Error Code 33; Error Code 34 - Rheem RTG2-42 Troubleshooting Manual

Error Code 33

Explanation: Hot Water Outlet Thermistor has malfunctioned. At a minimum check the
following if you get Error Codes 31, 32, 33, & 34:
1. Check for scale build up on the inlet filter screen. This scale build up could also happen
inside the machine. Scale build up on all thermistors will cause them to be inaccurate.
2. IF maintenance mode shows 32 degrees as the temperature, then the thermistor is not
making connection. (Possibly unplugged, possibly broken wire).
3. IF maintenance mode shows 199 degrees the thermistor has a direct short.
Does the
maintenance
information
indicate the hot
outlet temp?
Yes
The water heater appears to be
normal. Attempt to operate again.

Error Code 34

Explanation: Explanation: Ambient Combustion Air Thermistor has malfunctioned. At a
minimum check the following:
Display maintenance information line [2y] Ambient Air Thermistor temperature.
Does the
maintenance
information
indicate the
ambient air temp?
Yes
The water heater appears to be
normal. Attempt to operate again.
Display maintenance information line [5y] Water Inlet Thermistor temperature.
Is the resistance
to the hot outlet
thermistor OK?
Yes
Is the resistance
No
to the ambient
air thermistor
Yes
56
SVC 810 Tankless Troubleshooting Manual
No
Measure the resistance of connector R
between Black#3 and Red#4 wires:
4k - 19 k ohms
Replace Printer Circuit Board
No
OK?
Measure the resistance of connector R
between Black#3 and Blue#7 wires:
0
6k (93 F) - 19 k (38
Replace Printer Circuit Board
Replace Hot Outlet
Thermistor
Replace Ambient Air
Thermistor
0
F) ohms