There is nothing quite like jumping into the shower after a long day of hiking only to realize your rv water heater ignitor isn't clicking, leaving you with a face full of ice-cold water. It's one of those minor mechanical failures that can totally derail the mood of a camping trip. One minute you're enjoying the sunset, and the next, you're standing outside in your pajamas with a flashlight, staring at a metal box and wondering why it won't just light up.
If you've spent any significant amount of time living the RV life, you know that hot water is a luxury we often take for granted until it's gone. Most modern RV water heaters are DSI (Direct Spark Ignition), meaning they use an electronic ignitor to kickstart the flame. When that little component decides to call it quits, or even just gets a bit dirty, your comfort levels drop significantly. Let's talk about how these things work, why they fail, and what you can do to get that hot water flowing again.
Understanding That Clicking Sound
When you flip the switch inside your rig, you should hear a faint clicking sound coming from the heater's exterior vent. That's the rv water heater ignitor doing its job. It sends a high-voltage spark across a small gap—very similar to a spark plug in a car—to ignite the propane gas.
If you hear the clicking but the flame doesn't catch, the ignitor might be working fine, but the gas isn't reaching it. If you hear absolutely nothing, you're likely looking at a power issue or a dead ignitor assembly. It's a simple system, but because it's exposed to the elements, things can get messy pretty quickly. Road dust, moisture, and even tiny critters can mess with the electrical path.
Why Do These Ignitors Fail?
The most common enemy of an rv water heater ignitor isn't actually mechanical failure; it's usually Mother Nature. For some reason, spiders absolutely love the smell of propane. They tend to crawl into the burner tube and spin webs. These webs can deflect the gas flow or physically block the ignitor's spark from reaching the gas. It sounds ridiculous, but a single spider web can be the difference between a hot shower and a cold sponge bath.
Rust and corrosion are also big players. Since the water heater vent is open to the outside, humidity and rain eventually cause the metal electrodes to oxidize. If there's a layer of rust on the tip of the ignitor, the spark won't be strong enough to jump the gap.
Then there's the issue of the "gap" itself. Over time, through heat cycles and vibration from driving down bumpy backroads, the metal probes can shift. If they are too far apart, the spark can't jump. If they are too close, the spark is too weak. It's a Goldilocks situation—it has to be just right.
Troubleshooting the Basics
Before you go out and buy a replacement rv water heater ignitor, there are a few things you should check. First, make sure you actually have propane. I know it sounds silly, but I've seen people pull their heaters apart only to realize their tanks were bone dry. Turn on your stove burners to see if you have a steady blue flame. If the stove works, you've got gas.
Next, check your battery voltage. A DSI water heater needs a solid 12 volts to create that spark. If your house batteries are low, the ignitor might click weakly or not at all. If you're plugged into shore power, this usually isn't an issue, but it's always worth a look at your monitor panel.
If the power and gas are good, head outside and open the water heater access panel. Look at the wires leading to the ignitor. These are often thin and can become brittle or vibrate loose. Give them a gentle wiggle to make sure they are seated firmly on the control board. If a wire is frayed or the insulation is cracked, the spark might be "leaking" out and grounding against the frame before it ever reaches the burner.
Cleaning and Maintenance
If the rv water heater ignitor looks intact but isn't firing, a little cleaning might save you $30 and a trip to the parts store. Use a piece of fine-grit sandpaper or a small wire brush to gently scrub the tips of the electrodes. You want to see shiny metal. Be careful not to bend them too much while you're at it.
While you're in there, take a can of compressed air or a soft brush and clean out the burner tube. Getting rid of those spider webs or any accumulated soot can make a huge difference. Sometimes the ignitor is sparking perfectly, but the gas is being diverted away from it because of a blockage.
After cleaning, check the gap. Generally, you're looking for about an eighth of an inch (roughly the thickness of two pennies) between the electrodes. If it looks wider than that, you can very carefully bend it back into place. Just don't force it; the ceramic insulation around the base of the ignitor is brittle and will snap if you put too much pressure on it.
When to Replace the Ignitor
Sometimes, no amount of cleaning will bring an rv water heater ignitor back to life. If the ceramic casing is cracked, the electricity will take the path of least resistance and jump through the crack to the metal frame instead of at the tip. At that point, it's toast.
The good news is that replacing an rv water heater ignitor is a pretty straightforward DIY job. Most of them are held in by one or two screws and a single high-tension wire. You just unscrew the old one, disconnect the wire from the control board, and reverse the process with the new part.
When buying a replacement, make sure you get the specific model for your heater brand—usually Atwood (now Dometic) or Suburban. They look similar, but the mounting brackets and electrode lengths are often different. It's worth taking the old one with you to the store or double-checking the model number on the water heater tank itself.
Pro Tip: Don't Forget the Control Board
If you've replaced the rv water heater ignitor and you still aren't getting a spark, the problem might be further upstream. The control board is the "brain" that tells the ignitor when to fire. These boards are notorious for failing, especially if they get damp.
You can usually tell if a board is bad by looking for scorched spots or a "burnt electronics" smell. If the board isn't sending power to the ignitor, no amount of fiddling with the electrodes will fix it. There are some great aftermarket boards, like those from Dinosaur Electronics, that are built a bit tougher than the stock ones and handle the vibrations of the road a lot better.
Final Thoughts on Keeping the Heat On
Dealing with an rv water heater ignitor issue is just part of the "adventure" of owning a camper. It's one of those things that usually breaks at the most inconvenient time—like 10:00 PM on a Friday night in a remote campground.
The best advice I can give is to keep a small wire brush and a screwdriver in your "emergency" tool kit. Most of the time, a quick cleaning is all it takes to get things back in order. And if you're a full-timer or someone who travels frequently, it's not a bad idea to keep a spare ignitor in your parts bin. They're small, relatively cheap, and can save your vacation when the hot water suddenly decides to take a vacation of its own.
Just remember to turn off the power and the gas before you start poking around in there. Safety first, hot showers second. Once you get that steady roar of the burner going again, you'll realize just how much you appreciate that little spark. Happy camping, and may your showers always be warm!