We are having to re-set our Bosch tankless water heater continually. It frequently displays the Error reading, We re-set, wait and sometimes have to re-set again. What is causing it to shut off and give us the "error" display over and over and how can we fix it.

H2 wasnt an error code on those machines... could you check the display and ask again?

Here's Bosch's A2 error code pdf:
http://waterheatertimer.org/pdf/Bosch_A2_error_code_troubleshooting.pdf

Want the truth?
I answer Bosch, and other brand water heater questions at fixya.
Never, ever install a tankless water heater unless your wallet is 2" thick and you enjoy nuisance problems that you can occasionally fix yourself plus doing recommended continual maintenance.
Tankless with never pay back, otherwise the news would be filled with stories of people saving money. The only reports of savings comes from sellers of the product. Averages savings on gas bill is $1-8 per month, but all costs are energy.

I cannot recommend a solution to fix the Bosch problem if trained service reps cannot solve problem.
If other product-owners report same problem with that model, then problem is likely related to software and/or PB-board problems, which is same as saying your computer motherboard is no good. And most people know that when a computer motherboard has failures, then the computer is unreliable and should be replaced.
Always research a product before buying.
You can solve most tankless problem yourself, same day, no waiting for parts, Sept 2011, for about $350.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Sell the defect tankless for parts, or get up to $12 per 100 pounds for scrap metal at the recycler.
Other resources that you can read:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Richland tankless is made by Rheem.
C7-76 is communication fault with remote.
Turn off power at remote and wait 5 minutes, turn power back on at remote, and see if problem clears.
If problem continues, read below:

Before calling service technician, open following links for troubleshoot resources including error codes, Rheem chat, typical maintenance manual:
http://waterheatertimer.org/pdf/Rheem-error-code-C7-76.pdf
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

Tankless water heater, more than any other type of heater, need to be maintained.
Maintaining tankless will probably not affect C7 76 fault code, but can prevent many other common error codes.
http://waterheatertimer.org/pdf/Tankless-maintenance.pdf

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

Tankless water heaters require yearly maintenance to check gas pressure, inspect and clean burner and combustion parts, inspect vent and vent drain, clean air filter, check water flow, de-lime the heat exchanger etc.
This maintenance can stop ordinary problems from occurring, and can be done by the homeowner by reading Bosch service manuals for specific model number.
The continual maintenance, and cost of repairs and parts, and cost of professional service are more expensive than expected $1-8 monthly energy savings from owning tankless.

Fix most tankless problems yourself, same day, for about $350.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Question posted under Boasch tankless. Model number not known.
Before calling service technician, open following link for Bosch troubleshooting resources, including phone and contact for Bosch, error codes, and possible manual, plus hours of reading and research:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

As you know from reading manual, tankless water heaters require yearly maintenance by trained service technician, or by homeowner. This action would check gas and pressure, venting draft, condensation drain, burner and combustion parts, igniter and-or pilot light, electrical connections, air intake and general condition of plumbing.
Problem you describe does not include error code.
Open following link for possible help with general plumbing problem:
http://waterheatertimer.org/pdf/No-Error-Code.pdf

Add a comment with model number that appears on side of unit, and I can directly locate possible service bulletins and further troubleshoot resources available at Bosch for possible do-it-yourself diagnosis and repair.

Before calling service technician, open follow links for troubleshooting resources.
Bosch site does not show TF250, but shows 250SX and 250SXO.
Gas Products Technical Support: 800-642-3111
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/tabid/370/Default.aspx

At no time when visiting tankless website have I read suggestion that people fix tankless as a do-it-yourself project. In fact each site says repeatedly to call service technician for installation and repairs.
When reading service bulletins, the repair protocols are generally long and very sequential, even if a thermocouple seems straightforward there are many interrelated parts and sensors that must communicate exactly with each other.
Example: following pdf outlines operation sequence for non-standing pilot model
http://waterheatertimer.org/pdf/Tankless-gas-operation-overview.pdf

The dirty water also suggest that tankless has not gotten regular maintenance that is required for continued operation. Tankless are not install-it-and-run-flawless-for-years type of machine.
Read manual for specific maintenance required for your model. For example yearly flushing the heat exchanger with vinegar to avoid lime build-up is suggest most models. Tankless are succeptible to lime build-up.
All costs are energy. Maintenance alone can easily eat up the promised $1-8 monthly savings from tankless vrs tank-type water heater. One service call can wipe away years of expected savings, plus replacement part can sometimes cost as much as whole new tank-type water heater, installed.

You posted under Bosch tankless water heater.
The suspect is probably gas supply, gas valve, or gas related part inside tankless unit.

Before calling service technician, open following link for Bosch tankless troubleshooting resources, including Bosch contact information, typical manuals, error codes, tech support, parts, fuel-saver calculator, service bulletins, water heater forum, fixya links, disclaimers, and links for finding service technician.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Read manual cover to cover, make sure tankless receives yearly maintenance as outline in manual.

Add a comment with your experience so others with same-similar problem can benefit.

Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

1) BOSCH website shows error codes.
FO does not appear:
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/2400ESTechSupport/Troubleshooting/tabid/1295/Default.aspx

2) I do not see FO error code listed on Internet search
Other FO questions at fixya seem to have no answer:
http://www.fixya.com/tags/error_f0_bosch

3) At this point, I would suggest calling a service technician.
While waiting for service, read manual cover to cover several times.

4) Your manual is valuable resource, and shows the word 'maintenance' and 'troubleshoot' frequently.
Tankless are maintenance heavy, and should be de-limed each year.
U-tube search "delime tankless water heater."

5) Also explore Bosch website for your manual and other valuable information.

6) When service tech arrives, ask that person for tips and tricks about your unit that will help you maintain your water heater.

7) All costs are energy. Install DIY tank-type gas water heater and avoid the whole headache.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Check L1 error code on following site:
http://www.palomatankless.com/owners/homeowner+trouble.lasso

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