Need to replace the burners

Based on the limited information you have given, it may be a bad thermostat.

These have a photoelectric eye , much the same as a motion sensor on an outside lamp, just pull this out, clean with a wet wipe, dry with a towel & replace, press the reset switch & your boiler should fire up producing lovely hot water

http://waterheatertimer.org/How-to-test-water-heater-thermocouple.html

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Clean air intake. Change thermocouple.
American Standard appears to be Bradford White or Rheem product from the one image that appears on the AS site.
Air intake located on side of unit funnels air to arrestor screen located under the combustion burner.
Remove burner and blow out screen with compressed air.
If this is Rheem product, then also inspect for broken glass vial that indicates high-temperature FV event, which might also require other parts to be replaced.
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#pilot
http://waterheatertimer.org/How-to-replace-thermocouple.html
http://waterheatertimer.org/How-to-repair-Rheem-TRD.html

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

I would check the metal door on the bottom near the burner, sometimes they come loose and vibrate. If not that then I would suspect the chimney liner inside the tank, I have seen them corrode and start vibrating when the gas is running

Generally, they are a your normal low end hot water heater. I have seen American Standard units last up to 20 years (like mine) with not problems, and I have seen them not last three years before the tank ruptured.

We have more calls on the Rheem and Brandford Whites than American Standards as far an minor problems.

Pros: Cheap; reasonably reliable; parts readily available.
Cons: Not energy efficient; tank quality - flexible.

When mine goes would I replace it with another American Standard? No, I would install the Bosch tankless water heater.

Hi Kathlene.
Typical American Standard sell sheet for 100 270 AS also shows contact information for company with phone numbers
http://www.waterheating.com/pdf/100270.pdf
One seller shows this product for $3000 + shipping
http://shop.waterheatermaninc.com/product.sc?categoryId=2&productId=10

Rheem builds commercial gas water heaters under their name and under other brand names.
http://www.rheem.com/product.aspx?id=FC6D548B-54EC-46C9-9DC0-79DEC29198D7
Contact Rheem:
http://www.rheem.com/Contact.aspx

For example Rheem GP100-250(A) meets same delivery as American standard product
http://globalimageserver.com/fetchDocument.aspx?id=d26ba16f-c16f-4c45-90a8-d1f5d5f97020
One company sells product for $3900
http://bostonheatingsupply.com/ventmaster.aspx

For example model GD100-250(A) meets same delivery as American standard product
http://globalimageserver.com/fetchDocument.aspx?id=276b892c-1fb8-40f1-8238-51d4a7d84846
This product might sell for $6900

i think since "tankless" water htrs entered the market...your plumber referring to a standard w/h means a storage tank wtr htr(stores 40 or more gals) ..most popular brands are a o smith rheem bradford white

Unable to light pilot Gas supply turned off Turn on gas supply Gas **** knob dial not positioned correctly Check lighting instructions. Set control knob Defective thermocouple Check and replace thermocouple Defective safety magnet assembly Check and replace gas valve Pilot burner orifice clogged Clean or replace Pilot tube pinched or clogged Clean, repair or replace Poor thermocouple connection Check and tighten Air in gas line Purge air from gas line Thermostat's single use ECO is tripped Check ECO and replace gas valve Gas valve defective Check gas valve

I assume you are talking about an electric water heater. The normal life span of an electric water heater is up to 11 years. Before you replace it, try turning off the unit, turning off the water supply, and draining the tank of any built up rust and sediment. Refill the tank, and turn the power back on and see how it performs. If it is still acting up, look at a replacement. On a positive note, the new water heater should pay for itself in pretty short order due to better insulation saving energy (and replacing with a higher efficiency unit may qualify for a tax credit).