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Bosch Dishwasher E09 Error Code – Dishwasher Repair Bath
Bosch Dishwasher E09 Error Code
Heat Pump Failure – What It Means & How We Fix It
What Does E09 Mean?
The E09 error code on your Bosch dishwasher indicates a heat pump failure. This means your dishwasher has detected that the heating system isn’t working properly – so your water isn’t reaching the temperature needed for effective cleaning and drying.
You might notice that dishes come out still dirty, with soap residue, or are cold and wet at the end of the cycle. The dishwasher may complete its cycle, but without hot water, it’s not actually cleaning properly.
Important: While you can technically run the dishwasher with this error, we don’t recommend it. Without heated water, your dishes won’t be hygienically cleaned, and you’re wasting energy running ineffective cycles.
What Causes E09 Error Code?
1. Hard Water Buildup (Very Common in Bath)
Bath has some of the hardest water in the UK. Over time, limescale deposits build up on the heat pump element, causing it to overheat and fail. This is by far the most common cause we see locally. Regular use of dishwasher salt helps prevent this, but once the damage is done, the heat pump usually needs replacing.
2. Low or Empty Dishwasher Salt
If your salt reservoir runs empty, hard water minerals attack the heating element directly. Even a few weeks without salt in a hard water area like Bath can cause significant damage. If your salt light has been on for a while and you’re now seeing E09, this is likely why.
3. Worn Heat Pump Element
Like any heating element, the heat pump has a lifespan. After 5-8 years of regular use, the element can simply wear out. If your dishwasher is older and you’ve always maintained it well, this is probably normal wear and tear.
4. Water Leaks in the Base
If water leaks into the base of the dishwasher, it can short out and damage the heat pump element. This sometimes happens with older machines where door seals or hose connections have deteriorated. The E09 error is the result of the water damage to the electrical components.
Can You Test for E09?
The simplest way to confirm the heat pump has failed is to run a quick wash cycle and check the water temperature:
✓ Run a short cycle
Start a quick wash program. After 20-30 minutes, carefully open the door (watch for steam). If the water inside is cold or barely warm, the heat pump isn’t working.
E09 means a professional repair: The heat pump element needs replacing. This isn’t a DIY fix – it requires dismantling the dishwasher, testing components, refitting and securing a new heat pump to the sump assembly of the dishwasher.
How We Fix E09 Errors
When you call Bath Washco for an E09 error, here’s what we do:
1. Diagnose the exact fault
We test the heat pump element and wiring, and check for further problems – sometimes an underlying issue can be the cause of a heat pump failure.
2. Replace and test
We replace the heat pump element and reassemble your dishwasher. Repair usually completed within an hour. We run a full cycle to confirm the repair, and give you advice on preventing the problem returning (mainly: keep that salt topped up in Bath’s hard water!).
Need E09 Error Fixed in Bath or Somerset?
We’re Bosch dishwasher specialists serving Bath, Chippenham, Trowbridge, Keynsham, Melksham, Radstock and surrounding areas. Over 30 years experience, Which? Trusted Traders.
Email: glen@bathwashco.com
Related Bosch Dishwasher Problems
• E15 Error Code – Water leak detection
• E24 Error Code – Drainage problems
• All Dishwasher Repairs – Our main repair services
Which? Trusted Trader