A.O. Smith

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Stay Away From A.O. Smith Promax Gas Water Heaters
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MILWAUKEE, WISCONSIN -- After my previous water heater failed after 31 years, I had a 30-gallon A. O. Smith Promax gas water heater installed on October 30, 2007. On November 17, after 19 days, the pilot light went out. For the next seven months, the pilot light continued to fail and had to be relit.

The pilot failed sometimes every few days, sometimes every day, sometimes four times a day or more.

Eventually, I had to relight the pilot light every time we needed hot water. The plumber who installed the Promax returned five separate times to try to fix it, without success. An A. O. Smith Authorized Technician tried and also failed to fix it. To help find the problem, I installed a camera at the heater viewing window, and videotaped the pilot failing four times. No one looked at the tapes.

I began to think that this water heater must be pretty bad if an experienced plumber couldn’t fix it after five tries, and an A. O. Smith Authorized Technician, who works on nothing but A. O. Smith products, also could not get it to work.

Over seven months, I had to relight the pilot 63 times. At 10-15 minutes per relight (according to A. O. Smith instructions), this comes to a total of between 10-16 hours I spent lighting this heater. I can assure you that having to lay on your stomach at all hours of the day and night, in a cold and dark cellar, is not a pleasant job for an old man.

A. O. Smith, and the Factory Authorized Service Technician (who is paid by A. O. Smith) blame me for the Promax failure and refuse to refund my money. They say (without any tests or proof) that water vapor coming through the dirt floor in my cellar causes excess humidity which clogs the heater’s flame arrestor, disrupts the air flow to the heater, and puts out the pilot flame.

In 2003, the Government got into the water heater business. It required all water heater manufacturers to fit a ’flame arrestor’ into water heaters. A flame arrestor prevents the burner flame inside the heater from igniting flammable vapors outside of the heater. All heater manufacturers were allowed to come up with their own design of flame arrestor.

I learned from some plumbing websites that the real problem with the Promax may not be my cellar, but the design of its flame arrestor. All incoming air for the heater’s operation must pass through the flame arrestor. The Promax uses a flame arrestor made from a Corderite ceramic disc. This ceramic disc is about the size of a saucer, so limits the air coming into the heater. In addition, the openings in the disc itself are small, further restricting air flow.

Aside from any design problem with the Promax, there are several reasons why A. O. Smith blaming me for the Promax failure is nonsense.

I was given no warning before purchasing the Promax, either from the plumber or A. O. Smith, that humidity was a limiting factor for the operation of this heater. No one told me that this heater needed a certain humidity range in order to work, much less what the humidity range was supposed to be. If I had known beforehand of a potential problem, I would not have bought the Promax heater.

The excess humidity conclusion is not supported by statements in A. O. Smith’s own Instruction Manual (#184165-003) and Service Handbook (#TC-049RC). In these manuals, the word ‘humid’ is mentioned only once in 93 pages, and then only as an indication of tank leakage, not as a cause of pilot flame failure. These manuals are available on A. O. Smith’s website http://www.hotwater.com/lit.html.

Saying that my cellar is too humid, does not make it so. During December 2008-January 2009, I tested the relative humidity in my cellar using a Honeywell hygrometer. For these two months, the relative humidity was in a range from 51%-65%, staying mostly in the mid-50s.

A 30%-65% range for occupied areas is recommended by The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE thermal comfort standard for Human Occupancy, Standard 62.1-2004). Their chart can be seen at http://www.ccohs.ca/oshanswers/phys_agents/thermal_comfort.html.

This means that even though my family doesn’t actually ‘occupy’ our cellar, the relative humidity there is within ASHRAE standards. This normal reading is more significant in that during January 2009 we had four times as much snow (i.e. more moisture thus more humidity) than during the same period in 2008 when the Promax was installed. In other words, during January 2008, the humidity level in my cellar was probably even lower.

I also tested the wooden beams in my cellar with an Extech moisture meter. All the wood tested normal at 20% or less moisture. My home was built in 1924, so these normal readings are after 85 years of supposedly excess humidity.

These tests show that my cellar is not ‘too humid’ as A. O. Smith maintains and therefore is not likely to be the cause of their product’s failure.

