Rheem RTEX-24 — Water Heater
General Water Heater GuideQuick maintenance guide
Own this appliance? Track it free in HomeBaseQuick Specs
| Typical Tank Capacity | 40–80 gallons |
| Voltage (Electric) | 240 V |
| BTU Input (Gas) | 30,000–50,000 BTU/hr |
| Recovery Rate (Gas) | 35–45 GPH |
| Recommended Temperature | 120 °F |
Maintenance Schedule
| Task | How Often | Difficulty | Est. Time |
|---|---|---|---|
| Test the temperature and pressure relief (T&P) valve | Yearly | Easy | 5 minutes |
| Flush the tank to remove sediment | Yearly | Medium | 30–45 minutes |
| Inspect the anode rod | Every 2–3 years | Medium | 20 minutes |
| Check for leaks around fittings and valves | Every 6 months | Easy | 5 minutes |
| Verify temperature setting is at 120°F | Yearly | Easy | 2 minutes |
Troubleshooting
No hot water
Water not hot enough
Rumbling or popping noises
Water leaking from tank
Reset Procedures
Gas Water Heater Pilot Relight
- Turn the gas control knob to the OFF position.
- Wait 5 minutes for any residual gas to dissipate.
- Turn the knob to PILOT.
- Press and hold the knob while using the igniter or a long match to light the pilot.
- Continue holding for 30–60 seconds after the pilot lights.
- Release the knob and turn to the desired temperature setting.
Electric Water Heater Reset
- Turn off the circuit breaker for the water heater.
- Remove the access panel (usually upper panel).
- Press the red reset button on the thermostat.
- Replace the access panel and insulation.
- Turn the circuit breaker back on.
Safety Warnings
Setting the water heater above 120°F increases the risk of scalding burns. Higher temperatures are especially dangerous for children and elderly.
Call a professionalNever block the T&P relief valve discharge pipe. It is a critical safety device that prevents tank explosion from overpressure.
Call a professionalFor gas water heaters: if you smell gas near the unit, do not attempt to light the pilot. Leave the area and contact your gas company.
Call a professionalVideos
Rheem Tankless Water Heater Annual Maintenance Flush
Fix It Scotty
Rheem Tankless Electric Water Heater | NO HEAT? CHECK THIS FIRST!!
Project LS Audi A4
Rheem Rtex-18 Troubleshooting – Electric Tankless Problems & Fixes Guide
RM info TV
Don't miss this when you flush / descale a tankless water heater! 
The Meticulous Repair Tech
Rheem 24 KW Electric Tankless Water Heater Installation In Fort Myers, FL #plumber #plumbing #diy
Ultra Plumbing & Drain Cleaning
Rheem 36 KW Electric Tankless Water Heater Installation In Fort Myers, FL - Ultra Plumbing
Ultra Plumbing & Drain Cleaning
E5 Error on Rheem Tankless Water Heater
David in France
Rheem RTEX-24 24kW 240V Electric Tankless Water Heater - Review 2025
Lelia Rollins
Tankless electric water heater fully installed! #diy #homeflipping #construction
Matt Cadabra
Rheem RTEX-24 24kW 240V Electric Tankless Water Heater, Gray
Theil Elena
Rheem RTEX-13 Tankless Water Heater NO hot water resolved
Be Still
Rheem 27kW Flow Rate Electric Tankless Water Heater | Adjust Temperature Digital Display
Heating and Air Conditioning
HvacRepairGuy 2024 Rheem Electric Tankless Water Heater Reviews
hvacrepairguy
Cleaning the inside of a Rheem tankless water heater
cfldriven
Tankless Electric Water Heater Rheem repair
ROOF TECNOLOGÍA Y MÁS
How to fix flickering led lights caused by an electric tankless water heater
SS6-A
Rheem 240V 2 Heating Chambers RTEX-18 Residential Tankless Water Heater Review
Freshnss
Rheem RTEX-24 Electric Tankless Water Heater Review - Best Electric Tankless Water Heater
Birdie Ratke
HvacRepairGuy 2023 Rheem Electric Tankless Water Heater Reviews
hvacrepairguy
Rheem RTEX-24 Electric Tankless Water Heater Review - Best Electric Tankless Water Heater
quicK Review
Rheem 240V 3 Heating Chambers RTEX-24 Residential Tankless Water Heater Review
Freshnss
Best Electric Tankless Water Heater 2026 On Demand Hot Water
Consumer Sherpa
Rheem RTEX-24 24kW 240V Electric 2022
Reviews mixes
Rheem RETEX-18 The Review You Want To See
Preston 636
6699 tankless water heater Rheem flush
Brooks Cunningham
This guide contains general maintenance information for Water Heater appliances. For model-specific instructions, consult your owner's manual.
This guide is provided for informational purposes only. Always consult your official owner's manual before performing maintenance. HomeBase is not responsible for any damage resulting from the use of this information.
Related Guides
Never forget this task again
Track it free with HomeBase — automatic reminders, completion history, and cost tracking for all your home maintenance.
Start Tracking Free