Raypak Heater Bulb Sensor Well | 007211F

Engineered as a direct OEM replacement, the Raypak 007211F is a stainless steel bulb sensor well — also referred to as a thermowell — that protects the temperature sensing bulb within the heat exchanger on a wide range of Raypak pool and spa heater models. The sensor well acts as a protective sleeve positioned between the temperature sensor and the pool water flowing through the heat exchanger, shielding the sensor from direct water contact and pressure while still allowing the bulb to read water temperature accurately for proper heater operation. The 007211F measures 3-3/8 inches in length with a 15/32-inch inside diameter and a flared 9/16-inch outside diameter at the open end, and its single-piece stainless steel construction is engineered for strong corrosion resistance and long-term thermal durability in demanding pool heater environments. Compatibility covers Raypak heater models 53, 53A, 53B, 55A, 151, 153, 153A, 155A, 181, 183A, 261, 263A, 331, 333A, 401, and 403A, and the 007211F was formerly listed under Raypak part number 350336. Highlights Single-Piece Stainless Steel Construction: Manufactured from a single piece of stainless steel to Raypak's exact OEM specifications, the 007211F sensor well delivers strong corrosion resistance and reliable thermal performance throughout the service life of compatible Raypak pool and spa heaters operating in chemically active environments. Shields the Temperature Sensing Bulb: The thermowell isolates the temperature sensing bulb from direct contact with pool or spa water flowing through the heat exchanger, protecting the sensor from water pressure, chemical exposure, and mechanical stress while still allowing the bulb to register water temperature accurately for the heater's control circuit. OEM Dimensional Match: With a 3-3/8 inch overall length, 15/32 inch inside diameter, and a flared 9/16 inch outside diameter at the open end, the 007211F replicates Raypak's original factory specifications precisely so the sensor well seats and seals correctly within the heat exchanger during installation or service. Compatibility Across the Raypak Legacy Lineup: Fits Raypak pool and spa heater models 53, 53A, 53B, 55A, 151, 153, 155A, 181, 183A, 261, 263A, 331, 333A, 401, and 403A, giving service technicians and homeowners one part number to cover thermowell replacements across a large slice of Raypak's historic heater product lineup. Supersedes Raypak Part Number 350336: The 007211F is the current Raypak OEM part number replacing the older 350336 designation, meaning anyone searching by either reference number will land on the same component and can be confident they are ordering the correct thermowell for their compatible heater model. Compatibility Compatible with most Raypak heaters, please refer to your owners manual to confirm compatibility