Frigidaire Dishwasher Thermostat Replacement

This part is not a temperature control. Normal wash and dry temperatures are managed by the NTC thermistor and the control board — the hi-limit is a last line of defense that opens the heater circuit only in a runaway overheat. Understanding that distinction matters, because a tripped hi-limit is a symptom of another failure, not usually the disease itself.

How the disc works#

The bi-metal disc bonds two metals that expand at different rates. At its trip point of 180-200°F, depending on model, the disc snaps from closed — current flowing to the heater — to open, cutting heater power. Most Frigidaire models use a single-use, non-resettable disc: once it trips it stays open. A few use a resettable type that closes again after it cools, but if a resettable disc keeps tripping, the underlying cause has to be found rather than simply reset each time.

Where it lives#

The disc mounts near the heating element under the tub floor, reached by removing the bottom kick panel — usually two Phillips screws plus a pair of spring clips. It is a small disc, about 1 inch across, held by a single screw or clip with two wires attached to its terminals.

Symptoms — and why they mimic a dead element#

The reason a bad thermostat is so often mistaken for a bad element is that both produce the same headline complaint — no heat. The only reliable way to tell them apart is a meter.

Testing and replacing#

1. Kill power at the breaker and pull the kick panel.
2. Find the disc near the element terminals on the tub floor.
3. Disconnect one wire and set a multimeter to continuity.
4. At room temperature a good disc shows continuity, meaning closed; no continuity means it has tripped — replace it.
5. While you are in there, check the heating element too, since about 15 to 30 ohms is normal, and the two parts often fail together.

To swap the disc, photograph the wiring first, remove the mounting screw or clip, and seat the new disc with full contact against the tub so it can sense temperature accurately. A disc that is not flat against the metal reads late and can nuisance-trip. Reconnect both wires, refit the kick panel, and run a heated-dry cycle to confirm the element heats without tripping. Tools are simple: a number two Phillips, a multimeter, and often a 1/4-inch nut driver.

Find the root cause first#

A disc trips because something overheated the water. Common culprits are a failed NTC thermistor reporting a falsely low temperature, a heater relay welded closed on the control board, or restricted airflow trapping heat in the tub. Replace the thermostat without addressing that cause and the new disc may trip again within a few cycles. If the element is older than 8 years and you already have the panel off, replacing it alongside the thermostat is cheap insurance against a second teardown.

Your Frigidaire dishwasher is likely a same-day fix. EasyBear serves Sacramento and the Bay Area — schedule your repair.