# Trane XR95 Problems



## bob22 (May 28, 2008)

If gas unit, see if flame sensing rod is dirty; clean it up with some emery cloth.


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## diyorpay (Sep 21, 2010)

Check videos in older thread:

http://www.diychatroom.com/f17/furnace-problem-96887/


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## cipherman (Sep 16, 2011)

Thanks for the feedback so far. This is a new install. Long story but I am in the middle of getting a new HVAC contractor. In the meantime, I am looking to diagnose myself. 

I did some additional troubleshooting. I opened the burner cover during heat call and observed that the ignitor is indeed glowing in sync with the relay flipping back and forth. So it appears that the ignitor is trying to light the gas but the gas never gets lit. I checked that the gas in indeed on at both the main pipe coming into the furnace as well as the gas on/off switch inside the furnace.

Since the gas never actually ignites the flame sense isn't the problem since it is actually doing its job. What would cause the gas to not ignite even though the ignitor is glowing red hot??


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## hvactech126 (Nov 11, 2010)

do you hear the gas valve open? Have you checked for a diagnostic code on the control board? Check for 24V between the gas valve wires during the ignitor operation.


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## cipherman (Sep 16, 2011)

Unfortunately this model of Trane provides very little in the terms of error codes. Basically it is just blinking slowly which indicates a call for heat. 

For awhile I noticed the ignitor glowing but now it doesn't even seem to be glowing at all. I am suspecting a gas flow problem as the root cause which might have now also ruined the ignitor. I verified that I have 120V on the igntor leads but the ignitor is now not glowing
with the voltage. I am going to check on the gas valves a bit closer as well.


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## hvactech126 (Nov 11, 2010)

no, they show error codes as they should or there is a problem with the control board. I'm a trane dealer. Let it run through it's cycles and it will produce a fault code.


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## cipherman (Sep 16, 2011)

Great thanks. You are correct. I let it sit a bit in the faulted state and it is kicking out 3 flashes which according to the 
Installers Guide indicates a "Pressure Switch Error"

What should I check based on this info?

Thanks


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## hvactech126 (Nov 11, 2010)

check the flue pipes to make sure they are clear. lift the pipe in the middle (intake) up and make sure their is no debris in it. Often birds try to nest in the flue pipes. the inducer motor could be weak, or full of condensation causing it to not flow properly. The proper way to determine if it is the switch or a blocked flue is using a manometer.


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## New user XR95 (Dec 5, 2014)

*XR95 installation problems with 3 blinks of led*

Trane stated that the unit has a 2" vent outlet but the piping should be 3". My contractor installed 2" with three 90 elbows and the inducer would come on but no gas would flow and the igniter would not light. Replacing the 2" with 3" and only using two 45 elbows fixed the problem. Even though it seemed to be a lot of flow from the 2" piping it prevented the pressure switch from closing allowing fuel to flow and igniter to light it. Hope this helps. You would think they would put this in the manual. If you are a Christian read John 14:16, we are born with the Holy Spirit in our hearts, believe it. God bless
new VR95 user


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## hvactech126 (Nov 11, 2010)

It is in the manual. Venting lengths are always put in the manual. I'm not sure what your post has to do with a 3 year old thread....


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## pdbrental (11 mo ago)

Saw your post back in 2011 on the trane. I need to replace the igniter, can you help me with that?
I am trying to open the cover of the frame pipe, after I remove the twice screw, it is still very tight, how do I open it?



cipherman said:


> I am having problems with Heat on a Trane XR95 system. I verified that all wiring from the thermostat to the unit is correct and the unit is seeing a call for heat. I confirmed this with a meter on the W lead (24V) as well as the unit flashes 3 times with the RED LED which according to the manual indicates a call for heat.
> 
> The problem is that the blower starts but the burner never fires. I have attached a picture of my control board. The relay that I circled continuous switches on and off about once a second. It appears that the unit is trying to start something else which is failing. Does anyone have an idea what the relay controls?
> 
> I really appreciate any assistance.


