HVAC

Have HVAC Questions? Ask an HVAC Expert for Answers

Ask an Expert,
Get an Answer ASAP!

HVAC

I have a trance xl80 that won't ignite. Small fan blows,

Customer Question
I have a trance xl80...
I have a trance xl80 that won't ignite. Small fan blows, igniter glows read but has value doesn't open. I checked that gas is flowing on other appliances. I get the 2 flashes flash code. This has happened before, a year ago and then just two weeks ago. Each time unplugging the three position plug on the gas valve worked to get everything going but won't now
Submitted: 1 year ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Answered in 3 minutes by:
12/10/2016
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago
BillyHvac
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22,894
Experience: Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics
Verified

Hello,

Unfortunately this is a fairly common fault.

The board is flashing ignition failure because it thinks it has sent power to the ignitor and then to the valve, but there is no flame.

It ia always one of 2 items....it is the board thinking it sent 24v to gas valve but actually did not...or the board did send 24v to valve but the valve is bad.

It is more commonly the valve on this unit but the 24v test tells for sure.

Valve gets 24v but doesnt open = valve

No 24v =bad board

Billy

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Which wires do I need to check to determine if the 24v is being sent
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

do you have the TUD or TDD?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Sorry not sure what either is
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

the model number...the XL is just a series...there is a model num ber on a tag inside the furnace

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Tdd
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

Thank you...then 2 of the 3 wires to valve are red and black?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
I've got a red and gray coming from the board and a brown coming from pressure sensor
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

Ok so your unit is older than 5yrs then?

Ask Your Own HVAC Question
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

Ok lets back track a little...do you have 2 pressure switches?

I would like to do a test if you game for a hands on test?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
there are two sensors. I'll do everything I can to get the heat on.... dinner party starting in two hours...
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

ok turn power off and take the wires off the pressure switch. Shoild be 2 browns on one side and a orange on the other..correct?

Ask Your Own HVAC Question
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

this will move quicker now that I know you have a 2 stage..

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Just on the one sensor with the two brown and one orange? It's marked P01 HI
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

we want to take the wires off

start furnace

And AFTER the exhaust fan starts connect the wires direct together...a short wire shaped in a U works well for sticking in the wire end connectors.

Then tell me code..

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Working on that now
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

standing by

Ask Your Own HVAC Question
Customer reply replied 1 year ago
it hasn't behaved any different and code is still 2 flashes, no flame
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

thank you...now put those wires back...and do the same thing to the other pressure switch

Ask Your Own HVAC Question
Customer reply replied 1 year ago
On it
Customer reply replied 1 year ago
far nothing new. Just waiting it to go through all the cycles
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

understood....at any time has the gas valve clicked?

Ask Your Own HVAC Question
Customer reply replied 1 year ago
I've only really heard clicks from the board. I think I can hear a small humm at the value for a few seconds. Just got the same code
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

Thank you.

Well we took the entire pressure circuit out of the picture...which puts us back to the valve issue.

You can unplug the 3 wire plug and put meter lead black to a ground and meter lead red to the black during ignition...you will only see voltage for 3 seconds...then test the gray and brown the same way...during the glow it will be energized for 3 seconds..

no 24 on any wires = board

24 on any wire = bad valve

Ask Your Own HVAC Question
Customer reply replied 1 year ago
I only have red, light gray and brown. Set the meter to 200 D.C.?
Customer reply replied 1 year ago
I have 20 then 200
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

we want ac volts~

Ask Your Own HVAC Question
Customer reply replied 1 year ago
K
Customer reply replied 1 year ago
Got over 24v on the red wire
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

thank you..you just confirmed bad gas valve.

Ask Your Own HVAC Question
Customer reply replied 1 year ago
Dang. You wouldn't happen to have the PN would you?
Customer reply replied 1 year ago
It did this just last weekend and started working fine after I messed with it. Any tricks to limp through tonight
HVAC Technician: BillyHvac, Journeyman HVAC Tech replied 1 year ago

I have wedged tooth picks...tapped with hammer...depends if the there is a connection bad, poor solenoid etc.

