On the covered Rheem PowerVent water heater, display 46 and three flashes means pressure switch failed open. First, look for anything blocking the vent or air intake outside the house. Then: Rheem's bulletin lists a pressure switch fault delay of 2 minutes for a switch that has failed open or closed. Vent and pressure switch work belongs to a technician.
Differential
Likely causes of “Rheem PowerVent water heater display 46 and three flashes”, and how to tell them apart
- 1
A blocked vent or air intake
What separates it The blower runs but the switch never closes
How to confirm Look outside at the vent and the air intake
- 2
A cracked or loose pressure switch tube
What separates it The tube is split, kinked or off its fitting
How to confirm Look at the tube between the blower housing and the switch
- 3
A failed pressure switch
What separates it The vent is clear and the tube is sound
How to confirm A technician tests the switch with the blower running
- 4
Combustion air starved by a closed room or a new appliance
What separates it The code appears after a door or vent was closed or sealed in the heater room
How to confirm Check that the room's combustion air openings are clear
- 5
A blower that does not run at the start of the call
What separates it No sound from the blower and the display shows 46
How to confirm Listen at the start of the heating call, then call a technician to test the blower
Before you touch a setting
Record this first — changing settings destroys the evidence
- Whether the blower runs
- The three flashes or the 46 display
- What blocks the outdoor vent
- The heater model
- Whether the exhaust terminal outdoors is clear of nests, snow or leaves
- Whether the blower is audible at the start of a heating call
Try in this order
0 of 6 completedWhat to do first
ReversibleLook for anything blocking the vent or air intake outside the house.
Correct only the documented fault domain
ReversibleRheem's bulletin lists a pressure switch fault delay of 2 minutes for a switch that has failed open or closed. Vent and pressure switch work belongs to a technician.
Check the vent outside
ReversibleClear anything covering the vent or the intake without touching the pipe while hot.
Restart the heater
ReversibleReset it once with the control and watch whether the blower starts.
Call a technician
ReversibleRheem lists a two-minute fault delay for a pressure switch that has failed open or closed.
Listen for the blower
ReversibleAt the start of a heating call, stand near the heater and listen. A blower that never starts points at power to the blower; one that runs and still shows 46 points at the vent or the switch.
Model-specific
What is true of this model and not of its siblings
- Shown as
- Display 46, or three flashes.
- Applies to
- Rheem PowerVent gas water heaters with the Honeywell control.
- Reference
- Rheem's technical service bulletin for PowerVent with the Honeywell control.
Stop boundary
When this stops being a self-service repair
- !Vent and switch work belongs to a technician
- !Turn gas off if you smell gas and call the utility
Evidence ledger
Sources behind this answer
Exact questions
Common questions
What does display 46 and three flashes mean on a Rheem PowerVent water heater?+
Pressure switch failed open.
Why does it wait two minutes?+
Rheem's bulletin gives a pressure switch fault delay of 2 minutes.
Is it safe to jumper the switch?+
No. The switch proves the vent is moving air.
Does a PowerVent need a blower to run?+
Yes. The blower pulls exhaust gas out through the vent pipe, and the pressure switch confirms it is moving before the burner is allowed to light.
Can I keep using hot water while it is locked out?+
The tank still holds hot water, but it will not reheat until the switch problem is fixed.