The cycle starts but no water comes in, so nothing gets washed. On a Thermador dishwasher this usually traces to the water supply, the inlet valve, or a safety feature doing its job — and several of these you can check yourself.
No water coming in? Call 844-975-6696 or book a visit.
Quick guide
| What you’re seeing | Likely cause | Fix it yourself? |
|---|---|---|
| No water at all | Supply valve off or inlet valve | Check the supply first |
| Won’t start filling, door pops open | Door not latched | Yes — close it firmly |
| Fills slowly or partly | Clogged inlet valve screen | No — needs service |
| Dead, and there’s water in the base | Anti-flood tripped by a leak | No — needs diagnosis |
Check the easy things first
Before assuming a part failed, confirm the basics: the water supply valve under the sink is fully open, the supply line isn’t kinked, and the door is latched (the dishwasher won’t fill if the door isn’t closed properly). These three account for a lot of “won’t fill” calls.
What causes it
- Supply valve closed or kinked. No water reaches the dishwasher.
- Failed or clogged inlet valve. The electric valve that lets water in has failed or its screen is blocked.
- Door not latched. The cycle won’t fill unless the door is fully closed.
- Stuck float. A float stuck in the “full” position tells the dishwasher not to add water.
- Anti-flood tripped. If a small leak put water in the base pan, the overflow protection stops it filling.
No water in means nothing gets clean — if the real complaint is dishes coming out dirty, see why dishes are still dirty.
Step-by-step: what to check
- Open the supply valve. Check the shutoff under the sink is fully on and the hose isn’t kinked.
- Latch the door firmly. Make sure it clicks shut and nothing blocks it.
- Check the float. Confirm the small float in the tub moves freely and isn’t stuck up.
- Listen for the inlet valve. A faint hum with no water suggests a clogged or failed valve.
- Look for anti-flood. If it’s dead and there’s water in the base, the overflow protection has tripped on a leak.
When to call a technician
Book a visit soon if the supply is on, the door latches, and it still won’t fill — or if the anti-flood has tripped. The inlet valve and float switch are meter-tested before replacement, and a tripped anti-flood means finding the leak that set it off, not just resetting it. Book Thermador dishwasher repair so the cause is found, not just the symptom.
It can wait if it was simply a closed supply valve or an unlatched door — that’s an easy self-fix.
What the repair actually involves
A technician confirms water pressure at the supply, then meter-tests the inlet valve for the right operation and checks the float switch. A failed valve is replaced (a defined part, mid category), or the float switch if that’s at fault. If the anti-flood tripped, they trace and fix the underlying leak first. The main cost driver is the valve versus a leak repair. You get a written estimate before any work, and the common fill parts are stocked for a single visit.
Is it safe to use until then?
Yes — a dishwasher that won’t fill can’t cause harm, it just won’t wash. The one exception is if the anti-flood has tripped: that means there’s already water where it shouldn’t be, so leave it off and get the leak checked before running it again, especially in an apartment.
Preventing it
- Keep the under-sink supply valve fully open and the hose free of kinks.
- Close the door firmly until it latches every time.
- Address small leaks early before they trip the anti-flood.
Frequently asked questions
Q: Why won’t my dishwasher fill with water?
A: Most often the supply valve is off or kinked, the door isn’t latched, or the water inlet valve has failed. Check the supply and door first; if those are fine, the inlet valve or float switch needs testing.
Q: What is the water inlet valve?
A: It’s the electrically controlled valve that opens to let water into the dishwasher at the right point in the cycle. When it fails or its screen clogs, no water — or too little — comes in, and it’s replaced as a unit.
Q: Why is there water in the base and the dishwasher won’t start?
A: The overflow (anti-flood) protection has tripped. It detects water in the base pan from a leak and shuts the dishwasher down to prevent a flood. It needs the leak found and fixed, not just a reset.
Q: Can a stuck float stop the dishwasher filling?
A: Yes. The float rises with the water level to signal “full.” If it’s stuck in the up position — often from debris — the dishwasher thinks it’s already full and won’t add water. Freeing it usually solves it.
Get the water flowing again
If the supply is fine and it still won’t fill, the inlet valve needs testing. We handle Thermador dishwasher repair with a written estimate before any work starts.
Call 844-975-6696 or book online. Same-day service is usually available in New York, Los Angeles, Chicago, San Francisco, Houston, and Miami.