Water Softener Troubleshooting

Rheem Water Softener Error Code? Check the Drain and Switch First

A Rheem water softener error code usually means the control lost position, a motor or switch signal is missing, or the board sees a valve fault. Start with power, bypass position, and one clean reset before parts.

If the display works and house water still runs, sort reset trouble from valve movement trouble. A repeated Err code needs wiring, motor, switch, cam, leak, and brine clues checked in order.

Clear it once, watch the next recharge, and stop for heat, wet controls, repeat trips, or water stuck running to drain.

Don’t start with: Do not start with a control head or board. Those parts are expensive and model-specific, and a loose connector, wet valve area, stalled motor, salt issue, or drain/brine fault can point a different direction.

Screen blank?Check the outlet, transformer, cord, and any switch-controlled receptacle before opening the unit.

Err code returns?Use bypass if water is running oddly, then sort motor movement, switch feedback, and brine/drain behavior.

Do this first

Keep dry hands around the outlet, transformer, cord, display, and control housing.
If water is running to drain and will not stop, put the softener in bypass and protect the floor before more testing.
Unplug the softener before removing a cover or touching wiring, connectors, the switch, or the motor area.
Stop if the plug, transformer, or outlet feels hot, smells burnt, shows discoloration, or trips a GFCI again.
Stop if water has reached the control board, motor, switch, wiring, or nearby outlet.
Do not force the bypass handle, valve parts, or plastic fittings; cracked softener plumbing can turn a small error into a leak.

Prepared by: Repair Riot Last updated: 2026-05-31 How we build and check guides

60-second error-code sort

Is the display blank or scrambled?

Check the outlet, transformer, cord, and any switched receptacle first. If the outlet is live but the screen stays blank, the power supply or control path needs model-specific diagnosis.

Does the code clear and stay gone?

Set the clock and basic settings, then watch one recharge. If the display stays readable and the code does not return while the valve advances, treat it as a power or position glitch.

Does the same Err code come right back?

Write down the exact code and model number. With power disconnected, look for the clue that comes with it: a loose connector in a dry control area, a motor that only hums, or a valve that will not advance.

Is the softener also leaving hard water or high water in the salt tank?

Check salt bridging, drain restrictions, brine line kinks, and whether the brine level changes during recharge before treating it as only an electronics problem.

Is water leaking or stuck running to drain?

Put the softener in bypass, keep water away from the control area, and stop if normal controls will not shut the flow down.

Is it an RHW42 with Err07, Err08, or Err09?

Err07, Err08, and Err09 point to the RHW42 motorized shutoff-valve path. If the unit is an RHW42 and those codes return, check for a shutoff valve that stays stuck or will not advance. Use the manual or Rheem support guidance before guessing at salt, brine, or a generic board.

Read the cabinet before you read the parts list

On Rheem cabinet-style softeners, the error code is only one clue. The display, outlet, bypass handle, salt tank, brine tube, drain line, and dry control area all matter before a board or valve part makes sense.

Rheem style cabinet water softener with control display, outlet power, bypass plumbing, and open salt compartment — Start with the whole cabinet. A readable display, dry control area, steady outlet power, salt condition, and brine path tell you more than the code alone.

Rheem style softener transformer cord bypass valve brine tube and drain tube checked while dry — Keep the power and control area dry. A loose transformer cord, wrong bypass position, kinked brine tube, or poor drain route can change the diagnosis before parts.

Open water softener salt tank checked for a salt bridge with a blunt wooden handle — A tank can look full from the top and still have a hollow salt bridge underneath. Probe gently before adding more salt.

Before you buy anything

Write down the exact Rheem model number, the exact Err code, and what the display does after one reset. Note whether the motor tries to move, and whether the salt tank, brine tube, drain line, or control area is wet. Control boards, motors, switches, rotor/seal kits, transformers, and shutoff-valve parts are model-specific.

Jump to: Step-by-step fix · Tools You May Need · Replacement Parts

What is probably happening

A Rheem error code starts with the code on the display, but the cabinet clues decide the branch. Look at power, dry controls, salt condition, brine draw, drain flow, and whether the valve moves before calling it a board, feedback, or valve-movement problem.

Err01, Err03, and Err04 usually point toward the wiring harness, switch feedback, valve position, or motor operation.
Err05 points toward a possible control board fault, but possible does not mean proven.
Err07, Err08, and Err09 on RHW42 models belong on the motorized shutoff-valve path.
A blank screen is a power path first: outlet, transformer, cord, wiring, and dry control area.
Hard water, high salt-tank water, or no brine draw can ride along with an error code and make the control look guilty.
A good clue is whether the motor tries to move and whether the valve advances through recharge instead of stalling.

What not to do first

Do not let one code turn into a cart full of parts. The softener needs a short, clean diagnosis before money is spent.

