Broken Tumble Dryer Belts
If your tumble dryer belt is snapped or burned through then the chances are, we're sorry to inform you, that it is almost certainly your fault. Or, the fault of the person using the tumble dryer.
The reason is really rather obvious when you think about it and there is usually no other possible explanation for a drive belt to fail, especially so when it supposedly "snaps" or "burns through".
We will explain why this is.
Snapped Tumble Dryer Belts
The most common failure we see on tumble dryer drive belts are where one section of the belt has become burnt through, as shown in the image lifted at random off the internet to the right.
What you see is one small section of the belt glazed over or burnt through while the rest of the drive belt looks absolutely fine for the most part. Although, for serial offenders, there may be other small areas that are affected, it just didn't quite get to the point where the belt broke.
The cause, when you think about it is startlingly obvious.
In some way, the tumble dryer has been overloaded to the point where the drum cannot turn so the belt stops moving and the motor pulley continues to spin burning its way through the drive belt.
A tumble dryer can be overloaded by putting too much laundry in it or, by putting laundry that is too heavy into it, both have the same effect, they stop the drum from moving.
Any other possible reason for this too happen, such as a jockey pulley or tensioning wheel that's faulty or the motor itself will be glaringly obvious to almost anyone looking.
Outside of these there is really no other possible explanation for a tumble dryer belt to snap.
Why The Reason For Failure Is Obvious
The reason that this is so obvious to any competent service engineer is that you can see that a dryer drive belt has usually only two or three points of contact, the drum itself that it is to turn, the tensioning pulley and the motor drive pulley.
There is almost no possibility whatsoever that, given the massive area of contact, that the drive belt can slip around the drum because the force required would be massive and, there's two other areas of less resistance to slip on first.
The tensioning wheel is just that, it is a free running wheel and whilst these can go faulty it will normally be the case that they get noisy, to have one jammed would be at best a million to one shot. This will often have more surface contact with the belt than the motor pulley, again making it extremely unlikely that the belt would slip here even it if were to jam somehow.
That leaves us with the motor drive pulley, which is the (usually) grooved metal pulley that drives the belt. This is the point of least resistance and, the point at which the belt is almost certain to slip and so, it does.
What this gives is this very obvious tell tale of what caused the fault, the drum has stopped moving but the motor kept on going and burnt its way through the belt due to friction.
Belts & Warranty
This is the reason why on tumble dryers and washing machines, that drive belts are often not covered by warranty and are classed as "wear and tear" items therefore, even whilst covered by warranty, failures of this nature may well not be covered and you may well have to pay to have your tumble dryer repaired.
Please understand that belts in washing machine and tumble dryers are a part that, in normal use, will rarely if ever fail of their own accord. There is always a reason it failed as most have a design life that will extend beyond the life of the appliance.
Of course for service engineers this is an issue, most people aren't exactly over the moon when we tell them this. And so, no customer that experiences this kind of failure (like most other customer generated faults) has ever done anything wrong, they didn't overload it etc and the fault should be repaired free of charge, the Sale Of Good Act gets rolled out, threats to go to Watchdog, Trading Standards and so on. It really is most often very predictable and, tiresome if we were to tell the truth.
The thing is, the evidence says one thing quite clearly and yet, the owner says exactly the opposite of what the physical evidence says. You can see how that can be a problem.
Some manufacturers will wear the fault once but, if it happens again they are very likely to reject the fault as a warranty repair because it is infinitely more likely that the user is a serial overloader than another belt has failed.
Unless you can come up with a really, really good explanation for some sort of failure that could cause this, you are liable to get charged.
The same thing goes for a belt replaced outside of warranty. Any service engineer worth his salt and, most of them are pretty bright and have seen this many times, is going to know this and, if it fails again with the same symptoms he will almost certainly charge you again to repair it once more.
Keep in mind though, this isn't a fault of the machine or the drive belt, it's a use issue.
How To Avoid Belts Snapping
Apart from stressing the belt, the motor and tension pulley you're also running the risk of blowing thermostats, things not getting dried correctly, burning up electricity needlessly and a myriad of other possible issues. With extreme cases creating a possible fire risk.
It is absolutely vital that you do not overload your appliances, including your tumble dryer.
To blow air through the laundry and dry properly and, economically, you must allow a good amount of space in the drum for the laundry to move about it, if you don't then you're wasting electricity and running the risks outlined above.
We recommend that you do not fill the drum of your dryer to beyond about half to three quarters of the door opening at the most.
Also, do not put sopping wet items in your tumble dryer or the load, even when a lower level than above, can prove to be too heavy and that will also stop the drum from turning and snap the belt.