My films of the Promax pilot light failure show that the pilot fails in several ways; it goes out by itself, or when the burner tries to go on, or when the burner is lit and then turns off. A. O. Smith’s lack of air explanation for the pilot failure seems suspect considering that the burner itself, which must require thousands of times the air the pilot does, had no trouble staying lit (once the pilot was lit) during a heating cycle.

The solution for pilot flame outages, A. O. Smith’s Legal Department says, is to clean (vacuum) their ceramic disc flame arrestor top and bottom routinely. To do this the burner must be removed, not a job the average customer can or would want to do.

Some plumbers state (see links below) that it is impossible to properly clean the bottom of this ceramic disc at all, as that part is nearly inaccessible. In any case, calling a plumber ‘routinely’ (every three months? every month?) is expensive and irritating, considering that your old heater may have lasted for decades without any attention at all.



I believe that most people would consider it intolerable if a brand-new car failed to start 63 times in seven months. After experiencing similar inconvenience, not to mention cold water, I replaced the Promax with a Bradford-White heater (my choice and in spite of the plumber‘s objections) on May 24, 2008.

The Bradford-White has a stainless steel flame arrestor, the full diameter of the heater, and lets in plenty of air. The Bradford-White has now been installed for a much longer time than the Promax, and has worked perfectly in the exact same location, in the exact same ‘humid’ conditions.

I am out almost $1,000 for A. O. Smith’s measly 30-gallon gas water heater.

Do yourself a favor and stay away from A. O. Smith.
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User Replies:
madconsumer on 10/28/2008:
I have used ao smith water heaters both commercially and residentially. they are some of the best on the market.

how high is the humidity in the cellar? is the cellar vented at all? do you have good flue drafting?
Starlord on 10/29/2008:
Brilliant! You have trouble with one water heater that may be your fault, and you are telling people to stay away from ANY water heater made by this company. Keep after the installer, they should have enough concern for their business reputation it would be to their advantage to satisfy you. You say the pilot failed on day 19. I would have been bugging the installer on day 20.
haste502 on 10/29/2008:
Kindly read my updated complaint. I in fact bugged the installer on day 19, not day 20. My home is 85 years old, and all the cellar beams, joists, etc. test normal with a moisture meter. All the wood is sound after all these years, not crumbling, flaking, etc. as would be the case if I had such terrible wetness. As I have a dirt floor, the humidity varies based upon the dampness outside. If it rains for three days, my cellar is humid. If it's dry outside, the humidity is less. A. O. Smith is using 'humidity' as a red herring, that is, to divert attention from the real cause of the problem, which is its flame arrestor design. A. O. Smith's ceramic disc lets in little air, and its small openings clog easily. Some plumbing websites (see below) have suggested that A. O. Smith may be facing a class action suit based upon the problems with this heater. Please take my comments for what they're worth. If you have a dirt cellar floor, you may save yourself the trouble and $1,000 expense I had.

anitahotshower on 03/18/2010:
Our story is the nearly the same!! However, we do not have a dirt floor and our water heater is on the main floor in a newly constructed home. We are on our 4th completely replaced unit, and 6th or 7th (lost count) thermocouple, etc...Everything but the tank was replaced 12 weeks ago yet the unit completely failed this week. The AO Smith rep, who only speaks through our plumber and not to us personally, suggests replacing parts again, blah, blah, blah. Of course, we pay labor costs, once more. We cannot afford a new water heater, but, we cannot afford to keep the piece of junk we have. A new Bradford-White is to be installed today. To me, AO Smith's refusal to rectify this problem is warranty fraud. We will be filing a complaint with the Better Business Bureau.
Greg64 on 10/01/2010:
We moved in our house in jan. 2005 and guess what we have an A.O smith promax water heater , 9 weeks after we moved in hotwater heater went out called a tech. to come out and look at it since it was under warranty he could not get it to light so he replaced it with a new one. 6 weeks later it went out pilot would not stay lit. called them again they came out and looked at it and said theres not enough draft going into it even though they lit a piece of paper on fire and held it to the flute draft was flowing great so they drilled five small holes in the floor and added a draft pipe to the attic even though the door to closet has a 1 and a half inch gap at bottom of door, okay they got it lit and left a couple of hours went by and it went out again, they also told me to remove the pilot assembly and vacuum out the bottom, it didn't help I have lit it over and over and over hundreds of times the Tech. even told me they have trouble all the time with the 30 gallon promax water heater. And now it is out again it is under warranty so they are shipping me another pilot assembly so I just want to say A.o smith is getting rich selling these defective hot water heaters. Shouldn't have to replace two hot water heaters in five years. They are come on people have you ever had 2 bad hot water heaters in last five years I don't think so. Lowes Energy saver hot water heaters last 9 to 10 years before they start leaking but the pilot light works great on them they just usually rust and start leaking water I have never had this much trouble with a hot water heater don't believe me buy one you go to get in the shower and you have to light it 8 or 9 times to get hot water but pilot goes right back out.
NMRK1 on 10/26/2010:

