A reliable hot water supply makes the difference between a comfortable RV trip and a frustrating one. Whether you're washing dishes at the campsite or taking a hot shower after a long day of hiking, your RV water heater is one of those systems you don't think about — until it stops working.

The good news is that RV water heaters are relatively simple systems, and most problems can be prevented with regular maintenance. Here's everything you need to know to keep yours running reliably.

Types of RV Water Heaters

Before diving into maintenance and troubleshooting, it helps to know what type of water heater you have.

Tank-Style Water Heaters (Suburban and Atwood/Dometic)

The most common type in RVs. These hold 6 or 10 gallons of water and heat it using propane, electric, or both. Suburban and Atwood (now Dometic) are the two dominant brands. They're reliable, easy to service, and parts are widely available.

Tankless (On-Demand) Water Heaters

Increasingly common in newer RVs. These heat water on demand rather than maintaining a tank of hot water. They're more energy-efficient and provide unlimited hot water, but they're more complex and more expensive to repair.

Combo Units

Some RVs use a combination unit that serves as both a water heater and a space heater. These are more complex and require specialized service.

Annual Maintenance: What to Do Every Year

Consistent annual maintenance prevents most water heater problems. Here's what to do at the start of each camping season.

Flush and Clean the Tank

Sediment and mineral deposits build up in the tank over time, reducing efficiency and shortening the heater's life. At the start of each season:

1. Turn off the water heater and let it cool completely
2. Turn off the water supply and open a hot water faucet to relieve pressure
3. Remove the anode rod (if equipped) or the drain plug
4. Let the tank drain completely
5. Use a tank rinse wand to flush out sediment
6. Inspect the anode rod — replace it if it's more than 50% depleted

The anode rod is critical. It's a sacrificial magnesium rod that protects the steel tank from corrosion. If you skip replacing it, the tank itself will corrode. A new anode rod costs about $10–$15. A new water heater costs $300–$600+.

Inspect the Burner Assembly

For propane water heaters, inspect the burner tube and orifice for spider webs, dirt, or debris. Spiders love to build nests in propane orifices during storage — a blocked orifice is one of the most common causes of ignition failure.

Use compressed air to blow out the burner tube. If the orifice is clogged, use a fine wire or orifice cleaning tool to clear it — never use a drill bit, which can enlarge the orifice and affect the flame.

Check the Pressure Relief Valve

The T&P (temperature and pressure) relief valve is a safety device that releases pressure if the tank overheats or over-pressurizes. Test it annually by lifting the lever briefly — you should hear water or steam release. If it doesn't release or if it leaks after testing, replace it immediately.

A failed T&P valve is a safety hazard. Don't skip this test.

Inspect the Exterior Door and Vent

Check the exterior access door for damage, proper sealing, and clear ventilation. The vent must be unobstructed for safe propane combustion. Look for wasp nests, debris, or damage to the door seal.

Common Water Heater Problems and Solutions

Water Heater Won't Ignite (Propane Mode)

This is the most common complaint. If the water heater clicks but won't light:

Check the propane supply. Is the tank valve open? Is there propane in the tank? Try lighting another propane appliance (stove burner) to verify gas flow.

Check for a blocked orifice. As mentioned above, spider webs and debris in the burner orifice are a very common cause of ignition failure. Clean the orifice and burner tube.

Check the igniter. The igniter electrode should have a gap of about 1/8 inch from the burner. If it's corroded, cracked, or misaligned, it won't produce a reliable spark. Clean or replace it.

Check the gas valve. If the gas valve isn't opening, the burner won't get fuel. This requires professional diagnosis.

Water Heater Won't Heat on Electric Mode

Check the breaker. The electric heating element is on a dedicated circuit. Check the breaker panel for a tripped breaker.

Check the element. Electric heating elements burn out over time. Test with a multimeter — a good element will show continuity. A burned-out element reads open (no continuity) and needs replacement.

Check the ECO (Energy Cut-Off) switch. The ECO is a thermal fuse that trips if the water heater overheats. It's a one-time safety device — once it trips, it must be replaced. It's located on the back of the water heater and looks like a small button or disc.

Water Is Lukewarm, Not Hot

If you're getting warm water but not hot water:

• On propane: the burner may be running at reduced output due to a partially blocked orifice or low gas pressure
• On electric: the heating element may be partially failed or the thermostat may be set too low
• On both: the thermostat may need adjustment or replacement

Water Heater Leaks

Pressure relief valve leaking: If the T&P valve drips continuously, it may be faulty or the system pressure may be too high. Replace the valve if it's leaking after testing.

Drain plug or anode rod leaking: Tighten the plug or rod. If it continues to leak, the threads may be damaged — use Teflon tape and retighten, or replace the plug.

Tank leaking: A leaking tank usually means corrosion has eaten through the steel. This is not repairable — the water heater needs to be replaced.

Fitting or connection leaking: Check all water connections at the inlet and outlet. Tighten fittings or replace if the threads are damaged.

Rotten Egg Smell from Hot Water

A sulfur or rotten egg smell from hot water is caused by a reaction between the magnesium anode rod and certain water supplies. The fix is to replace the magnesium anode rod with an aluminum/zinc anode rod, which doesn't produce the same reaction.

Winterizing Your RV Water Heater

If you store your RV in North Texas winters, proper winterization protects your water heater from freeze damage.

1. Turn off the water heater and let it cool
2. Drain the tank completely by removing the drain plug or anode rod
3. Leave the drain plug out during storage to allow any remaining moisture to escape
4. Bypass the water heater when winterizing the plumbing system (use the bypass valves if equipped)

Never use antifreeze in the water heater tank — it's difficult to flush out completely and can affect taste.

Repair vs. Replace: Making the Decision

Most water heater components are replaceable — igniter, thermostat, heating element, anode rod, T&P valve. If the tank itself is leaking or severely corroded, replacement is the only option.

A new 6-gallon tank-style water heater runs $300–$450 for the unit, plus labor. If your water heater is more than 10 years old and needs multiple repairs, replacement often makes more financial sense than continuing to repair it.

Mobile Water Heater Service in North Texas

Done Right RV Repair provides mobile water heater diagnosis, maintenance, and repair throughout the DFW Metroplex. Our RVTI Master Certified technician comes to your location with the parts and tools to handle most water heater repairs on the first visit.

We serve Granbury, Fort Worth, Weatherford, Burleson, Cleburne, and 50+ cities across North Texas. Call us or request service online — we'll come to you.