Do not order a control board just because the display says Err.
Do not keep clearing the same code without watching what the motor, valve, drain, and brine side do next.
Do not add salt until you check for a salt bridge or packed salt hiding under the surface.
Do not open covers or handle connectors while the softener is plugged in.
Do not force a stuck bypass handle, valve cover, tubing clip, or plastic fitting.
Do not ignore wet controls, hot electrical parts, repeat GFCI trips, or a unit that will not stop draining.

Step-by-step fix

Work from safe outside checks toward model-specific parts. If the softener gives you a stop clue, stop there.

Step 1: Keep the control area dry. If the softener is leaking or sending water to drain nonstop, put it in bypass and protect the floor.
Step 2: Check power. Make sure the plug and transformer are seated, test the outlet with a small known-good device, and reset a GFCI once only.
Step 3: Clear the code once. Restore power, let the display boot, set the clock if needed, and see whether the same Err code returns without a recharge.
Step 4: Write down the exact code and model number. Err05, RHW42 shutoff-valve codes, and motor/switch codes do not lead to the same part.
Step 5: With power disconnected, look under the top cover only if you are comfortable doing it. Look for loose connectors, corrosion, water tracks, or a disconnected motor or switch plug.
Step 6: Run a manual recharge only after the area is dry and the softener responds normally. Listen for the motor and watch whether the valve advances instead of humming in one spot.
Step 7: Check salt, brine, and drain behavior during the same run. No brine draw, high water in the salt tank, or weak drain flow can explain a repeat fault.
Step 8: If the code returns after dry power checks and a clear brine/drain path, move to model-specific motor, switch, rotor/seal, board, or shutoff-valve diagnosis.

What the results usually mean

Use the result, not the first guess. This table keeps the repair branch from drifting.

What you find	Likely branch	Next move
Blank screen with a dead outlet.	House power or switched receptacle.	Restore safe outlet power before softener parts.
Blank screen with a live outlet.	Transformer, wiring, or control path.	Check dry connectors and exact model before parts.
Code clears and stays gone.	Power blip, lost settings, or temporary valve position.	Set the clock and watch the next recharge.
Err01, Err03, or Err04 returns.	Harness, switch, valve movement, or motor path.	Look for loose dry connectors, then move to model-specific testing.
Err05 returns.	Possible control board fault.	Rule out power, wet controls, and loose connectors before buying a board.
Motor hums but the valve does not move.	Motor, cam/gear, rotor/seal, or valve binding.	Stop before forcing parts; use model-specific service guidance.
Salt tank water is above the salt or brine never draws down.	Drain, brine line, brine valve, or internal seal path.	Fix the water-movement clue before blaming the display.

Salt and brine checks that still matter

A real Err code can still show up beside a plain brine problem. Look for the water-side clue before the repair turns into electronics.

Open the salt lid and look for a hard crust, hollow bridge, packed mush, dirty salt, or water standing above the salt.
Probe straight down with a blunt handle. If it drops through a hollow shelf, clear the bridge gently before adding more salt.
A small amount of water at the bottom of the salt tank can be normal. Water above the salt moves the job toward drain, brine draw, or internal leak checks.
During recharge, watch for the brine level to change instead of sitting still through the draw stage.
Look for a kinked brine tube, salt crust at fittings, a loose drain line, or a drain route that cannot flow freely.
If salt, brine draw, and drain flow all look normal but the code returns, watch whether the motor hums or the valve stalls. Those clues move the fault toward valve movement, switch feedback, motor drive, seals, or the control path.

Tools You May Need

Use these for basic inspection and cleanup. They are not permission to probe energized wiring or open parts you cannot put back together.

Paid links. As an Amazon Associate I earn from qualifying purchases. Repair Riot may earn a commission at no extra cost to you.

Inspection flashlight

Helps when: You need to see the outlet, transformer, bypass handle, top-cover area, brine tube, drain line, or salt tank without pulling the softener apart.

Skip it when: The check would put your hands near wet controls, damaged wiring, or powered internal parts.

Compare inspection flashlights on Amazon

Bucket and towels

Helps when: You are drying the floor, catching a small drip near tubing, or keeping water away from the outlet and control housing.

Skip it when: Water is spraying, the softener will not stop draining, or water has reached electrical parts.

Compare cleanup supplies on Amazon

Blunt wooden handle

Helps when: You need to check for a salt bridge without reaching deep into the salt tank or hitting the cabinet walls.

Skip it when: The brinewell, float, or internal tank parts are loose, cracked, or in the way.

Compare wooden handles on Amazon

Water hardness test strips

Helps when: You want to check whether the water improves after a completed recharge and a short flush at a nearby faucet.

Skip it when: You are trying to identify an electrical code or board fault. Hardness strips prove water result, not control diagnosis.

