How to Diagnose Tumble Dryer Control and Program Problems

Hi I'm Josh from eSpares, and in this video I'll be helping you to diagnose control and program problems in your tumble dryer.

Now tumble dryers come in two types, vented and condenser. Vented dryers tend to be a simpler design primarily just using an element and a motor, and the timer on a vented dryer is similar to a simple time switch found on quite simple microwaves.

Condenser dryers on the other hand tend to be a slightly more complicated design. As the name suggests they use a condenser to extract the moisture from the air as it passes over it, before then putting the air back into the wash load to help dry.

Safety First! Please make sure that you’ve switched off your appliance and disconnected it from the mains before beginning any repair.

Now the first fault we're going to have a look at is if your dryer is blowing a fuse as soon as is it switched on. In most cases this is caused by the presence of a short circuit and it's most likely that the short will exist in the heating element although it can occasionally crop up elsewhere.

On this particular dryer, although the heater is located on the back the connections to it are actually inside the dryer, so to get to them I first need to remove the top off the dryer and then remove the side panel. Okay so now I've got the top and the side panel off, I'll just turn it round, now the connections to the heater are here so if I just pull this plug out, I'm going to grab a multimeter and place it onto a low resistance setting and just place the probes of the meter onto the two terminals inside the plug to the heater.

For a working heater I'm looking for reading of between 20 and 50 ohms, here I'm getting about 25 - 26 ohms, that shows that the element should be okay.

Now it can sometimes be the case that you do that test when the fuse is blowing and the reading you get on the meter would show that the element is still working, of course if it's blowing fuses than you know that's not the case. Now, that can be caused by the presence of a short to earth perhaps caused by a bra wire coming into contact with the element. The way to test that is to just place one of the probes onto one of the terminals in the plug and place the other probe onto the metalwork of the appliance, now if there is any short circuit going to earth you will get a reading on the meter, but here I'm not getting any sort of reading so that shows that there isn't a short present. If your dryer is causing the electrics to trip, this can be caused by a leakage of current to earth.

The way to test that is quite similar; it can show up just by placing you meter onto a highly resistant setting and then placing one of the probes onto one of the terminals inside the plug, and the other probe onto the metal work. Now if there is any sort of leakage again you should get some sort of reading on the meter. In this case I'm not getting any reading so that shows that circuit is complete and there isn't any leakage or short present.

Now another cause of a blowing fuse is a faulty mains filter, a mains filter is fitted in most tumble dryers and it's designed to stop interference from getting into the circuit. You can test the mains filter for the presence of a short circuit, just grab your meter and place it on a low resistance setting and trace the wires back from the filter. In this case they go into this plug here so I'm just going to place the probes of the meter onto the terminals inside the plug.

Any short circuit is going to show up is a reading at less than 3 or 4 ohms. In this case I'm not getting the reading, but if you are reading a short circuit disconnect the filter and check again. If that's removed the short-circuit, the fault is with the filter, on the other hand if disconnecting the filter doesn't get rid of the short-circuit try disconnecting the motor and the element and testing again for a short.

If the short has gone that would indicate that it lay in the motor as we've already tested the element. On the other hand if removing the motor and the element doesn't get rid of the short circuit it’s most likely to be in the control board and you need to replace it.

If you do have any sort of faults related to the control board in the dryer it can be quite difficult to actually prove the presence of the fault. The control board is responsible for turning on and off all the different circuits in the dryer such as the heating circuits and the motor circuit.

If your condenser dryer has a pump which pumps water from down at the bottom up into the reservoir at the top it will also have a pump circuit. If you are experiencing a problem with any of those areas in your dryer it's much better to test the individual circuit first before suspecting that the problem lies with the control board. Obviously once you've tested the circuit and you haven't found the presence of a fault, it’s most likely the fault will be in the control board itself and you need to replace it.

Now if you need help diagnosing any other faults in your tumble dryer check out our other videos. Spares for tumble dryers along with other appliances are available on the eSpares website.

Thanks for watching.