I've got a 5 burner Trane (7 years old) where the stage 1 heating fails and the stage 2 heating works fine. If stage 2 comes on first and drops to stage 1, then stage 1 works fine (all 5 burners remain lit).
In the stage 1 failure mode, the ignitor lites (near burner 1) but only the first two burners ignite. The ignition sensor appears located at burner 5 and after a few seconds the gas shuts down. It then recycles in this mode until it seems to lock up permanently. A power on reset will cause it to go back in to recycling failure mode.
The installation manual, describes adjusting the stage 1 to 1.4 - 1.7 W.C using a "manifold pressure guage". Stage 2 is 3 to 3.5
My thoughts are, unlikely igntitor problem, possible regulator problem or aging regulator drift for low pressure.
My first reaction is to go in and check and adjust the Regulator low pressure to spec - but why has it become "too low"?
Considering this is probably a 1 time adjustment, what kind of meter can I buy and how do I use it? I see digital manometers ranging from actual $19 water filled to digital $245.
Also I dont know if the burners are supposed to lite sequentially from burner 1 to 5?
any thoughhts on this?
Trane verbally says to adjust 1st stage to 2.0 even-though the manual says 1.7. Also is this gas valve a newly replaced one or original one? If it is the orginal one verify two things one the inlet pressure is enough and two the inlet screen is clean. If it is a newly replacement valve and is the new W/R new style Valve replace it again until you geta good one.
Its Original. How do I verify inlet pressure? the manual talks about clocking the gas meter - good enought? And does stage 2 working imply adequate inlet pressure?
For future reference are you saying the new W/R valves are better or cheaper?
I'll check the sceen right now.
Crossovers clean? I followed a tech on a Choo Choo, crossovers were rusty and often only the burner by the ignitor lit.
Crossovers? If those are the tubes that go between the orifice and what I assume is the heat exchanger they appear good. the disks on the exchanger side have a "rust like" color but all the holes are clear and it shed rust when rubbed.
I visually inspected the inlet screen and it appears clear.
So at this point I have two quesions.
1) With what equipment to I measure the inlet and outlet pressure at the labeled taps on the W/R regulator?
2) Whats a good way to clean the crossover disk holes?
It now works. Why? Cant tell for sure since I "fixed" mulitple things.
In cleaing the crossovers I noticed the first crossover beyond those next to the ingnitor, had a disk that was not properly seated all the way by a tiny amount. I moved it to the last position.
But I also confess to using tape at the adaptor to the regulator instead of compound. It is just possible that some excess tape was slightly blocking the inlet. I was real careful in taping this time.
Could be a combo, or just cleaning the crossovers, but thanks again for the tips