Pentair Tub O-Ring Kit | MasterTemp & Max-E-Therm Heaters | 474952

Description

The Pentair Tub O-Ring Kit (474952) is the OEM replacement kit for MasterTemp and Max-E-Therm heaters equipped with the new 9-bolt lid tub design — manufactured after November 16, 2013.

⚠️ IMPORTANT: KIT CONTENTS — NOT A SINGLE PART
This listing is a complete kit. Each kit includes a O-Ring, nuts and washers — all three components required for a full heater service.

⚠️ IMPORTANT: POST-11/16/13 HEATERS ONLY — 9-BOLT LID TUB DESIGN
This kit fits MasterTemp and Max-E-Therm heaters manufactured after November 16, 2013 with the new 9-bolt lid tub design. Heaters built before this date use a different tub configuration and require a different kit. Verify your heater’s manufacture date before ordering.

⚠️ IMPORTANT: GAS HEATER COMPONENT — PROFESSIONAL SERVICE REQUIRED
Gas and electrical heater components must be serviced by a licensed pool professional or qualified HVAC technician. Do not attempt to service gas or high-voltage components without proper certification.

The tub O-ring seals the combustion chamber lid on MasterTemp and Max-E-Therm heaters, maintaining the pressure boundary between the combustion zone and the surrounding heater cabinet. A degraded or compromised O-ring can allow combustion gases to escape the chamber, reducing heater efficiency and creating a potential safety hazard. The included o-ring, nuts and washers complete the service, ensuring a full restoration of the heater seal. Match the manufacture date on your heater’s label to confirm the 9-bolt lid tub design before ordering.

Specifications

Fits Into

Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment’s manual or on the original part itself before ordering.

Pro Tip

Before ordering, locate your heater’s manufacture date label — typically found on the inside of the front door panel or on the rating plate. This kit is designed exclusively for the 9-bolt lid tub design introduced after November 16, 2013. Counting the bolts on your combustion chamber lid is a reliable field check: 9 bolts confirms this is the correct kit.