Use the following information to best determine which aquastat would be best for your needs.

P/N 169 - Adjustable Aquastat: Adjustable between 110-240 F, immersible with 1/2" MPT fittings on well (either close on rise or open on rise). Recommended operating setting is between 165-195F. 

P/N 204 - Adjustable Aquastat: for 1992 and older Classic outdoor wood furnaces, adjustable from 100-240F.

P/N 191 - Pool Aquastat: For controlling water temperature in pools, spas, etc. Immersible, temperature range of 40-180 F in one degree differential. With pool or hot tub application, it is recommended to use a stainless steel well (P/N 1248) sold seperately.

P/N 290 - Fixed Aquastat: Non adjustable, 175 F, immersible, 1/2" MPT fitting.

P/N 399 - Fixed Aquastat: Non adjustable, 190 F, immersible, 1/2" MPT fitting.

P/N 1247 - Well: 1/2" NPT fitting.

P/N 1248 - Well: Stainless Steel, 1/2" NPT fitting.