About 15 years ago, I bought a Grants electric frying
pan on eBay for $10. Recently, the knob of
the pan’s West Bend thermostat stopped turning.
Knowing that putting pliers to it would only break
the knob or strip the knurling, I opted instead to
disassemble the unit. The threaded shaft that the knob operated
had dried out and seized. Lubricating the threads with
Tri-Flow fixed the thermostat. The thermostat also has a neon
light that had stopped operating due to age. When I shined a
bright light on the failed neon lamp, it started working again
because the light preionizes some of the noble gases inside the
lamp. The lamp stopped working when I reassembled the unit
because it was mostly shielded from ambient light.
Prying off the metal label revealed a dreaded sight:
a snap ring designed only to go on, not come off
for service. I managed to pry the ring off with a
0.4×2×60-mm, flat-blade Stahlwille screwdriver.
A spring holds the knob against the body as the
central shaft moves in and out. I glued the label
back on with silicone aquarium cement.
1. A neon light with a series
dropping resistor is wired
across the two output
terminals so that the lamp
glows when the thermostat
closes and power travels to
the pan’s heating element.
2. A loop of wire over
one of the three screw
bosses serves as a wire-strain
relief. The bottom
cover has bumps that
clamp the wire when it
3. The knob seized because lack of lubrication caused
the threads in the metal frame to seize. To free up
the threads, I sprayed them with Tri-Flow spray
lubricant and carefully worked the knob back and
forth in small increments, using pliers when necessary.
When the threads were properly lubricated, I
could turn the knurled shaft with my fingers.
4. The steel tube that
inserts into the frying pan
has a bimetallic element
that operates the contact
points as it bends with
5. A bare braided wire allows
heat from the barrel contact
to dissipate before it reaches
the thermostat assembly.
6. Rotating the temperature knob
pushes the lower contact
leaf closer to or farther from
the bimetallic spring. When
the lower leaf is far from the
bimetallic spring, it must heat
up more to bend far enough to
open the contact points.
7. Applying a few spritzes of DeoxIT liquid
on the contacts cleans, protects, and
lubricates them when they engage the
pins on the frying pan. I found a business
card, from an honored competitor,
with a good abrasive texture and cut it
into strips that I ran between the contact
surfaces after I applied the DeoxIT.