American Standard Problem (SE)

Glenn Harrison

Now i'm not going to claim to be an A.S. expert, but I have worked on a number of Carrier variable speed units, so maybe this will help. All the units I have ever worked on light in high fire mode and then ramp down to low fire. If this is how the A.S. units work, then your gas pressure should be higher on startup. If they light on low fire, then this won't help.

Was this unit factory converted/set up for propane or field converted? If factory set up, check all the orifaces, burners, and valve to make sure it has all propane components. If field converted, maybe you should get another conversion kit, as there may have been a defect with one of the components in the first kit.

My last suggestion, replace the ignitor. Maybe it's not getting hot enough all the time. If this dosen't work, replace the burner orifaces and burners and be sure to specify PROPANE use. Maybe someone put the wrong burners in the unit.

A whole lot of maybe's, but hopefully one of them will get you running.

Glenn Harrison Residential Service Tech

Althoff Industries Inc. Mechanical and Electrical Contractors

Crystal Lake, Illinois

Steve Ebels

Random Lockouts

I have a new (3 weeks old) American Standard AUY080 that has me stumped. As far as I can tell, the distributor and the factory are also because I haven't had any concrete answers from them. This is a two stage variable speed that is direct vented. The problem is that with the ignitor up to temp and gas flowing it will intermittently fail to light off during the ignition cycle. The low stage is supposed to be set at 3.5 to 4.5 WC". (LP gas) I now have it set at 6 on low and it will still fail to light. At 3.5 it would miss about 50% of the time. Incoming gas pressure is set at 11.5 and does not drop when gas valve opens. The intake and exhaust piping goes straight up from the furnace for 3.5 ft, each make a 90 and run 9 feet over to the wall and out.

This unit will light fine most of the time at the 6 WC" where it is set. Temp rise is right at the verge of being too high though and that makes me nervous. (We all know how air filters are maintained). About every other day the HO has to go down and reset the furnace even with the 1st stage set at 6 WC". Both He and I have sat and observed the whole ignition cycle and watched the manometer go to 6" while nothing happens. I have never seen anything like this.

Any thoughts or suggestions?

Anyone know a good tech at the factory??

I wish I could just do boilers. I've never had a Buderus or a Viessmann cause me any stress whatsoever.

Boilerpro

Still working on my 3 WM HE's with same problem

I'll let you know what I find out if you tell me what you find out. Haven't got any concrete answers yet, but WM tech is working on it.

Boilerpro

Unknown

Wish I was close to you guys

I would love to get a look at these problems. Steve give me some control numbers and I will see if I can come up with something. The thing that comes to mind with all these problems with LP gas is the gas itself and the relation to temperature and the gas being fully vaporized. The flammability limit can be affected by changes in specific gravity and btu content of the gas. If your pressures are set correctly I would try adjusting the primary air mix at the burner opening.

Another thing to try is to disconnect the incoming outdoor air and see if it will work okay with it disconnected. I have had this happen several times. We then increased the size of intake air vent( 2" to 3") and the problem went away.

Steve Ebels

Hey Timmie

Here's wishing you and yours a very Happy New Year!

As for the primary air adjustment....... there is none on these types of burners. Inshot is the term. It's just a stamped metal venturi tube with a wing to carry over to the next burner. There is no ring or shutter to adjust. A classic case of the manufacturer taking the technician out of the equation. Dumbing it down so to speak. I'll try the vent thing. It just seems to me that it has to be a mixing/proportioning problem.

Thanks

Sherwin Swords

auy080 Am. Std.

Go back, set all gas pressures according to manufacturers specificatons. Set high side first, then low pressure. Be sure to go exactly by manufacturers directions. If still problems, pull burners assy. Inspect burner cross over slots, (where flames is spread from one burner to next one) even if they look good and clean, clean them with small knife blade, or other metal that you can slide down into the slots. If you still have problems with it lightning correctly, adjust your igniter just slightly, more into the gas stream. I have two of these in my home, (one auy080, one auy060) and have installed several for our customers in last year or two. have only had the above problem you described with one. (auy100) Good luck. If you can't solve the problem, e-mail me direct. Be glad to help.

Floyd

Check press. switch....

Have had these thungs cutout like you said and come to find that it was a press. switch problem....
You just said it doesn't light......does it actually light and then quit right of way????
Sometimes if the press. switch is hanging on the edge the extra little poof from lighting will cause it
to cut out. Also check that the vent pipe hasn't dropped and trapped water anywhere..... had one earlier this
fall that the HO had screwed with the vent pipe over the summer.....

Just some more ideas...

