GT-199XN2 service repair manual - Rheem Tankless Hot Water Heater Rtg-74pvp-2 7.4 Gpm

1) Call whirlpool
1-877-817-6750
Need model and serial number located on label on side of tank

2) Copy following links for troubleshoot and repair resources, including service manual by type of gas control valve.
http://waterheatertimer.org/How-to-replace-thermocouple.html
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

3) Get parts sheet from manual that arrived with new product.

4) Otherwise, neither Whitlpool or Craftmaster.has up-to-date product manual, parts sheet, or service manual, rendering their sites near useless for many owners.
Whirlpool site has 'troubleshoot and repair' section, but this is NO help for serious DIY repair.

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

Feb 2013
1) Copy following links for Intellivent gas control service manual, low hot water pressure, and crossover:
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent
http://waterheatertimer.org/Low-hot-water-pressure.html
http://waterheatertimer.org/Crossover.html

2) Unknown if tank has hot water > that is first thing to check.

3) Unknown if air intake screen located under burner is clogged with dust that cause combustion chamber to overheat, tripping FV lockout and breaker TRD glass vial.
Requires removal of combustion parts, replacement of TRD, blow out air intake screen, reset intellivent

4) Unknown if there is error code.

5) Rheem does not post service manuals.
However this unit can probably be repaired.

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

Rheem does not post service manuals, and they say they do not have any.
Call em and ask.
Then ask how their service technicians learn how to repair Rheem products.
There is a general product manual
http://www.rheem.com.au/Assets/1218/1/RheemHeatPump_HDi310.pdf#Troubleshooting
And a possible diagram:
http://www.scribd.com/doc/67528498/6/Chapter-6

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

Before calling service technician, open following link for resources including error codes, Rheem chat and possible manual:
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

Error codes are considered start-point for troubleshooting, and give service technician direction for isolating problem.
Error 82 appears as 'gas type data failure' > 'Program PC board for proper gas type.'

Gas type is choice between LP gas and NG natural gas.
Gas type programming is controlled with dip switch setting.
I do not have service manual for product, and would not suggest changing dip switches without specific information beforehand.

You had service techs and Bosch techs and neither can find a solution.
I assume you want impartial opinion at fixya.
Multiple error codes and a lack of progress by professionals implies PC board failure. BUT there could be multiple problems. Error codes are considered 'start' point for troubleshooting. Beyond that, Bosch should give you contact information to a trained professional service tech >> not just a plumber, but a guy who can do the electronic diagnostic.
Open following link for Bosch troubleshooting resources.
Tankless are high tech gadgets that cannot be exposed to more than 11 grains hardness in the water, and require continual maintenance. The cost of repairs and maintenance will never pay back from the expected $1-8 monthly energy savings.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
You can solve most tankless problems same day for $350.
Then sell the tankless unit back to Lowes or sell it for parts on auction site.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Before calling service technician, open following link for Bosch troubleshooting resources.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Sample manual has troubleshoot section and yearly maintenance requirement.
http://waterheatertimer.org/pdf/Bosch-250SXO.pdf

Service bulletins for 250SXO
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/250SXOTechSupport/ServiceBulletins/tabid/573/Default.aspx

Tankless require yearly maintenance as outlined in manual.
No tankless manufacturer suggests do-it-yourself repairs on their product, in part for liability and danger to customers, but for long-term customer satisfaction.
Repairs and yearly maintenance will eliminate the $1-8 monthly energy savings expected from owning tankless.

Natural gas has a lower pressure/flow rate than propane so through a 3/4" pipe you may not be getting enough at the unit to fire it correctly.
Check that the pipe sizing is correct for the hourly gas consumption of that unit

If I understand correctly, you have electric water heater.
Heater suddenly stopped heating.

Four things cause sudden loss of water heater.
1) Reset button located under the top cover is tripped > turn off power, remove cover, press reset button > if reset keeps tripping, go to the troubleshooting link shown below.
2) Electric power to heater is interrupted > check circuit breaker > test for voltage > look for loose wire on breaker
3) Upper element burned out > test and replace element
4) Upper thermostat bad > replace upper thermostat

Reset button is best suspect.
Here is a link for complete troubleshoot and homeowner repair of electric water heater:
http://waterheatertimer.org/How-to-troubleshoot-electric-water-heater.html

If I understand correctly, you have a tankless water heater.
And the water heater stopped working.
And a plumber stopped by and tested the unit.

Call the original installer.
If you had it professionally installed, call up the installer
The manufacturer will refer you to the installer >>> and the installer has to be certified by their company.

A few questions for you:
was that technician certified and trained by the manufacturer?
If you were to repair the heater, how much would it cost?
Was the technician saying that it was more expensive to repair than replace?
Did he say what was the cause?
Is the circuit board burned out?
Did the circuit board get wet?
Are there pool chemicals and bleach stored in the room that might cause the gas burner to fail?
If the tankless is electric, did the wires burn inside the unit?
Maybe the technician was using the old scare-em sales technique to get you to buy a new one from him.
The lack of information the technician left you makes me wonder his intent.

Tankless water heaters are a nuisance when they don't work because they are complicated systems, and the parts are not available at the hardware store. Your regular tank-type gas heaters have repair issues too, but they don't fail completely after just 4 years. Regular tank-type electric heaters cost more to operate, but the homeowner can repair it same-day with local parts from any hardware store.

Here's a link to operators manual. You can download PDF file as well and print for later use if you wish.

http://bryantrv.com/docs2/docs/operating/atwood1.pdf