Dishwasher
I20
The I20 error code on a Hotpoint dishwasher is a drainage fault — the appliance has detected that water isn’t draining away as it should, or not quickly enough. It’s one of the most common dishwasher faults in UK homes and, reassuringly, it’s also one of the most fixable without calling out an engineer. In this guide, you’ll learn exactly what’s triggering the I20 code, the most likely culprits, and a practical step-by-step process to get your dishwasher draining properly again.
What does this error mean?
The I20 code is Hotpoint’s way of telling you there’s a problem with water drainage. Specifically, the dishwasher’s control board has detected that water is not leaving the machine within the expected timeframe during or after a wash cycle. The appliance uses a pressure sensor (sometimes called a pressure switch or level sensor) and a drain pump to manage water removal. When the pressure sensor still detects standing water at a point in the cycle where the drum should be empty — or when the drain pump runs but water levels don’t drop — the control board logs the I20 fault and halts the programme to prevent flooding. In short: water is stuck inside your dishwasher and it can’t get out. The fault itself doesn’t mean your dishwasher is broken beyond repair — it means something is blocking or interrupting the drainage path.
Est. repair cost
£0 for a DIY filter clean; £20–£45 for a DIY drain pump replacement; £80–£140 for a professional repair including call-out and labour
🔍 Likely causes
🛠️ Step-by-step fix
Step 1 — Reset the dishwasher first: Before anything else, switch the dishwasher off at the mains, wait 60 seconds, then turn it back on and try starting a new cycle. Occasionally a temporary pressure sensor glitch triggers I20 and a hard reset clears it. If the error returns, move on to Step 2.
Step 2 — Scoop out standing water: If there’s water sitting in the bottom of the tub, use a large sponge or a cup to remove as much as possible before you start investigating. This keeps things manageable and lets you access the filter clearly. No special tools needed — just an old towel to hand.
Step 3 — Remove and clean the filter assembly: Twist and lift out the cylindrical filter from the base of the tub, then remove the flat mesh filter beneath it. Rinse both under a hot tap, scrubbing with an old toothbrush to remove grease and food debris. If there’s heavy limescale, soak in a solution of white vinegar and warm water for 15–20 minutes. Refit both filters correctly — the cylindrical one should click back into place securely.
Step 4 — Check and clear the drain pump housing: With the filters removed, look down into the sump area with a torch. You should see the drain pump inlet — a small circular opening. Carefully reach in (wear rubber gloves) and feel for any debris, glass fragments, or objects blocking the impeller. Remove anything you find. Try rotating the impeller gently with a finger — it should spin freely. If it’s stiff or won’t turn, there may be a foreign object lodged further inside.
Step 5 — Inspect the drain hose for kinks or blockages: Pull the dishwasher forward slightly (turn off the water supply first) and check the corrugated drain hose at the back. Straighten out any obvious kinks. If you suspect an internal blockage, disconnect the hose from the waste pipe end (have a bucket ready) and check that water flows freely through it. A simple garden hose or tap can be used to flush it through.
Step 6 — Check under the sink for blockages: Look at where the dishwasher drain hose connects to your kitchen waste. Run the hot tap and check the sink drains freely — if it’s slow, clear the under-sink trap first (you’ll need a bucket and an adjustable spanner or slip-joint pliers). A partially blocked sink trap is a surprisingly frequent cause of the I20 fault.
Step 7 — Verify the drain hose high loop: Check that the drain hose is routed up to the underside of your worktop before dropping down to the waste connection. This high loop prevents dirty water siphoning back into the machine. If the hose runs straight down without looping, use a cable tie or hose clip to secure it up to the inside of the cabinet at worktop height.
Step 8 — Run a test cycle and observe: Refit everything, run a short programme (a rinse cycle works well), and watch and listen during the drain phase. You should hear the drain pump running as a distinct higher-pitched hum. If you hear it running but no water is expelled, the pump impeller may still be jammed or the pump has failed. If you hear nothing at all during drain, the pump motor has likely failed.
Step 9 — Consider a DIY drain pump replacement: If the pump motor has failed, replacement drain pumps for common Hotpoint models (HSFO 3T223 WX, HFC 3C26 W, HIO 3T223 WFE and similar) are widely available from UK suppliers such as eSpares, 4ourhouse, and Repair Aid for £20–£45. Replacing the drain pump involves removing the lower kickplate and tilting the machine — it is physically straightforward for a confident DIYer who is comfortable working around appliances. Always unplug the machine at the mains before attempting this. If you’re not confident working with the internals, skip to Step 10.
Step 10 — If in doubt, call a professional: If you’ve completed Steps 1–8 and the I20 fault persists, or if you’re not comfortable accessing the pump, the fault is likely a failed pump motor, a faulty pressure sensor, or a wiring issue. These are best left to a qualified appliance engineer. Do not attempt to open the control board or interfere with wiring — this is not a safe DIY task.
📞 When to call a professional
You should call a professional appliance engineer if: the I20 error persists after you’ve cleaned the filters, cleared any visible blockages, and checked the drain hose and sink waste; you can hear the drain pump running but no water is moving (likely a seized impeller or failed pump needing internal access); there is no sound from the drain pump at all during the drain phase (motor failure); the drum is empty but the I20 error still appears after a reset (possible pressure sensor or wiring fault). When you call, tell the engineer: the exact error code (I20), the make and model of your dishwasher (found on the rating plate inside the door frame), what you’ve already checked (filters, hose, sink waste), and whether you can hear the drain pump running. This will save time and may reduce your call-out cost. For most UK homeowners, a reputable local appliance repair company or a Hotpoint-approved engineer via the Hotpoint website (0344 822 4224) are both good options.
⚖️ Repair or replace?
For most I20 faults, repair is clearly the right call — especially if the cause is a blocked filter or drain hose, which costs nothing to fix yourself. If the drain pump has failed, a replacement part costs £20–£45 and a professional repair (including call-out and labour) typically runs to £80–£140, which is very reasonable compared to a new dishwasher costing £300–£700. The key question is age: if your Hotpoint dishwasher is under 7 years old, repair is almost always worth it — parts are readily available and the machine has plenty of life left. If it’s over 8–10 years old and the pump failure is accompanied by other issues (leaking, poor wash results, noisy operation), it may be approaching the end of its economical life and replacement becomes more sensible. Hotpoint is a widely sold brand in the UK, meaning parts and engineers familiar with the range are easy to find, which works in your favour for repairability. One practical tip: if the engineer quotes more than 50% of the cost of a comparable new machine, it’s generally better to replace.