Dishwasher FAQ

Q: Machine does not fill

A: This is usually the water control valve. You can check if it is being “called” by the control board, by connecting up a test lamp while powered off, then starting a pre-wash cycle. If the lamp lights, then the valve is faulty. Some are “double” hot and cold, some models have separate valves. NOTE: see the next item, because if there is a lot of residual water in the dishwasher, and the sensors detect that water is NOT PUMPING OUT OF THE MACHINE, it is designed to assume that there is an outlet blockage, and will not let it fill.

Q: Machine does not empty

A: This can be caused by a failed pump, pump blockage, or a blocked outlet pipe so check all the obvious first, before taking the pump out. You should be able to unclip the filter, so check if has not got covered with a sheet of that plastic film used to cover food. Also check that nothing like that has worked its way inside, under that. There is sometimes another part that unclips, leading to the pump area, check that is clear. If still no joy, remove the outlet pipe, and ensure there are no blockages from the pump end, or in the pipe. If you DO have to remove the pump motor, you can check it on a workbench. Rig up a mains lead, with appropriate spade terminal push-ons, and a plug fused at NO MORE THAN 5 AMPS. If the motor runs, then it is the control circuitry, or relay at fault. If the fuse blows, then it is probably a shorted motor

Q: Crockery not drying

A: This can be due to a failed heater element, or control circuit, or relay. The most likely is the heater element. Some dishwashers, like MIELE, have an exhaust air fan motor unit, that accelerates the drying time. If this fails, or the motorised valve does not fully open in this unit, the heating cycle may not be long enough to dry all the items. A telltale sign is a small amount of water comes out of the exhaust grille, when the door is opened flat. NOTE: if replacing any element or motor unit, ensure any new seals supplied are fitted.

Q: The glasses are coming out spotty and dull

A: This can be a combination of too little salt, and too little “rinse-aid” getting into the cycle. Check that there is sufficient salt in the salt tank, and that there is enough rinse-aid present. If there is, see if there is an adjustment knob inside the flap where you fill the rinse-aid tank, to increase the amount dispensed (if yours has numbers, move the control to a higher number). A coin is usually needed to move it. If there is an adjustment for salt, try altering that too (on some models, such as MIELE, this is a water hardness adjustment dial inside the dishwasher, on the right side, factory set to 3, try clicking to higher numbers for harder water, with a screwdriver).

Q: My dishwasher trips the RCD/ELCB (from SteveB of Northants).

A: Steve indicated that this was happening on the drying cycle, so this is most likely the heating element in the bottom of the dishwasher. These can deteriorate over time, either with scale and corrosion causing water ingress, or with internal shorts to ground. Replacement is not too difficult. Any old seals should be replaced with new ones supplied with the new element. Also see the link for APPLIANCE SPARES.

Q: My dishwasher is not cleaning the dishes well. What can cause this?

A: This can be caused by the water level being too low during the wash cycle. If this happens, then the pump will not work efficiently, and will not spin the spray arms. Surprisingly, some models open the water valve on a timer, rather that have a level control. This means that if the inlet water pipe has a kink, or is partially blocked, or the pipe-filter is blocked, by the time the (usually 2 minute) timer has completed, there will NOT be high enough water level to provide a good wash cycle. The first thing to check, is that the on/off valve lever is in the fully open position. Second, carefully check the whole length of the inlet water pipe (both hot and the cold if dual hot and cold fill). The third item, often overlooked, is that the little nylon mesh filter in the end of the pipe (the part that screws on to the inlet valve) can be clogged with scale and other debris. On the MIELE G665, (and similar models with a electrical “water-stop” device on the end of the inlet pipe) this can be hard to see, as there is a thick rubber washer that is difficult to remove. Once removed, use pliers to pull out the filter (it often looks OK on the top, but the sides can get clogged). If your hot water pressure is low (often the case where loft header tanks are used), then the small plastic and rubber pressure reducer under the filter can be removed. Pliers can be used to remove this. Another cause of low water pressure or flow, can be the use of those horrible clamp-on “quick-fit” water pipe connectors. These use a small hollow steel cutting tube to make a hole in the copper pipe, and work “OK” for a while, but after a few years, they corrode, gradually blocking the hole. I always replace those with proper inline or TEE appliance valves.

Q: My Hotpoint Aquarius FLD570 does not heat the water and does not dry.

A: This particular fault was caused by a failed heater element in the heater unit – part C00256527. This FAQ and the following procedure kindly supplied by CS of Northamptonshire.

Procedure – have towels and kitchen roll ready, then follow these steps:


Turn off water and power, disconnect water, power and drain so that the machine can be pulled forward. Pull the machine forward carefully ensuring the pipes don’t snag

Get help and roll it onto its side, mopping up any water with an old towel.

Use a flat bladed screwdriver and prize the plastic panel out from the bottom

There is a wire connected to the bottom. Remove this wire. You can now see the pump/heater unit.

Remove the earth lead and power cable for the heater. There is a small nipple on the plug which needs pushing in to enable the plug to be removed.

This leaves the cable on the pump unit at the back still connected.

Use a small screwdriver and grips and prize up the tab on each of the hose clips. Once an end is lifted, use the grips to pull it off. Note the sizes and purchase new hose clips (40mm and 30mm I think)

The pump should slide out from the rubber holder on the base plate now. As the pump comes out, disconnect the power for the pump.


The new unit is only the shell. You will need to remove the top and inner rotor and fit to the new unit.

Place the old unit into a vice or similar that will clamp the unit securely without warping it. IMPORTANT: Note the location of the base holding bracket in relation to the pipes on the body.

Look at the lugs at the top and use a small piece of wood and a hammer and tap the top round to clear the lugs

Pull the top off and remove the rotor

You may want to give it a wash now. Mine was out of action for a while and the stuff inside stunk!

Put the rotor in the new body. Note it has a locating peg to make sure it is seated properly.

Put the new rubber O ring supplied with the body in place.

Locate the top in the correct position (as noted previously)

If like me you didn’t note the position, you will now need to take the unit and top back to the machine and line the pipes up and the bottom bracket. Now you know which lugs to use

Push the top down firmly and evenly over the new O-ring. You can do this with your fingers being careful not to bend the terminal wires on the new body.

With the new pump body secured in a clamp or similar, tap the lid round to lock it back on the lugs.


As with the best of car manuals, this is the reverse of removal. Things to note:

  1. There should be 3 wires attached to the pump – pump, heater and earth
  2. The pipes used are soft rubber so don’t overdo it when tightening the new hose clips
  3. Ensure you reattach the bottom flood sensor, otherwise you will get lots of flashing lights when you turn the machine on.
  4. Don’t forget to attach the water inlet pipe and turn it on, plug power back in, and importantly, reconnect the waste pipe!
  5. Test it before you push the unit back in.
  6. Feed the pipes back carefully and slowly as the unit is returned to its original location, so that nothing gets kinked or trapped.

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