Rheem Rheem Performance 40 Gal. 4500-Watt 6-Year Tank Electric Water Heater RUMBLING Error Fix: Rumbling, Popping, or Banging Noises

Error code RUMBLING on the Rheem Rheem Performance 40 Gal. 4500-Watt 6-Year Tank Electric Water Heater means: Rumbling, Popping, or Banging Noises. Loud popping, rumbling, crackling, or banging sounds during heating cycles. This is caused by sediment accumulation at the bottom of the tank. The lower heating element sits in or near the sediment layer. When the element heats, water trapped beneath the sediment turns to steam, and the steam bubbles rise through the sediment, creating the noise (similar to a boiling kettle). While not immediately dangerous, heavy sediment buildup: (1) Reduces heating efficiency — the element must heat through the sediment before heating the water. (2) Shortens tank life — concentrated heat under sediment can weaken the tank bottom. (3) Can clog the drain valve, making flushing difficult. Drain and flush the tank. If the tank has not been flushed in many years, the drain valve may clog with chunks of sediment. In severe cases, replacing the drain valve with a full-port ball valve or removing an element to manually scoop sediment may be necessary.

The most successful fix is "Remove and Replace the Drain Valve to Clear Compacted Sediment" (medium difficulty, ~60 minutes). Estimated DIY cost: $15-$30. HomeMD has 2 community-ranked fixes for this error.

This error is rated info severity. It is generally not urgent and can often be resolved with a simple DIY fix.

Yes — the top-ranked community fix ("Remove and Replace the Drain Valve to Clear Compacted Sediment") is rated medium difficulty and takes about 60 minutes. Tools needed: Adjustable wrench, Plumber’s snake, Wire brush, Teflon plumber’s tape.

DIY cost: $15-$30. Professional repair typically costs $150-$250. Many homeowners save money by trying the top-ranked community fix first.

The Rheem Rheem Performance 40 Gal. 4500-Watt 6-Year Tank Electric Water Heater has 5 other known error codes, including: ECO TRIPPING (High-Limit Reset Button Keeps Tripping), ELEMENT SCALE (Heating Element Scale and Sediment Buildup), INSUFFICIENT HOT (Runs Out of Hot Water Too Quickly), LEAKING (Water Heater Leaking), NO HOT WATER (No Hot Water — Complete Failure).

Error code RUMBLING also appears on 1 other Rheem model: Rheem Professional Classic 50 Gal. 38,000 BTU Natural Gas Water Heater. The fix may vary by model, so check each model's specific page for tailored repair steps.