ERROR 76 REFERENCES NEGATIVE - Water Heaters

Copy following links:
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html
http://waterheatertimer.org/pdf/Tankless-error-code-76.pdf
http://www.fixya.com/support/t2655330-paloma_tankless_gas_water_heater

Error code 76 can indicate PC board failure, or remote control failure.

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

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 links for Rheem tankless resources including error codes and Rheem chat.
Disconnect wires from remote to see if system stabilizes. Unit will heat to default temperature without remote.

Error codes are considered start-point for troubleshooting.
C8 76 can mean PC board failure.
76 can mean communication failure with remote control
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html
http://waterheatertimer.org/pdf/ErrorcodeTroubleshooting.pdf
http://waterheatertimer.org/pdf/Rheem-error-code-C7-76.pdf

Error code 76 is communication problem between remote control and tankless unit.
http://waterheatertimer.org/pdf/Rheem-error-code-C7-76.pdf
Multiple error codes could indicate that main PC board is bad.
Before calling service technician, open following link for troubleshooting resources including link to Rheem chat, manuals, error codes, etc.
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

New remote control costs $99/ June 2011
Error 76 is communication problem between remote and water heater.
Open following link for step-by-step troubleshoot, and Rheem tankless resources.
http://waterheatertimer.org/pdf/Rheem-error-code-C7-76.pdf
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

Error code 76 has to do with communication fault with remote
Error codes here: http://www.palomastore.com/paloma_error_codes.html

I am a free answerer, and I specialize in giving you resources for free
The paid answerers may have a person who knows your product and the error codes
The manual will also have the error codes.
The person who installed the unit will also know the error codes (or should know)
Each day I see 20-25 unanswered questions about tankless water heaters.
The number of questions shows the complexity of the machines, and the inability of the manufactures to take care of their customers.
The manufacturer will refer you to the installer.

http://www.thetankatwaterheaterrescue.com/forums/forum3/

http://www.rheem.com/products/tankless_water_heaters/
The link above goes to Rheem tankless water heaters
Click on a product and it opens a page showing many tankless models
Click 'more information' and another page opens with spec sheets and other pdf
Not surprisingly there are no troubleshooting steps or troubleshooting flowcharts
There are plenty of ways to buy a tankless
There are not many ways a do-it-yourselfer can fix a tankless

F76 is a communication error between two quick connected heaters. To clear the code, disconnect power from both heaters, wait 20 seconds, then reconnect power.

76 is a bad connection between the controller and the unit. try unplugging the controller and running it, also check the wiring between the two units. if that is not it. it means that one of the control boards it shot