Rheem Tankless Water Heater Code 61: Blower Fan Speed Problem (Meaning, Causes, Fixes)

What the code means

Rheem's High Efficiency Tankless Water Heater with Recirculation Troubleshooting Manual (AP24838) calls 61 "Blower motor speed incorrect for combustion": the heater checks the fan's RPM signal after the fan starts, and if that signal is wrong it shows 61. Rheem's SVC 820 pocket troubleshooting manual words it as "The Blower motor speed was not appropriate to allow proper combustion." The older SVC 810 training manual calls it "Combustion Fan Failure" (fan motor does not work properly), and Rheem's tankless Use and Care Manual lists "61 or 99" as "Faulty blower motor. Contact a dealer or qualified service technician." Rheem Australia's continuous-flow list gives the same idea: abnormal fan speed or fan failure.

Likely causes

• A loose or poorly seated connector between the blower motor and the control board (Rheem's first check, and sometimes the whole fix)
• Dust or debris in the blower motor or blower housing, or a fan that doesn't turn freely
• Venting that is too long, has too many bends, or is blocked at the intake or exhaust, so the fan can't move enough air
• Damaged or loose wiring in the harness to the fan motor
• A failed blower motor
• A failed control board that isn't powering or reading the fan correctly

Safe DIY checks

1. Do Rheem's reset: turn off all hot water faucets, turn the heater off with the POWER ON/OFF button, wait about 5 minutes, turn it back on, then open a hot faucet and check the display. If the code is still there, turn the faucet and heater off, unplug the heater for 30 seconds, plug it back in and repeat.
2. Go outside (or to the vent terminations) and check that the air intake and exhaust aren't blocked by snow, leaves, nests, lint or anything stacked against them. Clear anything you find.
3. If the heater was recently installed or the vent was changed, ask the installer to confirm the vent run is within the maximum length and number of elbows in your model's manual; Rheem's older service manual lists over-length venting as a code 61 check.
4. While hot water is running, you can feel for airflow at the exhaust termination; Rheem's service manual asks technicians to confirm some air is coming out of the flue.
5. Don't open the heater's cover or probe the fan connector. Rheem's own procedure involves live DC voltages up to about 195 volts at the blower connector and warns that touching the wrong two wires can damage the blower motor and control board, so leave it to a technician if the reset doesn't clear 61.

Parts that commonly fix it

Always match the part number to your exact model.

Related codes

• 12 Rheem Tankless Water Heater 12
• 13 Rheem Tankless Water Heater 13
• 29 Rheem Tankless Water Heater 29
• 11 Rheem Tankless Water Heater 11
• E012 / 012 / 012E Navien Tankless Water Heater E012 / 012 / 012E
• E109 / 109 / 109E Navien Tankless Water Heater E109 / 109 / 109E

All Rheem codes →

Sources

1. Rheem High Efficiency Tankless Water Heater with Recirculation Troubleshooting Manual AP24838 (61: blower motor speed incorrect for combustion; RPM signal check, reseat connectors, voltage checks, replace board or blower)
2. Rheem Tankless Gas Troubleshooting Pocket Manual SVC 820 (P) (61: blower speed not appropriate for proper combustion; clean blower and housing; connector G voltage checks)
3. Rheem/Ruud Tankless Training Manual SVC 810, 2nd Edition (61: combustion fan failure; fan turns freely, air from flue, harness, venting length and bends)
4. Rheem Tankless Water Heater Use and Care Manual (61 or 99: faulty blower motor, contact a dealer or qualified technician)
5. Rheem Tankless Easy Installation Guide (clearing-alarms reset steps)
6. Rheem Australia hot water troubleshooting guide (61: abnormal fan speed or fan failure)