Repairing a Dryer that Won't Start

Having a dryer that refuses to start can be incredibly frustrating. As you stand there repeatedly pushing the start button and get nothing but silence in response, you likely have a lot of questions running through your mind. Why won't my dryer turn on? Do I need to call appliance repair right away or can I fix this myself? How hard is it to troubleshoot and what parts might be causing it to not start?

We'll begin by going over some of the most common reasons a dryer won't start, then review what you'll need to test and replace parts. With some basic tools and safety precautions, you can often diagnose and fix a dryer that won't start without needing to schedule service. Let's begin unraveling the mystery of what's causing your dryer to not power up!

Checking Power to the Dryer

The first thing to check with any appliance that's unresponsive is confirming that electricity is actually making it to the device. Start by verifying that the dryer is plugged firmly into the wall outlet. Check behind the unit, as sometimes the plug can work itself loose over time from vibrations. Make sure you don't see any burn marks or melted areas on the cord. If there are signs of damage, you'll need to replace the power cord prior to further troubleshooting.

Next, take a look at your home's breaker box and locate the switch controlling the dryer circuit. Flip the switch fully off and back on again to reset the connection. If the circuit trips again right away, you likely have a short somewhere in the electrical system or the dryer itself that will need to be addressed. With the breaker on, go back and confirm the outlet has power either with a multimeter or by plugging in a simple test device like a lamp.

Testing Voltage at the Terminal Block

Assuming the outlet proves functional, the next step is opening up your dryer to gain access to the terminal block. This junction connects the external power cord to the internal components. Use a screwdriver to remove the terminal block cover panel and set your multimeter to the appropriate voltage scale.

Touch the meter probes to the outer pins corresponding to hot and neutral. For a 110-120 volt supply, you should see a reading within that range, likely at 120v. If voltage measures significantly lower or none at all, there's likely a wiring issue back to the electrical panel or service drop outside.

Possible No Power Causes

• Power cord unplugged from wall
• Outlet failed or not functional
• Tripped breaker or blown fuse
• Damaged or faulty power cord
• Wiring issue from breaker panel to outlet
• Bad terminal block connection

Inspecting the Door Switch

Assuming adequate power is confirmed, the next most likely culprit for a no-start dryer is a failed door switch. This safety mechanism prevents the drum from spinning when the door is open. Locate the switch assembly mounted in the door frame and use your multimeter probes to check continuity with the door both closed and open.

You should only hear the confirmation beep and see connectivity on the meter when the door is completely latched shut. If you get a constant closed circuit or no beep/signal at all regardless of position, the contacts inside the switch have likely failed. Time to replace it!

How to Replace a Faulty Door Switch

Start by fully unplugging the dryer from the wall outlet. Then flip up the top panel to better access the mounting screws. Remove the wires from the old door switch terminals and unscrew it from the frame. Install the new switch in the same location and connect the original wires to the matching colored terminals.

Close the dryer door and test that continuity now only registers when latched. If needed, adjust the alignment so the internal switch lever makes solid contact. Once operation is confirmed, button the protective cover panels back into place and reconnect power before running a test cycle.

Verifying Proper Door Switch Function

• Continuity (beep) only when door fully shut
• No continuity (no sound) when door is open
• Adjust positioning if needed
• Test cycle to confirm normal operation

Examining the Start Button

The next component in the electrical sequence is the start button or switch mounted in the dryer's control console. If the door safety mechanisms check out, problems here could be keeping the dryer from activating. Begin by popping off the button cover and disconnecting the wires. Establish continuity by touching the meter probes to the two switch terminals.

Press and hold the button down while watching for conductivity. Just as with the door switch, you should only get continuity when the button is fully depressed. If the meter beeps all the time or never beeps at all, the contacts inside the switch have likely oxidized or failed.

Replacing a Faulty Start Switch

After confirming the original start switch is faulty through testing, order an exact replacement part. When it arrives, remove power again from the dryer before removing the console cover panel. Take out the screws securing the bad start switch and disconnect the wires. Attach the wires to the same colored terminals on the new switch.

Mount the replacement switch with the original screws and press it multiple times while testing with your meter. If satisfied with the on/off operation, button the console cover back up and restore power. Verify normal functionality by starting a test cycle.

Key Start Switch Checks

• Continuity only when pressed
• Replace if constantly open or closed
• Use exact replacement part
• Confirm operation before reassembly

Testing the Motor

If your dryer won't start even after confirming the door switch and start button are operational, it's time to check the motor windings and associated capacitors. Unlatch the front panel or remove the rear cover to access these components. Locate the motor mounted to the back of the tumbler chamber.

Set your multimeter to the Ohms setting for testing conductivity across motor windings. Touch the probes to two different motor contact points at a time and note resistance values. Compare your readings across the possible contact pairs to what the factory service manual specifies.

Checking Run and Start Windings

Motors have both run and start windings that engage to spin the drum. Test continuity across these paths separately. If readings are way out of spec or you see no conductivity, the motor likely needs professional service or replacement. Values can shift over time with wear.

Also examine the attached capacitors for signs of damage like bulging tops or leaking fluid. Use the capacitor test mode on your meter if available to confirm microfarad values match rating labels. Faulty capacitors can prevent motor start-up or running.

When to Replace a Bad Motor

• Winding resistance far from factory spec
• Open windings with zero conductivity
• Shorted windings with very low resistance
• Failed or leaking start/run capacitors
• Over ten years old

Troubleshooting Control Board Issues

Many modern dryers also rely on an electronic control board to regulate operation. If the basics check out, failures here can mimic a no-start condition. Begin by removing the control console panel to visually inspect the board.

