I am not an appliance technician, but older dryers are very simple machines when you get down to it. They are essentially a heater, a motor, a timer, and a bunch of sensors. Dryers can and do however start fires if not properly maintained or repaired, so calling a trained appliance technician may be your best course of action.
If this is an electric dryer and you are able to do some basic troubleshooting however, you can get an idea of what component is faulty with a simple ohm meter to check the heating circuit - which of course should start with the dryer unplugged!
Before doing anything else after accessing the heater compartment, I recommend a good cleaning by vacuuming and removing all easily accessible lint. It makes it nicer to work on and is good fire prevention.
The heater circuit typically consists of just three components, the heater element itself, identifiable as the tube looking thing with coiled wires in side, a high temperature fuse, and a temperature control switch. Failures of a component in this circuit comprise the cause of the vast majority of electric dryers failing to heat. All three will typically be daisy chained together in series making it a simple process to determine what has failed.
An ohm meter for a properly functioning circuit should show a very low resistance from one end of the circuit to the other. If any one of the three components is bad, the meter will usually show the circuit as open. You can isolate which component is defective from there by metering each one individually for high resistance or an open circuit.
If the problem is elsewhere in the system, it may be a good time to pick up the phone and get a technician on site. Troubleshooting the other sensors and controls in the dryer are a simple process if you know what you are doing, but figuring out where everything else connects and how it should test is a little more complicated, and consequently easier to screw up.
The high temperature fuse and temperature control switch are often sold in pairs with good reason. A failed temperature control switch may not test open. So a failure of the the temperature control switch can often lead to tripping the high temperature fuse, which does not reset. This happens because the temperature control switch is not shutting off the power when the heater is over temperature. So if either one fails, REPLACE BOTH!
It is important to note that if removing the main heater connection to replace the element itself, technicians will also typically replace the spade clip and wire that attaches to the element from the longer of the two wires. It is subjected to a lot of heat from the element and will fatigue to a point where it loses flexibility if it is wiggled around or disconnected and replaced.
So if you determine that the heater element itself is bad, plan on replacing that piece of wire with an inexpensive heater wire kit as well. Failing to do so can result in a fire. For whatever reason, these two parts are often sold separately, but replacing both is the safest course. It doesn't cost much, is easy to replace, and is good insurance.
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I am not an appliance technician, but older dryers are very simple machines when you get down to it. They are essentially a heater, a motor, a timer, and a bunch of sensors. Dryers can and do however start fires if not properly maintained or repaired, so calling a trained appliance technician may be your best course of action.
If this is an electric dryer and you are able to do some basic troubleshooting however, you can get an idea of what component is faulty with a simple ohm meter to check the heating circuit - which of course should start with the dryer unplugged!
Before doing anything else after accessing the heater compartment, I recommend a good cleaning by vacuuming and removing all easily accessible lint. It makes it nicer to work on and is good fire prevention.
The heater circuit typically consists of just three components, the heater element itself, identifiable as the tube looking thing with coiled wires in side, a high temperature fuse, and a temperature control switch. Failures of a component in this circuit comprise the cause of the vast majority of electric dryers failing to heat. All three will typically be daisy chained together in series making it a simple process to determine what has failed.
An ohm meter for a properly functioning circuit should show a very low resistance from one end of the circuit to the other. If any one of the three components is bad, the meter will usually show the circuit as open. You can isolate which component is defective from there by metering each one individually for high resistance or an open circuit.
If the problem is elsewhere in the system, it may be a good time to pick up the phone and get a technician on site. Troubleshooting the other sensors and controls in the dryer are a simple process if you know what you are doing, but figuring out where everything else connects and how it should test is a little more complicated, and consequently easier to screw up.
The high temperature fuse and temperature control switch are often sold in pairs with good reason. A failed temperature control switch may not test open. So a failure of the the temperature control switch can often lead to tripping the high temperature fuse, which does not reset. This happens because the temperature control switch is not shutting off the power when the heater is over temperature. So if either one fails, REPLACE BOTH!
It is important to note that if removing the main heater connection to replace the element itself, technicians will also typically replace the spade clip and wire that attaches to the element from the longer of the two wires. It is subjected to a lot of heat from the element and will fatigue to a point where it loses flexibility if it is wiggled around or disconnected and replaced.
So if you determine that the heater element itself is bad, plan on replacing that piece of wire with an inexpensive heater wire kit as well. Failing to do so can result in a fire. For whatever reason, these two parts are often sold separately, but replacing both is the safest course. It doesn't cost much, is easy to replace, and is good insurance.