Thank you for contacting .... I understand that there are a lot of complaints that are on the Consumer Reports site, but the majority of these complaints deal with maintenance (what kind of maintenance on a new heater?) and change of manufacturing (if manufacturing changes--is that my problem?).

Without having the serial number and model number to your water heater I have no way of knowing what type of water heater you have and that makes it very difficult to assist you on what could be causing yours.

But you do acknowledge that others have had the same issue and you offered possible reasons for the failure of the pilot light to stay lit.

Have your engineers come up with a new design to cure the problem?

Pro Max Plus -- Model FCG 75 300 SN # 1007 AO 1788

What I can tell you is that in 2003 the government made it mandatory to seal up the combustion chambers of gas water heaters, when that happened more maintenance started being required to keep fresh air going into the burner chamber to keep the pilot lit.

The other thing that has changed is furnaces and water heaters used to be vented together, now furnaces are power vented and no longer vented with the water heaters, which means a lot of times the water heater ends up being vented in an unlined chimney or a vent that is too large for the water heater and it causes it to back vent.

My house was built in 1992. The old water heater worked until it had a problem--18 years later a usual life span for a water heater. The furnaces are as old as the house so nothing has changed re venting.

I understand how it is easy to go back to the manufacturer for an inferior product or to automatically assume it is a faulty part, but most of the time it is something outside the water heater causing the issues.

NO, it is not that easy to go back to the manufacturer. Try to find a live human being. I am wasting a hell of a lot of time on a problem that is not my fault. My OLD A. O. Smith water heater is working just fine. Fortunately, it, a much smaller unit, controls the hot water in the other five bathrooms and the kitchen and laundry room. The only reason for the 75 gallon is the swimming pool size Jacuzzi. Frankly I am considering filling the Jacuzzi tub with potting soil and putting in a garden.

I will be happy to assist you with your pilot outages but I will need to have the serial number and model number.

Totally ecstatic. I am only 73 years old. I continue to be the first one to have a problem with...... No, I am not.
James W. on 08/03/2011:
Built our house in 2004 and had an A O Smith hot water tank installed. It is a 75 gallon natural gas vented tank. After only 6 months of usage the tank is leaking all over the floor. Call the A O Smith representative who advised the tank was good for only 6 years not 6 1/2 years. We paid $ 1200.00 to $ 1300.00 for the tank only to last 6 1/2 years. That is ridiculous ! My last tank lasted 13 years before we decided to upgrade to a bigger tank and cost several dollars less. Called the corporate office and explained the situation and they advised someone will call me back. I am a Fraternal Order of Police member and will be submitting a motion to have all the other lodges in the state of KY to boycott all of A O Smiths products....then maybe someone will take the time to address the problem.
sickofit on 04/27/2012:
I have the same problem, my house was rebuilt after a house fire in 2005. I have a vacuum attachment that I can get to the bottom of the disc with. It usually gives me between a week or a month before it quits again. Very frustrating.
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Will not own another A.O. Smith Water Heater
Posted by on
AKRON, OHIO -- This is what to expect of customer service for any warranty claim through A. O.Smith.

It all started when the pilot kept going out on just now a 2 year old water heater after each cycle.

I sent AOSmith an email stating this (4\3\09):

I purchased this heater (2) years ago to date. Since last week or so the pilot has to be reignited after every cycle. I'm thinking along the line of a thermocouple problem. Warranty should cover this correct?

No response from that after two days I sent this(4\5\09):

I submitted a question days ago, still have not received an answer. Your Customer Service is sub-par. The equipment alike. (2) years old and I have to replace parts. Will not use or refer your products in the future.

