Bosch Dishwasher Error E09 – Heating Fault – Heat Pump Not Heating
The Bosch sees no working heater circuit. On most models the heater is built into the circulation pump.
At a glance
Severity: Moderate
- Meaning
- Heating Fault – Heat Pump Not Heating
- System
- Bosch · Dishwasher
- Typical repair cost
- $0–$600
- DIY difficulty
- Hard
Current Bosch dishwashers don't have an exposed heating coil in the tub. The heating element is wrapped around the housing of the circulation pump, a part Bosch calls the heat pump, and water is warmed as it is pumped past it. When the control switches the heater on and finds an open circuit, it stops the cycle and shows E:09, usually a few minutes after the start. In most cases the heater element inside the heat pump has burned open; less often a corroded plug at the pump, a tripped protector or the control board is to blame.
How it looks on the display
Model families & display variants
| Model family | Shows | Note |
|---|---|---|
| 100, 300 and 500 Series (display on the top edge of the door) | E:09 | Only visible with the door open. The cycle stops and the remaining time disappears. |
| 800 Series and Benchmark | E:09 | Same code and meaning on the larger display; these models use the same heat pump design. |
| Older Ascenta, Integra and Evolution models | E09 | Shown without the colon. Earlier generations with a separate flow-through heater use the same code for the heater circuit. |
| Models without a numeric display | blinking LEDs | The fault is signaled by an indicator pattern that differs by model; the table is in the use and care manual. |
Safety first · Consult a professional
Turn off the breaker before pulling the unit out or touching any connector; Bosch units in the US are often hardwired, so unplugging is not always possible. Water in the sump and the pump housing can still be hot right after the code appears.
- Unplug the appliance or switch off the breaker before opening any panel. Mains voltage can kill.
- Water and electricity: unplug first, keep towels ready and never stand in water while the appliance is connected.
- Hot surfaces and hot water can cause burns. Let the appliance cool down first.
Symptoms
- E:09 on the display a few minutes into the cycle, program stops
- Dishes and tub are cold and wet when you open the door
- Water in the tub never feels warm, even with a hot supply line
- Poor cleaning and heavy water spots on earlier loads, before the code appeared
- Code sometimes follows an E:15 episode, when a leak dripped onto the pump
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Heating element in the heat pump burned open
- Corroded or loose connector at the heat pump, often after water dripped onto it
- Thermal protector on the heat pump tripped or failed open
- Heater relay or driver on the control module failed
- Wiring harness chafed or pinched under the tub
Fix it step by step
Do one full power reset
Hold Start for about 3 seconds to cancel, then switch the breaker off for five minutes. Run a Normal cycle and open the door after 10 to 15 minutes: the tub should feel clearly warm. If E:09 returns, the heater circuit is really open.
Rule out the obvious water supply issue
Run the kitchen faucet until hot water comes out, then start the dishwasher. A hot supply around 120°F shortens the heating phase, but it does not cause or cure E:09, so the code returning with hot water confirms an electrical fault.
Pull the dishwasher out
With the breaker off and the water valve closed, remove the toe kick and the two mounting screws at the top or sides, then slide the unit out. Keep towels ready: the supply line and drain hose still hold water.
Tools: Screwdriver, Towels & shallow pan
Inspect the heat pump connector
Lay the unit on its back on a blanket and remove the base cover. Look at the heat pump in the center: check the heater plug for green corrosion, melted plastic or a loose fit, and look for white scale trails that show an old leak.
Tools: Flashlight, Screwdriver, Gloves
Measure the heater resistance
Unplug the heater connector and measure across the two heater pins. On US 120-volt models a healthy element reads roughly 10 to 20 ohms; an open reading (OL) means the heat pump has to be replaced. Check the pins to the metal pump body too: any reading there means a short to ground.
Tools: Multimeter
Decide on the repair
If the element reads fine, the fault is in the harness or the control module and belongs with a technician who can check the output under load. If it reads open, the heat pump is replaced as a unit together with its seals and clamps.
How to reset E09
- Press and hold Start for about 3 seconds to cancel and pump out.
- Switch off the breaker for about five minutes so the control fully restarts.
- Restore power and start a Normal cycle. If E:09 reappears within the first minutes, the reset did not fix a physical fault.
Where the parts are
- 1Door lock
- 2Water inlet valve
- 3Filter
- 4Circulation pump
- 5Heating element
- 6Drain pump
- 7Float switch
- 8Temperature sensor
- 9Water level sensor
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Power reset and hot-water test | Yes | $0 |
| Clean and re-seat corroded heat pump connector | Yes | $0–$25 |
| Heat pump replacement, DIY (part only) | Yes | $150–$300 |
| Heat pump replacement by a technician | No | $350–$600 |
| Control module replacement | No | $250–$500 |
Rough US estimates; technician call-out fees vary by region. Not a quote.
When to call a technician
Call a technician if you aren't comfortable pulling a hardwired unit out and laying it on its back, or if the heater measures fine but E:09 keeps coming back. On an older dishwasher, get the heat pump quote before deciding: the part plus labor can approach the price of a new entry-level Bosch.
Frequently asked questions
Can I keep using the dishwasher with E:09?
Not really. Most models stop the cycle as soon as the code sets, and even when a program finishes, the dishes were washed cold and won't be sanitized or dried. Wash by hand until it is fixed.
Is E:09 caused by my water heater being too cold?
No. The dishwasher heats its own water and checks its own heater circuit. A cold supply only makes the heating phase longer; it never triggers E:09 by itself.
Why does the whole pump get replaced just for the heater?
On the heat pump design, the heating element is bonded to the pump housing and isn't sold separately. That's why the repair price is higher than on dishwashers with a separate heating coil.
I had E:15 last month and now E:09. Are they connected?
Quite possibly. A leak that set E:15 can drip onto the heat pump connector and corrode it, or the heat pump seal itself may have been leaking. Look for scale trails around the pump when you pull the unit out.
Sources
- Official Bosch user documentation and support pages (facts only; wording is our own)
- Methodology: How We Build Code Pages · Data Sources We Use · Editorial Policy