Rheem Water Heater Error Code 7 (07 or 7 Flashes): What It Means by Model (Meaning, Causes, Fixes)

What the code means

Rheem uses the number 7 in three different places. (1) Gas tankless, WiFi models: Rheem's High and Super High Efficiency Tankless Troubleshooting Manual (AP21822) lists 07 as "Warning Code - Limited hot water condition." It is shown only when the WiFi controller is used, and it appears when the heater is controlling the water flow rate because water saving mode is set. Rheem describes water saving control as an optional feature, off by default, that reduces flow at the start of a hot water draw until the outlet water reaches the set temperature, recommended for drought areas. (2) Gas tank heaters with a standing pilot and a status light on the combination gas control (for example Performance models such as XG40T06EC36U0): the Use and Care manual's status light chart lists seven blinks every three seconds as "Combination gas control failure" (the label reads Gas Control or Valve Failure), and the solution is to contact a qualified service technician. One blink every three seconds is normal; 2 is low thermopile voltage, 4 is a high temperature shutdown, 5 is a temperature sensor failure and 8 is a false pilot flame signal. (3) PowerVent tank heaters with the Honeywell electronic control: Rheem Technical Service Bulletin TB 1627 lists Seven Flash, three second pause (display code 47) as a flammable vapor sensor lockout. The control immediately shuts off the gas valves, inducer and ignition and goes into a hard lockout. Count the flashes and check your heater's label before acting, because the fix is completely different for each type.

Likely causes

• Tankless WiFi models (07): water saving mode is turned on, so the heater deliberately limits flow until the water is hot. This is a warning, not a failure.
• Standing pilot tank models (7 blinks): the combination gas control, which is the gas valve and thermostat in one unit, has an internal failure, per Rheem's status light chart.
• PowerVent Honeywell models (7 flashes, code 47): gasoline or another flammable vapor reached the flammable vapor sensor near the bottom of the heater.
• PowerVent Honeywell models (7 flashes, code 47): a flammable vapor sensor whose resistance has drifted out of range (Rheem's normal range is about 11 to 45 kilohms), which also keeps the heater locked out.

Safe DIY checks

1. First identify your heater. A digital display showing 07 is a tankless heater. A blinking light on the gas valve at the front of a tank is a status light code; count the blinks between the three-second pauses.
2. Tankless 07: no repair is needed. If you'd rather have full flow right away, the water saving setting is changed with DIP switch 1 (third switch) and the Max or Min button on the control board, per Rheem's manual. That means removing the front cover with the gas, water and power off, so have a qualified person do it if you aren't comfortable.
3. Standing pilot tank, 7 blinks: turn the gas control knob to OFF. Rheem's chart says to contact a qualified service technician; there is no owner reset for a failed gas control.
4. Before calling, check that the status light really shows 7 blinks and not 4 (high temperature) or 2 (low thermopile voltage), which have different fixes.
5. PowerVent, 7 flashes or code 47: if you smell gasoline, paint thinner or another solvent, don't operate any switches near the heater, ventilate the area and remove the source. Leave the building and call your gas utility if you smell gas.
6. Once the area is clear of vapors, Rheem's bulletin says the hard lockout clears only when power is manually cycled, the control dial is rotated through the HOT setting 7 times within 30 seconds, and the vapor sensor reads within its normal range.
7. If code 47 returns with no vapor source nearby, stop resetting it and have the sensor tested.

Parts that commonly fix it

Always match the part number to your exact model.

Related codes

• 62 Bradford White Water Heater 62
• 0 Rheem Gas Furnace 0
• 11 Rheem Gas Furnace 11
• 30 Rheem Gas Furnace 30
• 57 Rheem Gas Furnace 57

All Rheem codes →

Sources

1. Rheem High and Super High Efficiency Tankless Troubleshooting Manual AP21822, p.63 (07 Warning Code: Limited hot water condition, WiFi models only) and section 1.6.3 Water saving control
2. Rheem Eagle Tankless Use and Care Manual AP22009 (Water Saving Control: optional, off by default, DIP 1 switch 3 and Max/Min buttons)
3. Rheem Performance XG40T06EC36U0 Use and Care Manual, p.25 (Combination Gas Control Status Light Troubleshooting: seven blinks every three seconds = combination gas control failure), via ManualShelf
4. Rheem Technical Service Bulletin TB 1627, PowerVent with Honeywell Electronic Control (Seven Flash = error 47, flammable vapor sensor lockout; sensor 11-45 kilohms; hard lockout reset)