Still nothing, so I sent this(4\6\09):

4 days and still no response. You're right on top of things here. Good CS\PR you have.....which excuse will it be, First rodeo? Really busy? Family emergency? All techs are assisting others? Computers were down? Bad weather in Tibet?

Big "hurry" to take our money when purchasing your products, but thanks for "nothing" when somethings wrong with them?)

Finally, I get a response, or at least I thought it was. Typical reply from them asking for all the info that I'd already given them while registering onto their website(4\6\09):

We sincerely apologize for the delayed response to your email. We would like to ask a few questions for troubleshooting purposes. Recently you requested personal assistance from our on-line support center. Below is a summary of your request and our response.

We will assume your issue has been resolved if we do not hear from you within 96 hours.

Thank you for allowing us to be of service to you.<----"That's a joke!"

Pilot outages can be due to a variety of things.
We would like to help you with determining what the root cause might be, and will need the answers to some very important questions to do so:
1) When was your water heater installed?
2) When did you begin experiencing pilot outages?
3) How often is the pilot going out?
4) Does the pilot go out in conjunction with anything else in the home turning on or off or anything else that you can think of (temperature outside, winds outside, doors opening and closing)?
5) Where is the water heater installed in the home (basement, attic, closet, utility room, etc)?
6) What is the size of the room where the water heater is installed?
7) How is fresh air supplied to the water heater?
8) How is the unit vented (from water heater to outside termination, include number of elbows and degree - 45, 90, etc.)? What size vent pipe is used? What is the length of the vent?
9) What is the altitude where the water heater is installed?
10) Are you using natural gas or propane (LP)?
11) What is the system gas pressure, static and in use? And, what is the manifold gas pressure, static and in use?
*A plumber with a digital manometer will be able to check the gas pressure readings.
12) If this is a flammable vapor ignition resistant model (FVIR/C3), is the LDO screen (Lint, Dust, and Oil screen) clean and properly in place? (If the LDO screen was not in place or if it is dirty, there could also be debris within the water heater clogging the corderite disk and blocking air flow).
*The LDO screen is located on the front of the water heater, beneath the burner chamber. It is a black screen, similar to what you find on your household dryer.
13) How many people are using this water heater?
14) If you have a digital camera, it would be helpful if you could send pictures of the installation from water heater to termination outside. If you can do this, we will need them in. jpg or. jpeg format.

Thank you,

I replied(4\6\09):

(I waited 80+ hrs for you to only be given 96 hrs to reply back to a 14 part questionnaire with requests of pictures and a manometer? What is this BS? Already gave date of installation, problems that are happening, serial & model #'s, name, info, first born...etc etc I've answered enough of your questions now please answer mine? I have receipt of purchase of the water-heater (2) years ago to date of the second of three submissions (4\3\07)I've sent to you. I've already had a licensed H\AC contractor here and diagnosed that the thermocouple is bad. Question is: Is replacement of the thermocouple for a just now (2) year old AOSmith 40gT Pro Max Gas Water Heater under warranty?)

They replied(4\7\09):

(We apologize first of all that you had to wait for a response. I was out of the office due to a family emergency.) <----"Hmm, What did I tell you?"

(The thermocouple on this unit cannot be replaced as an independent part. The entire pilot assembly would need to be replaced. If your plumber feels this is the problem with the unit then he may go through the local distributor for the part in warranty however, if the problem continues we will not be able to assist you further without troubleshooting.

Thank you,

I replied(4\7\09):

(Troubleshooting has already been assessed and diagnosed the thermocouple\assembly is bad? What will I need to pick up this [Quote:\]for the part in warranty[UnQuote:\]? I purchased and picked up the heater from the distributor, it will be myself (not the plumber) going to get the part.)

They replied(4\7\09):

(You would need to contact the distributor where you purchased the unit to determine what they will require from you for the part in warranty.

