Error Code 13 - Rheem RTG2-42 Troubleshooting Manual

Error Code 13

Explanation: Oxygen Depletion Sensor activated. The unit was not able to resolve an imperfect
combustion issue. At a minimum check the following in all cases:
1. Check for lack of fresh combustion air such as in a tight closet.
2. Check maintenance history to see if this is the first incidence of failure with this code.
Is the ODS
thermocouple
OK?
Measure the voltage of
connector Q between Red
and White wires:
Yes
8 to 30 m VDC
The water heater seems to be normal.
Try to operate again.
If you get error code 13 and you can not seem to locate the problem, then try this to check for a
potential missing sensor damper:
1. Check the wire from the ODS to PCB. A disconnected or loose wire will also show Ø
(zero) voltage in maintenance mode.
2. Recycle unit to main burner.
3. Run the unit for at least 3 minutes in main burner mode
4. Did the unit:
a. Shut down at exactly 2.5 minutes?
b. Never go to EC '05' to try and fix the problem? (ODS generated too low voltage
against minimum required voltage from ODS. The board never "senses" it is in an
ODS failure and never tries to correct itself with the '05' code.)
5. If so:
a. Recycle power and go to maintenance mode.
b. Go to cell ØA.
c. Verify Ø voltage present (that is the correct reading) when main burner is off.
d. Press the ON/OFF button to go to main burner. Turn on a water faucet.
e. Run the unit for at least 3 minutes and watch the display cell ØA.
f. If you get between8 mv and 30 mv, then the ODS and burner are probably OK.
Is the burner
No
manifold
pressure
normal?
50
SVC 810 Tankless Troubleshooting Manual
No
Confirm and adjust burner
manifold pressure. See
instructions on page 39.
Yes Check the following:
* Dirt or blockage of the heat
exchanger or venting. Clean if
necessary.
* Check for dirt or blockage of the
fan motor or air intake on the front
cover. Clean if necessary.
* Check for blockage of the flame
opening of the sensing burner.
Clean the entire burner assy.
including sensing burner.
* Disconnect the thermocouple and
connector. Replace the upper burner
assy. Re-attach the connector firmly.