Compare hardness test strips on Amazon

Replacement Parts

Buy only after the code, symptom, or test result points to a part and the exact Rheem model number and valve design match. A lookalike softener part can still be wrong, so compare before ordering.

Paid links. As an Amazon Associate I earn from qualifying purchases. Repair Riot may earn a commission at no extra cost to you.

Water softener transformer

Helps when: The outlet is live, the cord is dry, connectors look intact, and model-specific diagnosis points to a failed power supply or transformer.

Skip it when: The outlet is dead, wet controls are present, or the display works and the code points to valve movement instead.

Compare softener transformers on Amazon

Clear replacement brine line tubing for a water softener with small fittings nearby

Water softener brine line

Helps when: The brine tube is kinked, cracked, brittle, loose at the fitting, packed with salt, or pulling air during recharge.

Skip it when: The line is clear and dry, or the exact problem is a motor, switch, board, or shutoff-valve code.

Compare brine lines on Amazon

Water softener rotor and seal kit parts laid out near a Rheem style softener

Rheem rotor and seal kit

Helps when: Power, connectors, salt, drain, and brine checks are clean but the valve sticks, leaks internally, misroutes water, or will not complete recharge.

Skip it when: You have not matched the exact model and valve design, or the problem is a blank display or RHW42 shutoff-valve code.

Compare rotor and seal kits on Amazon

Replacement water softener control board module near a cabinet style softener control housing

Rheem control board

Helps when: Buy a control board only if Err05 returns or the screen stays blank after you check steady power, dry controls, connector seating, and repeat behavior. Match warranty status and the exact model number before ordering.

Skip it when: You are buying because any Err code appeared, or because salt, drain, brine, motor, and switch clues have not been checked.

Compare control boards on Amazon

FAQ

Can I just clear the Rheem water softener error code and keep using it?

Clear it once using the normal reset or recharge sequence, then watch what happens next. If the same code comes back during idle time or recharge, treat it as a real operating fault instead of a random display glitch.

Why does my water softener show an error code after a power outage?

A brief outage can leave the control out of position or wipe out time settings. Check the outlet and transformer first, then reset the clock and run one observed recharge before buying electrical parts.

Does an error code always mean the control board is bad?

No. Rheem error-code troubleshooting also points at wiring, switch feedback, valve movement, motor behavior, water in the control area, and model-specific shutoff-valve faults. A board belongs in the cart only after the easier clues stop explaining the code.

What if the salt compartment has standing water when the error shows up?

Some water at the bottom of the salt tank can be normal, but water above the salt is a different clue. Check the drain path, brine line, and whether the tank draws down during recharge before treating the code as only an electronics issue.

When should I replace a water softener seal kit?

Consider a rotor and seal kit only after power, connectors, drain path, brine line, and salt condition are checked and the unit still sticks, misroutes water, leaks internally, or cannot complete recharge. Match the exact model and valve design.

Should I add more salt if the softener is showing an error?

Only after checking for a salt bridge or packed salt. Adding more salt on top of a hard crust can make the problem worse and hide the real issue.

What do Rheem Err01, Err03, or Err04 usually point to?

Rheem groups those codes around the wiring harness or switch, valve trouble, or motor operation. Start with dry, unplugged connector checks and visible water or corrosion clues before moving into motor or valve diagnosis.

What does Rheem Err05 mean?

Rheem describes Err05 as a possible control-board malfunction. Possible is the key word: confirm steady power, dry controls, secure connectors, exact model number, warranty status, and repeat behavior before ordering a board.

What if my RHW42 shows Err07, Err08, or Err09?

Those codes are tied to the motorized shutoff valve on RHW42-style models. Use the RHW42 manual or Rheem support path for that branch rather than treating it like a basic salt or brine-line problem.

Can I test the water softener motor myself?

You can listen for the motor and watch whether the valve advances during a normal recharge. Stop before powered open-cover testing unless you are trained and equipped; unplug before removing covers or touching wiring.

When should I call for service instead of resetting again?

Call for service if the outlet trips again, the transformer or plug feels hot, or water reaches the control area. Also stop if the unit will not stop draining, the motor hums without moving, or the exact replacement part is not clear.

How this guide was built

Repair Riot built this page from Rheem's public troubleshooting paths, owner-manual pages, and homeowner-safe checks. The order is dry power first, one reset, exact code and model, then brine/drain and valve movement before parts.

Rheem water softener support — Manufacturer water-softener context and support path for model-specific troubleshooting.
Rheem water treatment systems — Manufacturer context for Rheem water-treatment equipment and support resources.
Rheem water softener support path — Manufacturer support path for model-specific motor, valve, and control questions.
Rheem water softener troubleshooting context — Manufacturer water-softener support context before model-specific drain, brine, or valve work.
Rheem water treatment support — Manufacturer context for salt-tank and softener support resources.
Rheem water softener model support — Manufacturer support path for current Rheem water softener model information.