Rheem Water Heater 3 flashes: Pressure switch failed open (error 46)
Updated October 2026 · Sourced from Rheem documentation
Three flashes followed by a three second pause. The bulletin says the pressure switch did not close when the inducer ran, which can be a vent blockage, blocked switch tube, blower problem or open over-temperature switch.
Is it safe to keep running? No. Turn it off and get it checked. Call a qualified technician to inspect the venting, blower and pressure switch. Do not bypass any switch.
3 flashes at a glance
| Code / how it shows | Meaning | Applies to |
|---|---|---|
| 3 flashes Gas valve status light: three flashes, then a three second pause. Display models show 46. | Pressure switch failed open (error 46) | Rheem PowerVent ESII gas tank water heaters with Honeywell electronic gas control (gas valve status light flash codes, and display codes on electronic control models) |
Check this first
Only steps a homeowner can do safely. Do not open electrical panels or the burner area.
- Look at the vent outlet outside for blockage (visual check only).
- Power the heater off and back on once to clear the hard lockout, as the bulletin says.
🛑 Stop and call a licensed pro if
- Call a qualified technician to inspect the venting, blower and pressure switch. Do not bypass any switch.
- You smell gas. Leave the house, do not touch switches, and call your gas utility from outside.
- Codes for flame failure, overheating, venting or the control board that return after one reset.
- Water leaking from the heater, the relief valve discharging, or scorching around the burner area.
- A carbon monoxide alarm sounds. Get everyone outside and call 911 or the fire department.
Safe first steps for any Rheem code
- Write down the exact code shown on the controller or the number of status light flashes.
- Turn the water heater power off and back on (or press the reset button the manual describes) once. If the code comes back, stop resetting.
- Make sure the gas supply valve to the heater is open and other gas appliances in the home are working.
- Make sure the cold water supply valve is fully open and hot water taps are not partly closed.
- Look at the outside vent terminal for snow, ice, leaves or anything blocking it (look only).
Source: Rheem Technical Service Bulletin 1627, PowerVent with Honeywell Electronic Control, p. 5. Codes are series-specific, so your unit's own manual is the final word. Reviewed October 2026.
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