Comstock Castle 17039 is a Bjwa Thermostat. It senses temperature and cycles the heating or cooling circuit to hold the set point. Replacement is usually called for when you are seeing temperatures that overshoot or undershoot the dial, or a unit that runs continuously or not at all.

It also cross-references 2 manufacturer part numbers. Check the number on the part you are replacing, or your unit's model number, against the lists below before ordering.

Supplied as a single replacement unit.

T'stat - Bjwa Temp LO-200-400-HI Bulb 3/16" X 8" Cap 36" Gas Out 1/4" FPT, "C" Rear Rotation 0 Degrees Body Down With 3/8" Cct X 1/4" MPT 90 Brass Elbow Thermostat Kit Now Includes Knob, Bezel, Flange And Elbow Comstock Castle Griddle.

Cross-reference

• Comstock Castle: 17037-A, 17039

Ordering by part number is the most reliable way to get the right part.