RE: American Standard ignition problems (S Ebels)

Glen

I too like a number of things this company is doing with forced air - and backing it up with technician training and support. I am told that the sessions in Tyler are worth going to - and if any of the local sessions are an indication - worth every penny. We had two fellows from Tyler that kept us in stitches for two days - and I still refer to my notes constantly.

Steve Ebels

I posted a while back regarding a failure to light on an A/S variable speed furnace. This would apply to Trane also. The unit we are/were having problems with is very new production (December 02)2 stage variable speed. The problem as you may recall was that it would complete the ignition circuit, power up the ignitor and open the gas valve but fail to fire. We had tried different gas pressures from nominal setting of 4" w.c. to 7" w.c. (LP gas, first stage). Also different venting scenarios of all kinds. Long story short it looks like it has to do with ignitor position. On the unit in question the ignitor is placed quite high in relation to the inshot burner and the carryover wing to the next burner. By having it placed so high it exposes a cooler portion of the ignitor at the gas entry point. The ignitor is hottest in the middle but the gas is actually hitting the lower 1/4 to 3/8" of the ignitor. I field engineered (bent and hammered) the bracket to position the hot midsection right in front of, and as close as possible to the wing. We haven't had a failure to light off since. In fact, while testing my masterpiece of bent metal , I ran the gas pressure from normal all the way down to 2" w.c. and it still lit off flawlessly without fail.

Just for everyone's info and use in the future. You may run across one of these or the same symptom on another piece of equipment.

Glenn Harrison

Thanks for the update, Steve!

Is there going to be a service bulletin listing this as an official problem and a Trane-A/S approved repair eventually?

Glenn Harrison Residential Service Tech

Althoff Industries Inc. Mechanical and Electrical Contractors

Crystal Lake, Illinois

Steve Ebels

I haven't heard

I know for a fact that A/S has engineers out in the field looking at this problem. I spoke with one of the guys in tech service down in Tyler TX. They are fully aware of it and somewhat baffled as to why but they don't deny it's occuring. I was told they had reports of only 8-10 units that exhibited this failure. (Naturally, I got one) The bracket will likely be redesigned. Possibly some changes made in the ignitor logic part of the control board. The bracket was one of the things that was changed in the latest production models supposedly to improve light-off. What's the old saying........."If it ain't broke don't fix it" ???

A/S has been really good about it and has offered my customer a free 5 year parts and labor warranty for all their trouble. They have had no heat on 8 separate occasions since we installed the unit. That really stings me. We take a great deal of pride in our work and the equipment we sell and this type of thing drives me crazy. That's 8 50 mile round trip excursions for me plus about 14 hours of labor playing with the unit trying to figure out what the heck was going on. Kinda sucks all the profit out of that job plus a couple more. No word on reimbursment for me yet. Hopefully they will give us some kind of allowance for all the time and trouble.

Unknown

Sometimes I feel like

a design engineer. After having spent many hours redesigning a factory defect and much labor hours (with no pay) the factory tells me of yeh we know all about that here is what you should do. Then you do it and it still does not work.

Days and hours later you really figure out what to do and the results are good and it works. The factory then comes out with a whole new design based on your findings. They never even say thank you. Been there, done that and have T-shirts, ball caps etc but no recognition.

Must say in all fairness some are better than others. At least the Honeywell rep buys lunch. I can tease him as we are good friends.

Glen

compensation

I just went through the latest info from AmStd - no word at all on this problem. Is this on the 80 or 92+ % furnaces? And - if AmStd has offered the HO some sort of peace offering - it has been my experience that if you send them a reasonable invoice for T&M - it gets paid. Especially when this have been so well documented and in no way has been caused by the install procedures!

Steve Ebels

Glenn

This is on an AUY080 two stage variable speed furnace. The problem is apparently limited to December 2002 production so very few of these are in the field as yet. They likely won't have a service bulliten on this for a few weeks until they have had a chance to test and duplicate what we did in the field.

I really do like this piece of equipment despite all of this. I appreciate the fact that they are trying to build longevity into all the components. The ignitor especially. It's made of tungsten and covered with silicone nitride. The furnace control board has adaptive logic that will "learn" how much and how long it needs to apply voltage to the ignitor in order to affect a reliable light off. This increases ignitor life dramatically. The draft inducer runs only as fast as it needs to keep the pressure switch closed and retests itself every 250 or so cycles.

You know.......someday they may even succeed in building a furnace as reliable as a boiler. Some day........... maybe