Thank you,

I replied(4\7\09):

(This is the whole reason I've contacted you or (A. O.Smith). The distributor where I purchased the heater from is no longer practical to which is why I followed instructions (As listed under "claim procedure"). The part in warranty that you referenced (thermocouple assembly) for the Pro Max GCV 6yr tank\6yr parts Ser#M06AO27556 Mod#GCV 40 100. All required warranty applications are in accordance as specified under terms and conditions. (See attachments) [Quote:\] A. O.Smith Water Heaters (the warrantor) will furnish the ORIGINAL OWNER, 1) a replacement A. O.Smith water heater of equivalent size and current model if the glass-lined tank in this water heater leaks and, 2) a replacement part for any component part which fails.[UnQuote:\] Photo's show proof of purchase per residential installation, residential gas warranty and rating plate.
I've purchased this heater to "heat" my water, it's not doing so. I've logged onto your website and sent the claim of the thermocouple assembly not working properly almost a week ago. Six days later you've referred me back to the original distributor along with apology including an unfortunate family emergency? All the while I'm still without hot-water. Please, just supply the name of a local (A. O.Smith) distributor that has the part in stock, address, phone # and a claim reference # to pick it up. Regards,)

They replied(4\8\09):

The closest distributors in your area are Wolff Brothers and Johnstone Supply. A reference number is not necessary for warranty however, I do need to be sure you are aware that our distributors are wholesale only and some will only work with plumbers and contractors.
Thank You, Mary

I replied(4\8\09):

The warranty doesn't say anything about wholesale, or retail distributors. Nor does it say this requires a plumber or contractor is needed to pick up a replacement heater or parts. Says under "Claim Procedure" Any claim under this warranty should be initiated with the dealer who sold the heater, (or with "any" other dealer handling the warrantor's products). Now I went to both Wolff Bros and Johnstone, they won't warrant the part because I don't have acct's there. To which is why I've been talking to you. Since there's already question on your behalf of knowing the difficulty of myself obtaining it through a wholesaler, why did you refer them?

I've received apologies for delays and family emergencies, asked and answered (with photo's) numerous questions for troubleshooting, had a licensed plumber diagnose thermo-couple being bad, referrals to wholesalers that won't help, no hot-water for over two weeks. I believe I've done everything just short of giving up my first born in obtaining this part. These actions alone should warrant a resolution on A. O.Smith's behalf of any further issue with cost of shipping\delivery charges of the part. If you cannot help in furnishing such request, please refer this matter to someone there that can.

They replied(4\9\09):

This is the stores policy and it would have to be followed. Typically, they will charge you up front and reimburse you when the claim is filed. The other option would be to contact our Customer Care Center and the part can be sent out however, you will be charged for the shipping. The rates are:

UPS Ground $10.00
UPS 2nd Day Air $25.00
UPS Next Day Air $50.00

Thank you,

I replied(4\9\09):

I have A. O.Smiths (warrantors) policy and it would have to be followed. This is your product, not the distributors. I've already spent seven days and well over the price for shipping costs with this charade following your referrals. What part of the last few emails that I sent don't you understand that those distributors will "not" warrant the part because they are wholesale only? Meaning, can't even "purchase" the part there to be reimbursed...... "contact our Customer Care Center"? I asked you to do such prior to your last five replies. I feel you have been biased, and done nothing but give sub-par answers, family emergency excuses, and run-arounds. Everything that you've presented has only escalated the problem. Nothing you've stated coincides with the warranty at hand. As stated in my last reply, I no longer wish to deal with you on this matter. Send this email of it's entirety over to whomever "manages" the customer care center to get my part. Not a customer care associate, the manager.

As of (4\8\09) I requested that I be sent to a CCC(Customer Care Center)Mary(A.O.Smith) replied (4\9\09) a run-around and made reference of contacting the CCC, I replied back yet again (4\9\09) to actually have this claim sent to CCC, it's now (4\12\09) and still had no assisstance\service from anyone from A.O.Smith.

Will update as it proceeds.......still in the works here.

As of Monday(4\13\09)Rapidly Replied:


I have sent your request to the supervisor.

Thank you,

Note: Due to a CONFIDENTIALITY NOTICE: Problem Resolved!

I do not (Recommend) by shown e.g. A.O.Smith heaters due to homeowner difficulty in finding\getting warranted parts. This is "my personal experience".

Hope this helped in your decision whether "YAY" or "NAY"?

Thanx for reading my (E-"vent"),


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User Replies:
Soaring Consumer on 04/11/2009:
Very helpful review, this is indeed a bad runaround. I suggest that you file a complaint with the BBB and your state's Department of Consumer Affairs.
madconsumer on 04/11/2009:
this is why I own electric water heaters.
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