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## Olde Eddie (11 h ago)

Found an interesting solution to this issue. Had the 2 red flash error code, replaced all pressure switch components with no solution. Then noticed only one burner (out of 4) was igniting before the whole thing shut down. With only the 1 gas line feeding them, thought maybe not enough gas getting through the valve. Replaced the gas valve and everything works as advertised. Oh well, shouldn't have a problem with the pressure switch components for quite a while.....


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## roughneck (Nov 28, 2014)

Olde Eddie said:


> Found an interesting solution to this issue. Had the 2 red flash error code, replaced all pressure switch components with no solution. Then noticed only one burner (out of 4) was igniting before the whole thing shut down. With only the 1 gas line feeding them, thought maybe not enough gas getting through the valve. Replaced the gas valve and everything works as advertised. Oh well, shouldn't have a problem with the pressure switch components for quite a while.....


Gas valve will not cause a pressure switch to open. 
If you replace the gas valve the gas pressure must be set using a manometer, the same way you troubleshoot a gas valve in the first place.


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## Olde Eddie (11 h ago)

Understand. For some reason the pressure switch error code was showing up, even though it's not related. But when only one burner kicked on, at the opposite end of the flame sensor, decided to replace it and see. Weird how some things work.


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## roughneck (Nov 28, 2014)

Olde Eddie said:


> Understand. For some reason the pressure switch error code was showing up, even though it's not related. But when only one burner kicked on, at the opposite end of the flame sensor, decided to replace it and see. Weird how some things work.


What was the manifold gas pressure with the old valve, and what pressure did you set the new valve to?


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## Olde Eddie (11 h ago)

Hey Roughneck. Didn't check or adjust anything, used the factory settings whatever they were set to. Old one has been working fine for 9 years and suddenly didn't anymore. Got the pressure switch error codes so changed those parts. Then noticed only one burner lighting, not the one near the flame sensor, before the unit shutdown. Thought valve was not opening enough so replaced it. All working great now.


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## roughneck (Nov 28, 2014)

Olde Eddie said:


> Hey Roughneck. Didn't check or adjust anything, used the factory settings whatever they were set to. Old one has been working fine for 9 years and suddenly didn't anymore. Got the pressure switch error codes so changed those parts. Then noticed only one burner lighting, not the one near the flame sensor, before the unit shutdown. Thought valve was not opening enough so replaced it. All working great now.


Setting the pressure on the new valve is mandatory. You’ll need to do that. It’s not pre-set.
Doesn't sound like the old valve was faulty. Sounds like dirty burners.
A manometer is mandatory for diagnosing a faulty gas valve.


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## user_12345a (Nov 23, 2014)

They are supposed to ship from factory pre-calibrated for 3.5" but may be off - hence the need to check.
Plus not all applications necessarily need 3.5", manufacturer's instructions must be followed.


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## roughneck (Nov 28, 2014)

user_12345a said:


> They are supposed to ship from factory pre-calibrated for 3.5" but may be off - hence the need to check.
> Plus not all applications necessarily need 3.5", manufacturer's instructions must be followed.


Output directly depends on input pressure (which should also be checked), and that is a huge inconsistent factor. 
Don’t think Ive ever pulled a valve out of the box that was set right, I’ve had to adjust all of them. 
Some areas have a dip in gas pressure during the winter, have to adjust output with that figured in.


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## user_12345a (Nov 23, 2014)

roughneck said:


> Output directly depends on input pressure (which should also be checked), and that is a huge inconsistent factor.
> Don’t think Ive ever pulled a valve out of the box that was set right, I’ve had to adjust all of them.
> Some areas have a dip in gas pressure during the winter, have to adjust output with that figured in.


Isn't the point of the regulator to maintain stable output as inlet fluctuates?
Though may not be perfect, and the valve could be thrown off if bumped or vibrated when transported and installed.
Agree it must be checked.


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## roughneck (Nov 28, 2014)

user_12345a said:


> Isn't the point of the regulator to maintain stable output as inlet fluctuates?
> Though may not be perfect, and the valve could be thrown off if bumped or vibrated when transported and installed.
> Agree it must be checked.


It keeps it somewhat stable. But only to a point.


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