Electric Dryers...?

Question

I bought a used electric dryer, It was in great condtion and worker wonderfully the first few weeks but all of a sudden it stopped putting out hot air and now only cold air.. Everything is working fine expect for the air not being hot. i tried to adjust the settings and even cleaned out the lil bit of lint that was in the dryer and still have had no results... What can I do to fix this problem so I can start using my dryer again? Serious answers only please..

Answer 1

my very old model whirlpool does not heat up and the element is fine. what else could be the problem and how do I fix it?

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Before you even open the dryer, use your voltmeter to measure for 240v at the dryer wall outlet. You can't just look at it and think it's fine (I actually get people telling me that!) And just because the dryer motor runs, this doesn't mean you're getting 240v at the outlet, either. The motors runs on 120v but the heating elements require 240v and a common problem is for one leg, L1 or L2, of the 240v supply to open. If you're not getting 240v at the dryer outlet, you'll never get the elements to heat up. Plain n' simple. Whether you have a four-prong outlet or a three-prong outlet, you gotta check the voltage at the outlet with a meter!

Ok, so you checked the voltage at the outlet and you actually measured 240v on your meter. Now, and only now, we turn our keen, laser-like attention inside the dryer. Let's look at an example wiring diagram for an electric dryer. This one happens to be for a Whirlpool/Kenmore electric dryer and is probably very similar to yours. In the diagram, the heating element is shown in the lower right hand side. L1 and L2 are drawn on the either side of the diagram. The heating element connects to L1 and L2 through several different components. L1 connects to the heating element through the timer, a thermal cutoff, the operating thermostat, and the hi-limit thermostat. The heating element then connects to L2 through the motor centrifugal switch. All it takes is for any one of these components to fail open and this would prevent the heating element from receiving the needed 240v to get hot. Again, even though the example diagram is for a Whirlpool/Kenmore electric dryer, this is a typical configuration for any electric dryer.

Although any one of these components can kill the voltage to the heating element, there are a couple that tend to fail more commonly and can be easily checked. A quick and easy test to do is to measure the continuity of the thermal cutoff, the operating thermostat, and the hi-limit thermostat. Do this with the dryer unplugged and your meter set on the Rx1 scale. Disconnect at least one wire from the component being tested to isolate it from the rest of the circuit. If you find one that's open, replace it and problem solved!

While you're checking the continuity of these things, check the wiring for burnt or loose connections--this is another common cause for no-heat in electric dryers. If all those check out, then that leaves the the timer and the motor centrifugal switch.

Easiest way to test the timer is to run the dryer and measure for 120v out of the timer pin that powers the heating element circuit--in our example, it's pin R. Measure for this voltage by setting your meter to the 150vac scale and placing one probe on timer pin R and the other on any metal point on the dryer frame. Oh, I know what you're asking, "But if the heating element needs 240v, why are we only measuring for 120v at the timer?" The heating element gets its 240v in two halves: 120v from L1 and 120v from L2. We're only looking for the L1 half at the timer so we're looking for 120v.

Finally, if the timer voltage checks good, then that only leaves the motor centrifugal switch which, if you've made it this far in your checks, you can safely assume is bad. Since the centrifugal switch is an integral part of the motor, this means you have to buy a new motor. A manufacturer's repair manual and an AllenBar take a lot of the frustration out of this job. (search for the manual of that model online)



http://www.applianceaid.com/faq-dryer.html#elecheat

My electric dryer runs but will not heat, what could stop my dryer from heating ?

A - Things that could stop a electric dryer from heating:

- house fuse or breaker ( needs 2! )... - heating element ... - burnt wire ... - thermostats ... thermal fuse ( not all models )... - motor heat switch ... - timer ... - selector switch ... - burnt power cord/plug ...

A ohm meter test for these parts is here.

Can anybody tell me the most likely scenarios for lack of heat in an electric dryer?
There are many things that can cause a no heat symptom in an electric dryer, here is a list of possible causes in order of likelihood or ease of access.

An open fuse/breaker in the house fuse panel.
There are 2 fuses or breakers for the dryer, both must be good in order for the dryer to function properly. If one is open, it is possible for the dryer to run but not generate heat. In the case of breakers, try resetting them as sometimes one of the two can open but not physically tip the mechanical lever.



The illustration above shows how the main dryer motor and the timer's motor can continue to operate with one of the two fuses for the dryer open as they operate on 120 volts only. The working circuit could also include a light which is not illustrated.


An open thermal fuse in the dryer.
Some models use a thermal safety limiter or thermal fuse which could open the circuit to the heat element. These are used to prevent a runaway or over heat condition and are often found mounted to the blower or heater element housing (see the links below for examples). These devices are a fairly current development and may not be found on very old dryers.


Note: If this is the cause of your current problem (pardon the pun), I strongly suggest you check the vent for obstructions and ensure its length meets the manufacturers recommended limitations, the shorted the better. Failure of this part could be the first indication of a potential fire hazard in the dryer!

The element coil is burnt out.
Dryer elements are bare wires coiled like springs, when they fail the wire will break opening the circuit. This breakage could be intermittent, only opening as the element expands as it heats. Sometimes the element coil has to be physically checked for breakages, especially where the coil goes through ceramic insulator which could hide a breakage from plain view.



Depending on the brand and style, the replacement element may be just the coiled wire that has to be mounted into the original element housing. On other models the element assembly comes already mounted on a frame that then in installed into the element housing or directly into the dryer. Whichever the case, the element coil has to be replaced not just joined together using connectors.

Open switches.


These can include the heat selector switch mounted on the console panel, one of the thermostats (from 2 to 5 on some models) mounted in various locations of the internal dryer ducting, the motor switch or the heater contacts of the timer or a 'heater relay' on newer models with an electronic heat control mechanism.

A link below explains dryer thermostat's operation in detail.


A burnt wire or wire connector.


Replace the burnt wire connector and/or wire and inspect the component terminal it was attached to. If any sign of charring or discoloration are visible on the component's terminal or repeated failures occur at that same location, replace the component the terminal is part of. Such items can include the main power junction terminal block (very common), thermodiscs (thermostats), heat selector switch, centrifugal switch (on the motor) or the timer.



How do I test for continuity?

How long can my dryer vent be?

Repair Parts : Showcase : Dryer Thermostats

*Thermal fuse locations on some Whirlpool, KitchenAid and Kenmore dryers

*Thermal fuse location on some Norge, Magic Chef and Maytag dryers

*Thermal fuse location on some Frigidaire, White Westinghouse and Gibson dryers

*Thermal fuse location on some newer GE and Hotpoint dryers

Using crimp-on connectors

Answer 2

it could be that the heating element in the dryer is no longer working. shouldn't be too expensive to fix.