How to Troubleshoot a Whirlpool Dryer That Won't Heat

WhirlpoolWhirlpool DryerModerate⏱ 1 - 3 hours

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If a Whirlpool dryer tumbles but won’t heat, the problem is usually a missing leg of the 240 V supply, a burned terminal block connection, a failed heater or safety sensor, restricted airflow from lint buildup, or worn timer heat contacts. This guide walks you through safe checks and multimeter tests for the heater circuit, thermostats (including the cycling or operating thermostat), the thermal cutoff (also called a high-limit thermal fuse), and the timer.

🧰 Tools

Multimeter
1/4 inch nut driver
Large Needle Nose Pliers
Putty Knife
Heat Gun
Flush Cutter
Wire Stripper
Small parts container

⚙️ Parts

Terminal block
Dryer power cord
Heating Element
Thermal cutoff
Heater thermostat
Cycling thermostat
Dryer timer
Wire splice connector

ШагиSteps

Prepare safely and gather tools

WARNING: Turn off the dryer’s breaker and unplug the power cord before opening any panels.
If you need live voltage readings, keep hands clear of metal parts, use insulated meter probes, and avoid touching the terminals.
Set up a multimeter for AC voltage, continuity, and resistance (ohms) testing.
Gather a 1/4 inch nut driver, and keep pliers nearby for stubborn spade connectors.
Have a small container ready to hold screws as you remove them.

Inspect the terminal block and confirm the 240 V supply

Locate the terminal block where the power cord enters the back of the dryer, and remove the cover if your model has one.
Inspect the terminal block and cord for melting, charring, cracked insulation, or loose connections.
Replace the terminal block or power cord immediately if you see damage.
Set the multimeter to AC voltage, and measure from the middle terminal to the left terminal for about 120 V.
Measure from the middle terminal to the right terminal for about 120 V.
Measure between the left and right terminals for a total of 208–240 V.
If the left-to-right reading is below 208 V, cycle the breaker fully off and back on, and troubleshoot the breaker, outlet, or cord before continuing.

Remove the back panel

Use a 1/4 inch nut driver to remove all screws securing the back panel.
Remove eight to 10 screws, depending on whether the dryer has a steam port.
If the dryer has a steam port, remove the plastic cap and the additional screws around the port area.
Lift off the back panel and set it aside.

Identify the heater and airflow components

Find the heating system on the right side of the dryer’s rear opening.
Locate the thermal cutoff or high-limit thermal fuse near the top of the heater housing, and the heater thermostat and heating element near the bottom.
Find the blower housing on the left side, along with the thermal fuse and the cycling or operating thermostat that controls heat cycling.
Use the wire colors as a cue on the cycling thermostat: larger prongs often use red wires, and smaller prongs often use purple wires.

Test the heating element and inspect wiring

Pull off one spade connector from the heating element to prevent false readings.
Use pliers to remove the spade connector if it’s too tight to pull by hand.
Set the multimeter to ohms or continuity, and measure across the heating element’s two terminals.
A good element typically reads about 9–10 Ω, and an open or wildly high reading indicates a bad element.
Check for a grounded heater by setting the meter to continuity and measuring from an element terminal to the element’s metal casing.
Replace the heating element if the meter beeps or shows a reading from a terminal to the casing, because the heater is shorted to ground and is dangerous.
Inspect every wire terminal and spade connector for burn marks, and repair any burned wire by cutting away blackened sections and splicing with a heavy-gauge connector and a wire nut.

Test the thermal cutoff or high limit thermostat

Pull off one wire from the thermal cutoff or high-limit thermostat on the heater housing.
Set the multimeter to continuity or ohms, and test across the thermal cutoff terminals for a beep or near 0 Ω.
Replace the thermal cutoff if it reads open (no beep or OL), because it will prevent any heat.
Treat a failed thermal cutoff as a sign of overheating, often caused by lint buildup or a restricted vent.
Replace the thermal cutoff with the matching heater-side thermostat as a set to avoid repeat failures.

Clean airflow areas and test the cycling thermostat

Clean lint from the dryer interior, the blower housing area, and the vent path to reduce overheating and repeat fuse failures.
Pull off one red wire from the cycling or operating thermostat on the blower housing.
Set the multimeter to continuity or ohms, and test between the exposed thermostat spade and the other red-wire thermostat spade for continuity or near 0 Ω.
Pull off one purple wire from the smaller prongs, set the meter to ohms, and measure the small-prong pair for about 5,000–10,000 Ω.
Replace the cycling thermostat if the readings are vastly out of spec, because it can cause low-heat problems or overheating.
If thermal cutoffs keep blowing, heat-test the cycling thermostat with a heat source and watch for it to open around 155 °F by showing OL on the meter.

Test the timer heat contacts and reassemble

Use a 1/4 inch nut driver to remove the screws holding the metal console backing to expose the timer and switches.
Release the console by sliding a putty knife between the console housing and dryer housing, pressing hard on the spring clips, and pivoting the console up and out.
Remove the two bottom wire harnesses from the timer, and disconnect additional timer wires if needed to fully free the console.
Locate the timer’s four labeled connectors (A, B, C, and H), and set the dial to a high-heat mode around 70 minutes or any setting that avoids cooldown.
Set the multimeter to continuity, and test for continuity between A–B and A–C to verify the timer can feed heat.
Replace the timer, or temporarily clean its contacts, if you get no continuity or usable resistance on the heat contacts.
Turn the timer dial clockwise only, because turning it the other way can jam the gears or contacts.
Reconnect all timer harnesses, hook the console into place, snap the spring clips in, reinstall the console backing, reinstall the back panel, and restore power.

If the dryer heats normally after you correct the failed part or supply issue, finish the repair by cleaning lint from the airflow path and confirming strong venting to prevent repeat overheating failures. If the supply voltage, heater circuit, thermostats, and timer all check out, the remaining problem is likely in the wiring or a less common control issue. Repair didn't go as planned? Ask our Answers community for help.

«How to Troubleshoot a Whirlpool Dryer That Won't Heat» — автор Ben Schlichter, iFixit, лицензия CC BY-NC-SA 3.0. Показано без изменений. Открыть оригинал и комментарии →