Washing Machine Not Heating
If you think your washing machien isn't heating the water then read this first
We see this problem crop up fairly regularly on the forums and sometimes there is a fault but, often times there’s not.
Ordinarily the reported symptoms will be the the owner of a washing machine doesn’t think that the machine is heating, it’s not heating correctly or along the lines of the user cannot feel any heat in the door or after the wash is complete.
But how do you really know if there is a problem and if your washing machine really is or isn't heating properly?
In order to understand what’s going on and to help you get to the bottom of the problem we need to explain a number of things in a little bit more detail.
Washing Machine Heating Element
The water heating element in your washing machine has two simple states. On and off.
A common misconception is that the heating element in your washing machine will ramp up and down in a variable type fashion but they do not at all, ever, they are simply on or off. They either have continuity on test or they do not, the resistance value for failures is largely irrelevant in virtually all instances.
The on and off is normally controlled by (these days) a triac and/or relay on the electronic control board. The control board gets the information to switch it on and off to reach and maintain the temperature via what program you select and when the small thermistor or sensor reports the current water temperature to be.
The heater simply cycles on and off as required and it is powered on and off by the control board as it detects is needed by way of the sensor.
So if it goes a bit whack-a-doodle on you the element will go open circuit and faulty or, the thermistor can fail in the usually thermistor type way that you can find out about in other articles in this and the spare parts sections.
There are some that have earth leakage problems but this isn't so common and tends to throw up all manners of crazy, not usually a straight no heat fault.
What Indicates A Faulty Wash Heater
Now you know that there are only two states you can probably work out that the heating element in your washing machine is really rather a dumb thing broadly speaking.
In most modern machines the electronic control board will “look” for the element by trying to see if it can detect a circuit across the heater. If it is open circuit it won’t be able to, throw it’s teddies out and chuck up a fault code or some blinking lights to tell you there’s a problem.
On older machines the washer would just stop and sit there forever with water in it looking rather forlorn.
The important thing to understand here and the point is that, if the heater is faulty the machine cannot heat and it will in some way abort the program.
The logic in washing machines is, will we say, not great. If they encounter a problem or fault they don’t know how to solve it as they are really rather dumb things in some ways. So it will just sit there looking dumb until someone tells it what to do next or, sorts the problem.
No Heat In The Door Or Laundry
With modern machines and low temperature washes, which is what most people do, you will generally speaking not feel much if any heat through the door glass. And, when you do it’s only on the wash part of the cycle.
But what with big thick glass doors and low temperature washing most people probably wouldn’t be able to tell.
The only way to know for sure is to throw a data logger in the machine and read the temperature that the water is reaching on a wash cycle. Anything else without testing components for failure is pretty much just guesswork.
And the reason you won’t feel any heat in the laundry after the cycle is completed is because all washing machines should rinse on cold water only. If you do feel heat after the machine is done then you’ve probably got an installation problem, not a problem with the machine.
Wash Results Not Good
This brings us nicely onto a pretty common set or problems that we mentioned earlier, complaints about wash results and the user suspecting that this is down to a fault with the heater.
It almost never is.
As we have explained the wash heater largely either heats or it doesn’t, there’s really no in between and no way for it to affect the performance really. Other than if it's failed obviously but then, that's obvious enough.
That said, it has been widely reported that some machines do not get to the set temperature or to be more accurate, they do not reach the indicated temperature that people think they are setting.
Many modern machines have the likes of a 40˚C cotton wash indicated on the panel but that’s not actually what it is. What it is really is a program that the manufacturer has deemed to be an equivalent program for that HLCC wash code that satisfies the requirement of that wash label.
Our opinion is that this is a bit of a sham at best, a total deceit at worst and is probably there to make the energy rating label look wonderful. The reality being that sure, it uses less energy but it will never hit the temperature that the user thinks it will.
But it also makes the modern machines far, far more sensitive to error on the part of the user.
As in, if you do not use the exact correct wash cycle for the wash label on the clothing then the machine will be far less forgiving of that error and the usual result will be, poor wash results.
The conclusion of the user is often that, as the machine doesn’t seem to be washing and they cannot feel any heat in the door or after the wash that the machine is not heating correctly and that this is the cause of the poor results.
To many people that would seem perfectly logical and reasonable.
But, in virtually every single instance if the machine does not stop and completes the cycle without any errors then then the heating element in your washing machine is just fine.
You just might have to adjust to compensate for the continual drive to lower energy ratings.
And yes, we agree with most people on this when it’s discussed. It’s completely bonkers.