Reliance electric tanks use industry-standard screw-in elements interchangeable with State, AO Smith, Whirlpool, and most other major brands. Standard residential is 4500W upper + 4500W lower at 240V.
Element specs by Reliance model
| Model | Element | Mounting |
|---|---|---|
| 6-30-EORS (30-gal) | 4500W upper + lower | Screw-in 1-1/16" |
| 6-40-EORS (40-gal) | 4500W upper + lower | Screw-in 1-1/16" |
| 6-50-EORS (50-gal) | 4500W upper + lower | Screw-in 1-1/16" |
| 6-66-EORS (66-gal) | 4500W upper + lower | Screw-in 1-1/16" |
| 6-80-EORS (80-gal) | 4500W or 5500W upper + lower | Screw-in 1-1/16" |
| 9-50-EORS (50-gal 9-yr) | 4500W upper + lower | Screw-in 1-1/16" |
| SOMS 6-gal / 10-gal mini-tank | 1500W single | Screw-in (smaller) |
| HPHE-50 / HPHE-66 (resistance backup) | 4500W upper + lower | Screw-in 1-1/16" |
Testing the element
See our Reliance element resistance test guide. Quick reference: 4500W healthy reads 10-16 Ω; open = failed; continuity to tank shell = shorted.
High-watt density vs low-watt density
- High-watt density (HWD): shorter element, more heat per square inch. Faster recovery, but scales faster in hard water. Factory default on most Reliance units
- Low-watt density (LWD): longer element, more surface area, less localized heat. Lasts much longer in hard water
If you\'ve had multiple element failures in hard water, switch to low-watt density on the next replacement. About $5 more per element.
Replacement procedure
- Power off at the breaker; verify with voltage tester
- Drain the tank — full drain for lower element; ½-drain for upper
- Remove access cover and insulation
- Disconnect wires (note positions)
- Unscrew element with 1-1/16" element wrench
- Install new element with new gasket (always replace the gasket)
- Refill tank — open a hot tap upstairs to vent air. Wait for steady stream
- Restore power only after the tank is fully full
Critical: never power up dry
A dry-fired element burns out in seconds. Always confirm the tank is full before flipping the breaker. Hot tap should run steady with no air sputter.
Cost
- 4500W standard element: $20-35
- 4500W low-watt density: $25-40
- 5500W element: $25-40
- 1500W mini-tank element: $20-30
- Element wrench (1-1/16"): $10-15 — reusable
- Plumber labor: $100-180 if hired
Bottom line
Reliance elements are universal — buy from any source. Low-watt density is the upgrade for hard water. Never power up a dry tank.