1. Place a 3/8”
wooden dowel
rod into center of
thermostat then
place in 85°F water.
Make a reference
mark on the rod as
shown in fig. A.
2. Now insert
thermostat into hot
water that is at least
20°F higher than
the set temperature
stamped on label.
3. The rod should
move out of
the thermostat
approximately 1/8”.
If the rod shows no
movement or can
be pushed inward,
a new thermostat is
required.
Figure A
Reference
Marks
3/8” Wooden
Dowel
Thermostat
Figure B
1
19
2
18
21
Testing the Thermostat