Look for signs of overheating like discolored or burnt spots on the circuitry. Also examine wire terminals for broken or loose connections. Use your multimeter to check key input and output voltages against service documentation.

Control Board Voltage Checks

• 120v feed from terminal block
• Neutral and hot feeds to heating circuits
• Low voltage signal wires
• Board ground connection

Replacing a Faulty Control Board

If voltages are missing or out of range and the board shows physical damage, a replacement will be necessary. Note wire positions, unplug all connectors, and remove mounting screws before installing the new board.

Consult default setting documentation and recheck key voltages during initial power up. You may need to program cycles and options lost during replacement. Test operation with a load at varying settings before considering repair complete.

Verifying Thermal Fuse Continuity

Another safety device existing dryers rely on that could cause a perceived no-start is the thermal fuse. This specialized fuse is wired in series to interrupt heating element power if temperatures inside the cabinet grow dangerously high due to restrictions in airflow.

Use your wiring diagram to locate the thermal fuse, typically mounted to the blower housing. Check continuity across its terminals just as with normal switches and components using your ohmmeter. No conductivity means the fragile fuse element has likely blown.

Why Thermal Fuses Fail Prematurely

• Blocked airflow and overheating
• Repeated cycling with very small loads
• Physically damaged during servicing
• Exceeded recommended operational life

Replacing a Faulty Thermal Fuse

Start by ordering a replacement fuse that matches the rating specifications of your dryer. Unclip the bad fuse and disconnect the wiring before installing the new one in the same location. Use wire nuts and electrical tape to isolate connections.

Test continuity across the repair before buttoning back up the machine. Clear any airflow restrictions and replace the vent ducting if notably damaged or extremely lint-clogged. Run an empty air fluff cycle before returning to normal operation.

Confirming Proper Belt Tension

If all checks so far have come back normal, also inspect the condition of the drive belt that transfers tumbler rotation from the motor. Over time belts can become loose, damaged from objects getting trapped, or simply wear out from age.

Removing cabinet panels will allow visual examination of belt routing through the pulley system. Check for cracking, glazing, fraying, or other deterioration. Press firmly midway between pulleys to gauge flexibility and tension.

Adjusting Belt Tension

If tension feels inadequate, locate the motor mount bolts and use wrenches to shift its position relative to the pulley assembly. Test rotation by spinning the tumbler manually once adjustments are complete. Proper tension should allow rotation without slipping but not overly bind.

When to Replace a Dryer Belt

• Missing sections or unraveling
• No longer flexible due to glazing
• Belt stretching from age or wear
• Squeaking, slipping rotation

Verifying Exhaust System Operation

The final area impacting dryer operation worth checking over is the external vent exhaust system. Lint buildup or blockages here can trigger the high limit thermostat to interrupt heating circuit power to prevent fires.

Detach the flexible vent hose at the rear of the machine and inspect inside with a flashlight for packed lint restricting airflow. Also confirm the flapper valve on the exterior vent hood opens and closes properly in response.

Clearing Lint Blockages

Use a vacuum crevice tool inserted down the vent hose to extract built-up lint from inside the chute leading outside. Check the entire run of solid ducting for obstructions as well. Replace any sections crushed or damaged.

With ducting reconnected, perform an empty air cycle and feel for good airflow output at the exterior vent hood. If airflow seems weak, have ducts professionally cleaned or replaced prior to further use to prevent strain and overheating.

Re-testing Dryer Operation

With all repairs and component replacements complete, restore power to the dryer and run it through a full operational test. Start by selecting a normal cycle and confirming the drum begins turning in response to start button activation. Use your senses and a thermometer to validate the machine heats properly in this mode.

Next, cancel this cycle and begin a timed air fluff sequence to gauge airflow strength down the ducting. Feel output at the exterior vent hood to make sure no restrictions remain. Finally, process a test load with weight representative of a normal drying session and allow the cycle to complete.

Post-Repair Testing Objectives

• Starts reliably via control panel
• Achieves operating temperature
• Maintains unrestricted airflow
• Runs full cycle without issues

Preventative Maintenance

Now that you're confident in having revived your dryer back to life, let's review key preventative maintenance steps to maximize operational longevity moving forward:

• Clean lint traps before every load - This simple habit minimizes fire risk and improves airflow.
• Periodically vacuum the vent ducting - Removes accumulated lint keeping exhaust clear.
• Confirm exterior vent hood moves freely - Ensure flapper can fully open and close as needed.
• Wipe down sensors and controls - Prevents dust buildup from impacting electronics.
• Check all connections are tight - Stops vibration from loosening wiring contacts over time.

Staying on top of maintenance goes a long way towards preventing repeat failures down the road. Be aware of any warning symbols or changing behaviors signaling service needs. Address issues promptly before operational disruptions occur.

Returning life to a dryer that won't start first requires methodical checks of key systems to narrow down root causes. Begin with power supply, move to sensors and switches, then inspect drive components and electronics.

Test components using a multimeter to determine if continuity is compromised. Replace switches, control boards, thermal fuses and motors exhibiting notable failures or wear. Also ensure proper venting to prevent overheating issues.

Many no-start problems can be solved with some basic electrical testing skills and safety knowledge. When issues escalate beyond your confidence level, however, don't hesitate to call in a professional appliance repair technician.