Rheem 79

Rheem code 79: fan motor current fault

Short answer

Code 79 is a blower (fan) motor current fault on Rheem and Ruud tankless heaters. Rheem's steps are to remove and clean the blower motor and housing and make sure the fan turns freely, then check the motor voltage and replace the fan motor or control board if the code returns. It is often an early warning before a fan failure code 61.

In this guide
  1. What it means by model generation
  2. What a technician does
  3. Prevention
  4. How to reset it
  5. Before you call

The blower pushes combustion air and exhaust through the heater. Code 79 means the motor is drawing more or less current than expected, often because it is dirty, binding or wearing out.

This page uses two Rheem sources: the current Rheem and Ruud tankless troubleshooting manual, and Rheem's error code list for earlier tankless models. Codes can differ between generations, so the meaning for each is shown where they differ. Rheem technical support: (800) 432-8373.

What it means by model generation

Rheem generationMeaning
Current modelsBlower motor current fault
Earlier modelsFan motor current fault

What a technician does

  1. Removes the control board bracket and blower motor.
  2. Cleans the blower and housing and checks that the fan spins freely; Rheem notes it will run with a small amount of restriction.
  3. Checks the voltage to the motor.
  4. Replaces the fan motor or control board if the code returns.

Prevention

Keep dust, lint and pet hair away from the heater, especially in garages and laundry rooms. See Rheem code 61 if the fan fails completely.

How to reset it

  1. Close all hot water taps.
  2. Turn the remote control off, wait about 10 seconds, then turn it back on.
  3. Open a hot tap and watch whether the code returns.

Before you call

Have the model and serial number from the rating label ready, and note whether your unit is a condensing (high-efficiency) or non-condensing model. Tell the technician the exact code, when it appears and any recent work on the gas, water, venting or electrical supply. That often saves a second visit.

See every code on our Rheem error codes page.

Common questions

Is Rheem code 79 the same as code 61?

Both involve the blower. 79 is a current fault, often an early warning; 61 means the fan speed was not right for combustion.

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Other Rheem codes

CodeMeaning
00 Continuous combustion for more than one hour
03 Communication failure between units, remote or manifold controller
05 Improper combustion detected by the flame rod (warning)
10 Air supply or exhaust blockage (hard lockout)
11 Ignition failure
12 Flame failure
13 Poor combustion detected by the flame rod (indoor units)
14 Overheat safety tripped
15 Heat exchanger or hot water temperature too high (boiling safety)
16 Outlet water temperature above the set point (over temperature warning)
21 Air intake filter switch fault (earlier models)
24 Remote control buttons held too long, or operational switch fault
29 Condensate not draining (condensing models) or heat exchanger temperature too low
31 Inlet water temperature sensor (thermistor) fault
32 Heat exchanger thermistor fault
33 Outlet (outgoing water) thermistor fault
34 Ambient or combustion air temperature sensor fault
35 Improper thermistor connection
51 Gas valve fault: flame detected after shutdown (current) / gas inlet solenoid valve fault (earlier)
52 Modulating gas valve (PGFR) fault
61 Blower (combustion fan) motor fault
65 Water volume control valve fault
66 Water bypass valve fault
71 Gas inlet solenoid valve fault
72 Flame rod fault: flame sensed before ignition
76 Remote control communication fault
79 Blower (fan) motor current fault
80 Gas cut-off failure: flame detected after the unit turned off
82 Control board program chip fault (current) / gas type data failure (earlier)
90 Vent blockage detected before ignition
92 Neutralizer needs replacing soon (warning, condensing models)
93 Neutralizer must be replaced; unit will not operate (condensing models)
1L Lime (scale) buildup detected in the heat exchanger
99 Vent blockage detected after shutdown / blocked flue (hard lockout)
P1 Not enough water flow to fire the burner (warning)

All Rheem error codes