Floyd

Steve Ebels

Thanks to everyone

Here's a few more details. The A.S. furnaces light on low fire according to what I've been told. Low fire gas pressure for LP is supposed to be 3.5 to 4.5 WC" which is where this unit will fail 50% of the time. The furnace has the new ignitor. It was a late November production run so it's as up to date as you can get. The orifices have been checked and double checked for correct size.

Occasionally I will see the flame start and roll out for just a second or two literally. When that happens it will usually stay lit but it does pop when that happens. It seems to have a very short delayed light off also when this occurs.

Thanks again I'll keep on looking and thinking. In the meantime keep the suggestions coming. This is already more help than the factory tech has been.

Earthfire

backdraft?

Try checking the draft at startup . there maybe a wind induced intermitent backdraft (backpressure) that is causing ignition failure. are there bushes or trees or structures near the vent termination that can affect the draft?

Steve Ebels

Guess what........

I called the customer this morning about 7:30 and told him to wiggle the intake pipe out of the socket in the furnace and just let it sit alongside the 2" opening. It fired without a hitch all day. Just called him back about 10 minutes ago. He's happy. I'm puzzled. There is no restriction or blockage in the pipe and it's well below the maximum allowable for number of elbows and length. Like only 25% of max. So what gives here. Some freaky vortex or swirl caused by just the right/wrong set of piping circumstances?

It's running but I'm still stumped as to why.

At least I can sleep knowing they have heat tonight.

Unknown

Steve

the fact that it will fire okay with the intake disconnected says something is wrong with the intake.

The other thing is possibly the increase in air coming in and the difference in temperature could affect it.

The other thing is a possible pressure switch that is right on the edge, now that you have changed the air it may be able to work a little better. In reality you may have changed the pressure differential.

I have left intakes to draw air from sources other than outside, crawl space, attics etc.

Glenn Harrison

My first question now is will it stay lit if you go back and lower the gas pressure down to the 3.5" to 4.5".

You did say that this is a variable speed unit, correct? Now I'm thinking the variable speed inducer motor isn't running at the proper speed. Too fast or too slow. If this is the case, good luck trying to figure out wether it's the motor or the control board. Get the trouble shooting book and test the motor and control board. If the A.S. units are like the Carrier's, there should be a section to tell you how to test the R.P.M. of the inducer motor based on a D.C. voltage output to the board.

Glenn Harrison Residential Service Tech

Althoff Industries Inc. Mechanical and Electrical Contractors

Crystal Lake, Illinois

Floyd

Had a Walmart bag....

stuck in the intake pipe once.... still got air through it, but had nuisance cutouts like that.....
finally cut the pipe apart and found it hung up in there......


You sure there is no place for water?????


How far apart are the exhaust and intake pipes???? Is there any chance of recirculation of exhaust gases???


Just some thoughts....


Floyd

Steve Ebels

My thoughts exactly Glenn

If I have time today I'll go back and reset the gas pressure and see what happens. I have a service manual that gets into checking inducer amp draw but it doesn't get into the why and which part type of troubleshooting.

Good thoughts

Thanks

Steve Ebels

Thanks Floyd

I've found some wierd stuff in intake/exhaust piping too. Just this fall I dug a nest of swallows (very crispy) out of the exhaust side of a concentric vent on a Carrier. They had nested in there during the summer and had gotten into the pipe where it ran vertical for a 3' distance. It was too slippery for them to get back out and all 4 of the young-un's were wadded up by an elbow.

There is no place for water to collect. Straight up 4 ft and straight out 8 ft for both intake and exhaust. The vents terminate about 6 feet from an inside corner on the south wall of the house. The intake elbows up, rises 1 ft and ends with a 180* bend pointed down. The exhaust elbows up, rises 2 ft and elbows straight out away from the house. Have done hundreds of them in this fashion and not had any problems. The pipe and fittings are 2" PVC which is well within the venting specs in the installation book that comes with the furnace. The pipes are 12" apart horizontally and the terminations are approx 15" apart vertically.

Jim B

American Standard Problem (SE)

Being an A/S dealer and only installing 2 propane units, I feel a little out of place here. BUT I have installed quit a few of the "AUY" furnaces.
My first question....what is the code that the board blinks out. I did not see this info anywhere.
Second....(not question)...maybe it should be 3" venting.
The (2) AUY's (gas fired)inparticular that I remember (only because it has been in the last 8 weeks) AUY's with immediate problems with starting up and running. I replaced the board and have had no problems
Just my $.02 worth

Steve Ebels

The failure code light

Indicates "exceeded number of tries" . It goes through all the steps including opening the gas valve but fails to light up. The installation manual shows that this installation is way under 3" venting lengthwise.

Jim B

codes

Now there is one for me..........I have the Integrated furnace control error flash codes in front of me and see no "exceeded number of tries" . I have an AUY80 in my house and as far as the venting.......there are some "gray" areas where we use 3" venting on 80's. I didn't take time to read all replies, but I thought one said you removed the vent pipe and the unit runs.

