and the iComfort wifi controls. New companion lennox air handler too but I don't recall the model. The iComfort connects to the house wifi just fine and seems to… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
The touchscreen on my Honeywell Thermostat died. The system
The touchscreen on my Honeywell Thermostat died. The system still works, I just cannot change the settings. Inside, a stick on label says TH8320U1008. When I type that number into Amazon, a slightly d… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a Honeywell TH9421C1004 Visionpro IAQ Thermostat
I have a Honeywell TH9421C1004 Visionpro IAQ Thermostat installed on my heating/AC system, The system is a hybrid heat-pump/gas heat system with an electronic air filter and a whole-house humidifier. … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
HVAC Issue - No Power to System Last night I went to replace
HVAC Issue - No Power to System? Last night I went to replace my existing programmable thermostat, which was working but wasn't accurately reading the room temperature, with a new one. I turned off th… 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