
Sta-Rite Thermistor for Max-E-Therm and MasterTemp Heater Electrical System, 42001-0053S
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Quick overview
- Genuine OEM The Sta-Rite factory thermistor, part 42001-0053S.
- Max-E-Therm SR-200, SR-333, SR-400 The thermistor listed across all three model sizes.
- MasterTemp as well It also belongs to the MasterTemp heater electrical system.
- Temperature sensing The thermistor is how the heater control reads water temperature.
- A common no heat cause A failed sensor can leave a heater refusing to fire, or displaying a temperature that does not match the pool.
- Direct replacement Swaps in for the original sensor with no change to the wiring.
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Thermistor for Max-E-Therm and MasterTemp Heater Electrical System, 42001-0053S
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Product details
Sta-Rite 42001-0053S is the replacement thermistor for the Max-E-Therm SR-200, SR-333 and SR-400 heaters. The same sensor is part of the MasterTemp heater electrical system.
What it does
The thermistor is the heater control board eyes on water temperature. Its resistance changes with temperature, the board reads that, and everything downstream follows: what the display shows, when the burner fires, when the heater satisfies the setpoint and shuts down.
When it is the problem
A drifting or failed thermistor makes the heater behave in ways that look like other faults. Temperatures that read nothing like the pool, a heater that will not fire even though the pool is cold, or short cycling near setpoint all point at the sensor. It is an inexpensive part to change and a common one to find at fault.
Fitting
It is a direct OEM replacement, so it goes back into the same location on the same wiring. Kill power at the breaker before opening the heater.
| Brand | Sta-Rite |
|---|---|
| Manufacturer part number | 42001-0053S |
| UPC | 022315209817 |
| Type | Thermistor |
| System | Heater electrical system |
| Fits | Sta-Rite Max-E-Therm SR-200, SR-333, SR-400 |
| Also fits | MasterTemp heater electrical system |
| Shipping weight | 0.1 lb |
| Ships | Parcel |
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Questions and answers
What people ask about this product, answered by our pool techs.
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