Unknown

Vent sizing

it has been my experince on many of these jobs that the information on intake and exhaust PVC sizes was in error. I have resized quite a few jobs to 2 1/2" or 3" in order to overcome intake and exhaust friction. None of them have ever come back. I would reset all pressures and settings according to manufacturers specs. Run the job for a few days with intake disconnected(as long as air supply is good and not contaminated). If that works then run new intake of 2 1/2" or 3". I have had factory reps tell me that could not be what is wrong, they were wrong cause it worked. This is what makes direct venting and side wall venting tricky. I have had some real weird stuff over the years that no one could expalin then you are on your own to start trying things until it works. When it is not electrical or mechanical failure then it is tricky to pin down.

Just another point some equipment will allow you to use inside air for intake and then just exhaust flue gases, that might be another option if specs will allow you to do that. There is equipment that allows that to be done. Check it out.

Herb

intermitent lockout

You mentioned that the intake and output pipes are snorkeled up. I've found that bees love to build nests in the sheltered (intake) pipe. You may have a small one rolling around in there triping the diferential switch. Last one I saw, the homeowner had put screen over the optional indoor air hole to keep the bees from getting into his basement! The other odd thing about that install was the condensate would drop from the outside air pipe onto the wiring harness dropping the flame sensor amps low enough to cause the board to go into its flame sense failure code. Good luck Herb

Steve Ebels

No bees

This furnace was just installed about 10 days ago. The bees have been tucked in for winter long before that. I did dig a hornet nest right out of a burner box a couple weeks ago on a different furnace. Two pipe, sealed combustion. Had a nest about 4" in diameter hung right behind the ignitor and it finally caught fire. The HO called because the "furnace smells really wierd".

Steve Ebels

Hey BoilerPro

Have you solved your lockout problem yet??

wendy whitcomb

furnace smell problems?

i want to thank everyone who encouraged me to not give up!i finally found a company who doesnt have their head up their asses!so, far theyve found 4 gas leaks in the hot water tank piping(was finger tight)the gas line was actually run through the heater ducts-with a pucture hole a and slice in it.drawing gas and manoxide through out the whole duct system.i am happy to tell you ive now installed a electric tank. my furnace is also giving of high readings of manoxide so im in the process of getting that fixed,it sounds like none of the pipes are gluded together.im so glad that i didnt give up,we are very lucky to be alive.my advice to everyone is dont give up if you suspect something is wrong because there probally is.

jim lockard

Auy

I would like to put a mag gauge across the inducter draft motor and the pressure switches both with the fresh air pipe on and with it off. I would like to check the drain connections. I have had your problem before and fixed it, I can not recall how only that it was minor, and involved red caulk. Best Wishes J.Lockard

S Ebels

Jim

This is an old post (2003) and I don't know where it came from or how it got back up here but for the benefit of all I'll explain the problem and what solved it.

The basic problem was that the ignitor was positioned in such a way from the factory that an area with less than peak temperature was exposed to the incoming gas from the burner. The ignitor would warm up (new nitride type ignitor) gas valve would open and nothing happened, After a try or two it would usually light up but occasionally it would fail enough times to lock out.

I solved it by relocating the ignitor so that the hottest area on it, the middle to the tip, was the area "seeing" the flame. The factory location had the lower 1/3 of the ignitor in the incoming gas stream. This was after trying two other ignitors, checking venting, testing draft and inducer differential, gas pressure, etc, etc, etc, many calls to the distrib and the factory........

This was on LP gas and was a new install that nearly drove me nuts. The factory and the distributor were of no help whatsoever and I was paid $00.00 for 5, 60 mile round trips to the customers house. They never offered to pay for my time and when I asked they told me that they would consider my claim for labor and mileage but I never heard a single peep out of them. IIRC, I sent them a bill for about $560.00. I even called down to Tyler to let their tech service dept know about the issue and what I did to resolve it, so they could pass it along to other techs who encountered the problem. Their main concern seemed to be that I modified the furnace from factory spec, not the fact that their design didn't work. I ran into this on 4 other AM furnaces, all on LP gas.

Needless to say I don't do a lot of business with them anymore.

jim lockard

Thanks Steve

I like A/S products but have had simlar problems with A/S distributor not stepping up to the plate when a problem arose. Some years ago I had a mispiped heat pump and time after time the distributor said he would meet me on the job site, I would wait the customer would wait and no one ever showed up. When they final did show and I explained that the machine was mispiped and showed them, they agreed sent down a new machine and promised labor money -still waiting for labor money. Best Wishes J.Lockard

Glen

gas valve

needs to be tossed. I have had two like that this winter - same problem. Great furnace though - if you have to put in scorched air -