Pentair
Pentair Probe Thermistor Defrost Sensor
Best replacement part for pool heat pump owners needing freeze protection.
Ensure your Pentair pool or spa heater operates efficiently and safely with the Pentair Probe Thermistor Defrost Sensor (473665). This genuine replacement part is vital for managing the defrost cycle, preventing freeze damage to your heating system. It's specifically designed for compatibility with Pentair UltraTemp Heat Pump, UltraTemp ETi Hybrid Heaters, and ThermalFlo Heat Pump Titanium models. Trust this essential component for reliable temperature regulation and optimal heater performance, especially during colder conditions.
$54.95
Owner Satisfaction
4.5
/ 5
Category Rank
446
/ 2960
#446 in Pool & Spa Accessories
Price vs Category Average
-83%
Below average
Manufacturer Part Number
473665
Who it's for
- Pool owners requiring precise temperature control for efficient heating
- Homeowners looking to extend the lifespan of expensive heat pumps
- DIYers needing a guaranteed fit for existing Pentair systems
Who should skip it
- Users in harsh climates prone to frequent sensor corrosion
- Budget-conscious buyers seeking affordable generic replacement parts
- Novice owners lacking advanced diagnostic tools or technical expertise
Performance breakdown
OEM Compatibility
Perfectly engineered to match original Pentair heat pump specifications.
Freeze Protection
Critical sensor accuracy prevents costly ice damage during winter months.
Installation Simplicity
Straightforward plug-and-play design makes for a quick, hassle-free replacement.
Thermal Precision
Maintains consistent temperature readings for reliable defrost cycle activation.
Build Durability
Robust construction withstands harsh, moisture-heavy pool equipment environments.
System Reliability
Essential component for keeping high-end heaters running through cold snaps.
Key Specs
Manufacturer Part Number
473665
Compatibility
UltraTemp Heat Pump, UltraTemp ETi Hybrid Heaters, ThermalFlo Heat Pump Titanium
Product Type
Probe Thermistor Defrost Sensor
Pool Type Compatibility
In Ground
Features
- Protects heater from freeze damage
- Genuine Pentair replacement part
- Ensures proper defrost operation
- Maintains heater temperature regulation
- Compatible with UltraTemp and ThermalFlo heaters
- Essential for reliable heater function
What customers say
This Pentair replacement thermistor sensor is overwhelmingly praised as an essential, highly effective part for pool heaters and heat pumps. Customers value the straightforward plug and play installation, which allows for easy DIY replacement and immediate cost savings. The sensor reliably resolves critical system errors, especially those involving defrost cycles or incorrect temperature readings, quickly restoring full functionality. While most users report perfect compatibility and immediate reliable performance, a small number of reviews mention concerns about long term durability compared to the original part. Overall, the consensus confirms this component offers exceptional value and is a highly recommended, necessary purchase for maintaining system reliability.
Know before you buy
This sensor monitors the temperature of the heat pump's evaporator coil to determine when a defrost cycle is necessary. By managing this cycle, it prevents ice buildup and protects the internal components from freeze damage.
Common signs of a faulty sensor include the heat pump failing to initiate a defrost cycle, excessive ice accumulation on the coils, or the heater displaying a specific error code related to the thermistor. If your unit is not heating properly in colder weather, testing the sensor is a logical first step.
No, this specific sensor is designed exclusively for the UltraTemp Heat Pump, UltraTemp ETi Hybrid Heaters, and ThermalFlo Heat Pump Titanium models. Always verify your heater's model number before purchasing to ensure compatibility.
Yes, the 473665 is an original equipment manufacturer (OEM) part produced by Pentair. Using genuine parts ensures the sensor meets the exact calibration and durability standards required for your specific heater model.
While the installation is straightforward for those comfortable with basic pool equipment maintenance, it involves accessing the internal electrical components of the heat pump. If you are not familiar with high-voltage equipment, it is recommended to have a qualified pool technician perform the replacement to ensure safety and proper calibration.
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