See here

Ask Your Own HVAC Question
Ask BillyHvac Your Own Question
BillyHvac
BillyHvac
BillyHvac, Journeyman HVAC Tech
Category: HVAC
Satisfied Customers: 22,894
22,894 Satisfied Customers
Experience: Endorsed for unlimited heating, cooling, oil burners, boilers, refrigeration, hydronics

BillyHvac 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 cannot find ANY installation videos that match my
Hi....I cannot find ANY installation videos that match my Honeywell RTH22B thermostat that I just bought. I don't understand how to get the wires into the black part … read more
David Bowden
David Bowden
Owner
473 satisfied customers
My Ruud water heater is leaking from the pressure valve on
My Ruud water heater is leaking from the pressure valve on top of the tank. The power is off. Earlier I flushed the tank, but not very good. Now when I turn on the main water valve to the tank I notic… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a 394gaw furnace the main burners light, stay lit for
I have a Bryant 394gaw furnace the main burners light, stay lit for 30 seconds then go out the pilot stays lit the whole time … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
No power to themostat. Breakers ok. Fuse OK with FAU in
No power to themostat. Breakers ok. Fuse OK with FAU in attic. Could problem be at A/C condenser located outside? Is there fuse located with Condenser outside that could be blown causing the thermstat… read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I have a Rheem Classic Super Quiet 80 that just stopped
I have a Rheem Classic Super Quiet 80 that just stopped heating our house this am. We had 40mph gusts today and I suspect they blew the pilot light out.… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
My problem is with an old amana central heater i cleaned the
hello my problem is with an old amana central heater i cleaned the sensor and replaced the H.S. igniter it heats up when turned on but doesn't ignite then it turns off. the fan continues to blow. … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I need a replacement gas valve for model 7656f859. I am a
I am a gas service tech who trouble shot the unit last week. … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
MY lennox elite series model C26-41FC-1 blower will not
MY lennox elite series model C26-41FC-1 blower will not engage … read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,142 satisfied customers
I've recently installed a HM700A1000 steam humidifier and
I've recently installed a HM700A1000 steam humidifier and everything is working fine except that it's not shutting off. It has the yellow LED constantly on which indicates the water level is to high w… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have a Honeywell he 311 and it keeps going off the purge
I have a Honeywell he 311 and it keeps going off the purge light stays on for a few then off and the machine never goes on … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
Have a carrier thermostat. Fan is working. However I'm
Have a carrier thermostat. Fan is working. However I'm unable to set a temperature and the heat won't come on. Has an error saying HP … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
Trying to add Aprilaire 600M to Lennox furnace with iComfort
Trying to add Aprilaire 600M to Lennox furnace with iComfort tstat. … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
Yesterday we completed installing a Goodman 60,000 BTU
Yesterday we completed installing a Goodman 60,000 BTU 80%eff furnace, brand new or if the package. It fired right up. Turned it off for the night after turning up to 80 to get s blast of heat before … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
I recently bought a property that has a programmable
This is ***** *****. I recently bought a property that has a white rogers programmable thermostat, and I don't know how to operate it. It is a 1F81-261. Do you have instructions? … read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
How to install the Rinnai direct vent wall furnace. I.
how to install the Rinnai direct vent wall furnace … read more
Gaztech
Gaztech
Technician
Vocational, Technical or Trade School
1,142 satisfied customers
I have a TH8000 Series programmable thermostat now. The
I have a TH8000 Series programmable thermostat now. The clock is all wrong. I'm thinking of a wiFi programmable thermostat. but having a problem with what is compatable. can you advise? Thanks Jerry … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Installed new Goodman split heat pump outdoor unit runs even
Installed new Goodman split heat pump outdoor unit runs even with all low voltage disconnected … read more
Iohn Keffer
Iohn Keffer
HVAC Tech
Associate Degree
41 satisfied customers
Well j, Well just replaced a motor, No never dealt with you
Well j JA: I'll do all I can to help. How long have you been dealing with this? Customer: Well just replaced a motor JA: Do you plan on doing the work yourself? Customer: No never dealt with you befor… read more
BillyHvac
BillyHvac
Journeyman HVAC Tech
22,894 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