HVAC

Have HVAC questions? Ask an HVAC Expert for answers

Ask an Expert,
Get an Answer ASAP!

What does error 90 mean on a Trane thermostat?

Regarding the error code 90, there are hundreds of them for Trane systems and they change for each model and year over the decades. About half the time the error code is useful, the other half of the time it’s too vague to be useful or simply wrong.

 

We can discuss this. It will help if you can give me the Model number from the Trane unit that sits outside, and Trane unit that sits inside. (furnace or air hander) and the approximate age of the system, and how it is performing or not performing.

 

 

Read full interaction below »
Ask Your Own HVAC Question

Resolved Question:

What does  error 90 mean on a Trane thermostat?

Submitted: 6 years ago.
Answered in 22 minutes by:
7/26/2012
HVAC Technician: Phil, Mechanical Engineer replied 6 years ago
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7,426
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified

Regarding the error code 90, there are hundreds of them for Trane systems and they change for each model and year over the decades. About half the time the error code is useful, the other half of the time it’s too vague to be useful or simply wrong.

We can discuss this. It will help if you can give me the Model number from the Trane unit that sits outside, and Trane unit that sits inside. (furnace or air hander) and the approximate age of the system, and how it is performing or not performing.

.

Ask Your Own HVAC Question
Customer reply replied 6 years ago
xl20i
HVAC Technician: Phil, Mechanical Engineer replied 6 years ago

That appears to be a water source heat pump.

If it not cooling or heating at all, the error code is likely a high head pressure or low back pressure switched tripped, due to a vapor locked ground loop.

.

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
I need to know what error code 79 on a Trane ComfortLink II
I need to know what error code 79 on a Trane ComfortLink II Thermostat means? … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
My trane thermostat shows an err 163, what does it mean.
My trane thermostat shows an err 163, what does it mean. … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
What doe it mean on our thermostat error code 108, just the
What doe it mean on our thermostat error code 108 JA: Just to clarify, do you think this is a larger HVAC problem, or something specific to the thermostat? Customer: just the thermostat JA: Do you pla… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
I have a complete Trane A/C & electric heat. My thermostat
I have a complete Trane A/C & electric heat. My thermostat reads error code 156. Plus a lite came on the thermostat upper right hand corner. I have a service contract with Advanced Air who I purchased… read more
HvacmanSean
HvacmanSean
Owner
HVAC
233 satisfied customers
i have error code 91 then error code 91 on programmable trane
i have error code 91 then error code 90 on programmable trane thermostat. what can i do? i removed the thermostat and could not find any loose wiring. i went if the attic and the air handler sounds as… read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I have a trane XR80 ac/heating unit. The ac failed to turn
I have a trane XR80 ac/heating unit. The ac failed to turn on so I looked at the unit and there is a steadly blinking red light. After a few minutes the ac turned on but the light is still flashing. W… read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
Trane XE 90 blower runs constantly with a 5 flash code
I have a Trane XE 90 the blower stays on all the time with a 5 flash code the blower comes on with the thermostat wires removed.… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
What is Error Code 126 on Trane Comfort Link II thermostat?
What is error code 126 on Trane comfort link ii thermostat controlling xl20I heat pump? Optional Information: Make : trane Model : xl20i heat pump, comfort link ii thermostat error 126… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
Trane furnance - blinking red light - three times - says inducer
Trane furnance - blinking red light - three times - says inducer error - what does this mean?… read more
M Oglesby
M Oglesby
Vocational, Technical or Trade Scho
2,010 satisfied customers
I have a trane ac and heating system with a trane XL900 thermostat.
I have a trane ac and heating system with a trane XL900 thermostat. The thermostat seems to be not working....... First thing I noticed is that the screen was illuminated when no one had touched it. I… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
I have a model XE1200 Trane heat pump with T8411R Honeywell
I have a model XE1200 Trane heat pump with T8411R Honeywell thermostat. It is 10 years old. I would like to have a "remote control" type of thermostat...I'm just getting lazy in my old age and would l… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
I have a Trane 20i 5ton unit. The thermostat first said error
I have a Trane 20i 5ton unit. The thermostat first said error 104 and now says error 90. of course no cooling. please help… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
Trane XL 16 i thermostat is flashing an error code 80 message.
Trane XL 16 i thermostat is flashing an error code 80 message. What does this mean and what do we do to fix it… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
My Trane XV-90 furnace does not complete a cylce after being
My Trane XV-90 furnace does not complete a cylce after being programmed down for several hours at night. When it re-cycles, the draft motor comes on, the ignitor lights and the burner valve opens for … read more
Heath
Heath
Vocational, Technical or Trade Scho
1,002 satisfied customers
The ignition blower doesnt shut off after heat cycle Burner
The ignition blower doesn't shut off after heat cycle Burner and Circulation have quit. This keeps the next cycle from occurring. Sometimes shutting off the power to the furnace and turning it back on… read more
Heath
Heath
Vocational, Technical or Trade Scho
1,002 satisfied customers
Error code 53 on Honeywell thermostat. What does it mean?
I have a Honeywell VisionPro IAQ "thermostat". It is blinking error code 53, what does that mean? Prior to the error code, the external thermometer was reading 127 degrees, it is in the low 70's… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
I have a Trane TCONT800 Programmable Thermostat and it shows
I have a Trane TCONT800 Programmable Thermostat and it shows "ERROR 126." The heat does not appear to be running properly. Can you explain what this error code means, and where I can find information … read more
Bill
Bill
High School or GED
318 satisfied customers
I have a payne heatpump that was added to my existing Propane
I have a payne heatpump that was added to my existing Propane (Trane) Furnace. I have a Egde thermostate and am getting an error message and have no heat....(E1) is the error message. What should I do… read more
Matthew
Matthew
HVAC Technician
Bachelor's Degree
2,014 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