Water Heaters Parts, Service Kit

Rheem SP21219 – Titanium Upper Element for Marathon Series Water Heaters

The Rheem SP21219 upper heating element is an OEM-grade replacement part engineered specifically for use in Rheem Marathon electric water heaters. Constructed with a titanium sheath for maximum corrosion resistance, this 240V, 4500W low-watt-density element is designed to maintain optimal heating performance in challenging water conditions including high mineral content or aggressive chemistry.

Designed for Demanding Applications

This element is manufactured to Rheem’s production-line specifications and is supplied as an original component in Marathon water heater assemblies. It features a fused terminal for dry-fire protection and is intended for upper position replacement only. It is not interchangeable with standard copper or nickel-chromium elements due to its unique design and material compatibility requirements with polybutene tanks.

Key Features

• Titanium Sheath: Engineered for high-durability performance in aggressive water chemistry environments where standard elements may corrode prematurely
• OEM Certified: Matches factory specifications for all Rheem Marathon units using 4500W upper elements
• Fused Terminal Safety: Built-in dry-fire fuse disconnects the circuit if the element is energized without submersion
• Low Watt Density: Distributes heat evenly over a larger surface area, reducing scaling and improving efficiency
• Threaded Mount with Gasket: 1” NPSM thread with rubber gasket included for secure, leak-resistant installation

Technical Specifications

• Voltage: 240V AC
• Power Rating: 4500 Watts
• Element Type: Screw-in, titanium
• Mount Thread: 1” NPSM
• Density: Low watt density
• Application: Upper position only in Rheem Marathon electric water heaters

Installation Considerations

While the SP21219 element is designed for direct replacement, professional installation is strongly recommended. Proper torque must be applied to prevent gasket leaks, and electrical safety procedures must be followed. Dry-firing voids the element’s functional integrity; confirm the tank is completely full before restoring power.

For Mechanical Contractors and Field Technicians

Stocking the SP21219 ensures fast turnaround on element failures in residential and light commercial electric water heaters. Its non-reactive titanium build eliminates common premature failures caused by electrolysis and hard water conditions. As a genuine Rheem part, it supports factory warranty coverage and system integrity.