
Pentair Thermal Regulator for MasterTemp 125 Heater Water System, 474989
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Quick overview
- Genuine Pentair Factory part 474989 for the MasterTemp water system.
- Model 125 specific Sold for the MasterTemp Model 125, not the larger MasterTemp sizes.
- Water system part Fits into the heater water path where the original regulator sits.
- Direct replacement Goes in place of the existing regulator with no adaptation.
- Protects the heat exchanger The regulator manages heater water flow, which is what keeps the exchanger out of trouble.
- Match the model Pentair uses different regulators across the MasterTemp and Max-E-Therm range, so confirm yours is the 125.
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Thermal Regulator for MasterTemp 125 Heater Water System, 474989
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Product details
The Pentair 474989 is the thermal regulator for the MasterTemp Model 125 heater water system. It is the genuine Pentair replacement for the regulator fitted at the factory.
Where it sits
The regulator lives in the heater water path. It manages how water moves through the unit, which is what keeps the heat exchanger working within its design range instead of taking the full brunt of whatever the pump sends it.
Getting the right one
Pentair uses more than one regulator across the MasterTemp and Max-E-Therm families. This one is listed for the MasterTemp Model 125. Confirm the part number on the regulator you are pulling out before ordering, since the wrong size will not seat correctly.
| Brand | Pentair |
|---|---|
| Manufacturer part number | 474989 |
| UPC | 788379865252 |
| Type | Thermal regulator |
| Fits | Pentair MasterTemp Model 125 heater water system |
| Sold as | Single replacement regulator |
| Shipping weight | 0.75 lb |
| Ships | Parcel |
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Questions and answers
What people ask about this product, answered by our pool techs.
Which heater does this fit?
Will it fit a larger MasterTemp?
Is it a genuine Pentair part?
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