Tankless RV Water Heater Repair & Service
Furrion. Girard. GE. All brands serviced. Certified technicians since 1993.
Your Tankless Water Heater Is Not Working the Way You Expected
Maybe you are not getting hot water at all. Maybe the temperature swings between hot and cold. Maybe it worked fine for a year and now it throws an error code every time you turn it on.
Tankless RV water heaters are great when they work correctly. Endless hot water, no tank to fill, less propane wasted keeping water hot when you are not using it. But they require a different approach than the tank-style heater you may be used to, and they need annual maintenance that many owners do not know about.
Before you assume something is broken, there are a few things you should understand about how your tankless unit is designed to work.
How to Use Your Tankless Water Heater Correctly
The number one complaint we hear about tankless water heaters is temperature fluctuation. Hot, then cold, then hot again. Almost every time, the problem is not the unit. It is how it is being used.
Set the temperature where you want it. Let it get there. Use it.
Do not set the heater to a high temperature and then add cold water at the faucet to cool it down. When you mix in cold water, you reduce the flow rate through the heater. The unit senses the reduced flow, cycles off, and then cycles back on when flow increases. You end up chasing the temperature back and forth and never getting consistent hot water.
This is not a malfunction. This is how every tankless water heater works. Set it to the temperature you actually want, let the unit reach that temperature, and use the hot side only.
Will it be instant? No. It will be quickly hot, but not instant. The water sitting in the line between the heater and your faucet has cooled off. Once that clears, your hot water is continuous for as long as you need it.
If you are using the unit correctly and still experiencing temperature problems, then it is time for a technician to look at the flow sensor, gas valve, or control board.
Annual Descaling Is Not Optional
Every tankless water heater builds up mineral scale and deposits over time. This is true regardless of brand. Scale reduces heating efficiency, restricts water flow, and eventually causes component failures.
The descaling process involves connecting a circulation pump and running a vinegar solution through the unit for about one hour. It is a straightforward service, but it does require a specific process to do correctly.
Most tankless owners do not know this maintenance exists. If your unit has never been descaled and you have owned it for more than a year, schedule a cleaning before you end up with a more expensive repair.
Annual descaling is the single best thing you can do to extend the life of your tankless water heater.
Winter Use and Freeze Protection
Tankless water heaters are vulnerable to freeze damage. Unlike a tank-style heater that holds a volume of water with some thermal mass, a tankless unit has small passages that can freeze and crack quickly when temperatures drop below freezing.
If you plan to use your RV in below-freezing temperatures, you have two options:
Winter-Use Device
Some tankless units have a winterization device or heating element designed to keep the unit from freezing during operation in cold weather. Check whether your specific model offers this and make sure it is installed and functioning before cold weather arrives.
Purge and Bypass
If your unit does not have a winter-use device, you need to purge the water from the heater with antifreeze and bypass it. You can continue using your RV, but the tankless heater needs to be taken out of the water system until temperatures are safely above freezing.
Freeze damage is one of the most common and most expensive tankless water heater failures we see. A few minutes of preparation before cold weather can save you a replacement.
Maintainable Brands vs. Disposable Brands
The tankless RV water heater market is being flooded with knockoff brands that undercut the established manufacturers on price. The problem is that most of these brands do not offer replacement parts. When they fail, they cannot be repaired. They also come with limited door size options, which means finding one that fits the existing hole in your RV can be a challenge.
We call them disposable vs. maintainable.
Maintainable Brands
These manufacturers offer replacement parts, have established service networks, and build units that are designed to be repaired. When something fails, we can fix it.
Furrion, Girard, GE
Disposable Brands
These units do not have parts available for repair. When they fail, the only option is replacement. They also often have limited door size options for your RV's existing cutout.
Fogatti*, RecPro*, and various off-brand units
*No replacement parts available from manufacturer
Our recommendation: We always recommend replacing a failed unit with a maintainable brand. Longevity is what we hope to offer our guests. A unit you can service and repair for years is a better investment than a cheaper unit you throw away when it breaks.
That said, if a disposable brand comes in broken and you need a quick replacement, we keep disposable units in stock for a direct swap. The specific brand we carry changes from time to time due to the nature of the market. Either way, we will get you back in hot water.
Common Tankless Water Heater Problems We Fix
No Hot Water
Unit does not fire at all. Common causes include a failed gas valve, bad igniter, tripped flow sensor, or low water pressure. We diagnose the specific failure rather than guessing at parts.
Error Codes
Modern tankless units display error codes when something fails. Each brand uses different codes. We have the diagnostic references for Furrion, Girard, GE, and others to trace the code back to the specific component that needs attention.
Scale Buildup
Reduced flow, inconsistent heating, or longer wait times for hot water. These are signs of mineral scale inside the heat exchanger. Annual descaling prevents this, but if it has been neglected, we can clean and restore the unit.
Freeze Damage
Cracked heat exchanger or split fittings from water freezing inside the unit. This is often a replacement situation, not a repair. Prevention through proper winterization is far less expensive than the repair.
Flow Sensor Failure
The flow sensor tells the unit when water is moving and triggers ignition. A failed or dirty flow sensor means the unit does not know you turned on the hot water. On maintainable brands, this is a straightforward parts replacement.
Igniter or Control Board
The igniter sparks to light the burner. The control board manages the entire heating sequence. When either fails, the unit will not produce hot water. We test and diagnose before replacing to make sure you are not paying for a part you do not need.
Frequently Asked Questions
Why does my tankless RV water heater fluctuate between hot and cold?
This is the most common complaint we hear, and almost every time it is not a malfunction. Set the temperature to your desired level and leave it there. Do not set it high and then add cold water at the faucet. Mixing cold water changes the flow rate, which causes the unit to cycle on and off. Set the temp you want, let it get there, and use the hot side only.
How often does a tankless RV water heater need to be cleaned?
Once a year at minimum. The descaling process runs a vinegar solution through the unit with a circulation pump for about one hour. Scale buildup reduces efficiency and causes premature failures. If you have never had your tankless unit descaled, do not wait for a problem to show up.
What brands of tankless RV water heater do you service?
All of them. Furrion, Girard, GE, and every other brand on the market. For maintainable brands, we repair with genuine parts. For disposable brands like Fogatti and RecPro that do not offer parts, we can replace the unit. We always recommend upgrading to a maintainable brand for longevity.
Can I use my tankless RV water heater in freezing weather?
Only with proper precautions. You need either a winter-use device installed on the unit or you need to purge the water from the heater with antifreeze and bypass it. Freeze damage cracks heat exchangers and splits fittings. It is one of the most expensive failures we see on tankless units, and it is entirely preventable.
My tankless water heater is broken. Should I replace it with the same brand?
If your unit is a Furrion, Girard, or GE, repair is usually the better option since parts are available. If your unit is a Fogatti, RecPro, or similar off-brand, it cannot be repaired because no parts exist. We recommend replacing it with a maintainable brand. We do stock disposable units for a direct swap if that is your preference, but for longevity, a maintainable brand is the better investment.
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Certified technicians. Accurate diagnosis. Every brand serviced.