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Pentair

Pentair 474989 MasterTemp 125 Thermal Regulator

Pentair 474989 MasterTemp 125 Thermal Regulator

$55.99 USD
$55.99 USD
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The Pentair 474989 Thermal Regulator controls water temperature within the Pentair MasterTemp heater system. If your MasterTemp 125 rapidly cycles between the heating and the service mode, the thermal regulator is likely the component that needs inspecting. 

Who is this for?

Mastertemp heater owners troubleshooting their pool heater, tend to buy this regulator as a fast fix for knocking sounds. Many service techs note that the bypass valve tends to fail around the same time, so it be worth it to replace both. 

*Always confirm the model of your product for compatibility before ordering any part. Please call Shasta Pool Supply if you are not sure and we will be happy to help.*

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Key Features

  • Regulates water flow through the heat exchanger alongside the internal bypass valve
  • Maintains correct outlet water temperature to prevent heat exchanger overheating
  • Listed as item 12 in Pentair's MasterTemp 125 water system parts diagram
  • Common replacement when a heater short cycles or knocks during operation
  • Newer bronze header revisions add a stainless sleeve for better wear resistance

Technical Specifications

  • Component: Thermal Regulator
  • Heater compatibility: Pentair MasterTemp 125
  • Parts diagram position: Item 12, water system
  • Works with: Internal bypass valve, manifold assembly

Specs

Pro Tip: Pentair 474989 MasterTemp 125 Thermal Regulator

Replace the thermal regulator if your MasterTemp 125 shows signs of inconsistent heating, and inspect related water-system components during service. It is recommended to have a licensed professional install this part. The 474972 manifold kit and 474974 union kit cover the rest of a full MasterTemp 125 water system rebuild.

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Fast ship, salt cell was vital to get replaced! Thank you

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Works great. Fast shipping

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Very good service and I will be back, thanks Chuck

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