How to Troubleshoot a Frigidaire Dryer That Won't Heat

ID: 207215

Description: [youtubevideo|7JhJtb015QI]Use this guide to...

Steps:

Unplug the dryer and pull it forward so the rear terminal-block cover is accessible.
Remove the single Phillips screw and lift off the small metal cover to expose the block.
Inspect the cord and block for burned or blackened spots that would inhibit heating.
Set the multimeter to AC volts and read from center to left and center to right; each should show about 120 V.
Measure left to right and confirm 208–240 V AC; low or missing voltage means an external electrical problem.
Take out the two Phillips screws at the rear of the top panel, slide the panel back, and lift it off the cabinet.
Locate and save the folded technician’s sheet found under the top for schematic reference later.
Disconnect the dryer from the wall outlet before continuing any disassembly.
Remove the two screws securing the user interface to the bulkhead and pull it forward slightly.
Photograph the connector layout, then unplug the interface harness and set the interface aside.
Take out the two screws holding the control board cross-plate so the board can be shifted later.
Open the door and remove the two long Phillips screws securing the lint-filter housing to the inner bulkhead.
Close the door and remove the two lower front-panel screws found slightly inboard of each bottom corner.
Remove the two upper screws; support the panel as it loosens so it does not drop.
Lift the panel forward, unplug the door-switch harness, and place the panel out of the work area.
Unplug the door-light harness from the control board to clear the bulkhead.
Take out the two lower screws securing the bulkhead, then lift the bulkhead up to unhook it from its side tabs.
Use needle-nose pliers to pinch and release the cable tie that anchors the door-switch wire to the bulkhead.
Set the bulkhead aside or lean it safely against the cabinet.
Wear gloves and long sleeves to protect against sharp internal sheet-metal edges.
Reach behind the blower housing, pull the idler pulley to the left to slacken the belt, and slip the belt off the motor shaft.
Grasp the belt and lift the drum straight out of the cabinet, noting which rim faces the rear rollers.
Inspect the lint-filter chute and blower area for packed debris that can block airflow.
Vacuum or hand-remove any buildup until the passage is clear and the flexible hose stays unclogged.
Pull the two wires off the black thermistor mounted on the blower housing.
Set the multimeter to resistance in the 20–200 kΩ range.
Measure across the terminals; 50-55 kΩ at room temperature indicates a healthy thermistor.
Replace the thermistor if the reading is far outside this band or the meter displays OL.
Detach the two wires from the outlet thermal fuse located on the vent pipe.
With the meter on resistance or continuity, probe the fuse; a good fuse reads near 0 Ω.
An OL reading means the fuse is open and must be replaced before reassembly.
Remove the wires from the rear-mounted thermostat on the heating canister and measure resistance; it should be near 0 Ω.
Perform the same test on the mid-canister thermal fuse; it also must read near 0 Ω.
Replace both parts and clean the exhaust path if either fuse is open to prevent repeat overheating.
Label and remove every wire from the heating element terminals.
On three-plus-one elements, check from the right power post to each left post; 25-30 Ω is normal.
On two-wire elements, measure between the two posts; about 10 Ω is expected.
Probe from any post to the metal canister; any reading other than OL indicates a grounded coil that requires replacement.
Note wire colors, then remove the two screws anchoring each canister foot to the cabinet.
If fitted, remove the small rear screw holding the canister to the bulkhead with a stubby screwdriver or angled wrench.
Transfer the thermostat, thermal fuse, and mounting legs to the new canister using their original screws.
Seat the new canister so its feet drop into the chassis slots and reinstall the mounting screws firmly.
Reconnect all wires fully and secure excess slack with a high-temperature cable tie, avoiding bends in spade connectors.
Verify the idler pulley spring is attached and the belt ribs face the drum surface.
Lower the drum into the cabinet so its rear rim rides between the back rollers.
Pull the idler pulley left, loop the belt around the motor pulley, then release tension to tighten the belt.
Rotate the drum by hand to confirm smooth movement and proper belt tracking over the motor and idler pulleys.
Hang the front bulkhead on its four side tabs, rotate the drum if needed, and install the two lower bulkhead screws.
Snap the door-switch harness back into the bulkhead and reconnect it to the control board.
Lift the front panel into place, plug in the door-switch connector, and seat the panel on its chassis tabs.
Secure the panel with the two top screws, the two bottom screws, and the two long filter-housing screws inside the door.
Plug the interface harness into the original board socket, matching your reference photo.
Snap the interface tabs into the front and secure it with its two screws.
Slide the top panel forward into position and reinstall the two rear retaining screws.
Remove the board cover and look for burned relays, scorched traces, or cracked solder joints.
Replace the board if physical damage is evident or if earlier tests found no voltage reaching the element.
Reconnect all board wiring, leave the board loose, and keep hands clear of metal before restoring power.
Using the schematic, place one meter lead on the black line at the terminal block and the other on board pins J52, J71, or J73 while the dryer runs.
A reading above 200 V AC confirms the board is energizing the element circuit; low or zero voltage means the board is faulty.
Unplug the dryer again before reinstalling the board and cross-plate screws.

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