Girard Tankless RV Water Heater Troubleshooting [A Complete Guide]

The most common Girard tankless RV water heater problems include:

  • The heater won’t turn on.
  • No hot water or water isn’t getting enough.
  • Too hot water.
  • The heater won’t ignite. 
  • Water is leaking at various points.
  • Or, the heater keeps shutting off.

Also while operating, Girard users encounter several error codes on the control display, indicating several malfunctions going through the heater. 

Anyway, whenever you’re encountering any of the problems above, you just need to identify the root cause of the specific issue first. Then head to the fixing procedures. 

Continue reading our extensive Girard RV tankless water heater troubleshooting guide to the end to break down each of the problems efficiently.

girard tankless rv water heater troubleshooting

Girard Tankless RV Water Heater Troubleshooting [7 Easy Solutions]

Here are the details of all major Girard Tankless RV Water Heater problems, explained with the corresponding reasons and quick solutions. Let’s start:

01. Girard Tankless Water Heater Not Turning On

If your Girard tankless water won’t turn on, degradation in the power supply is the first reason to blame here. Best chances are the circuit breaker has tripped or the fuse of the heater has blown. Also, there might be a problem with the wiring or power outlet. Your heater might be going through a loose connection or a non-operation wall outlet.

Another issue could be from the fuel source. As your Girard tankless water heater is gas-operated, it will require a good amount of fuel supply to ignite. In case, the heater unit is running out of sufficient fuel, it will not respond as it should.

How To Fix:

Here is all how you will deal with your Girard Tankless water heater no power issue:

First up, you need to check whether the power source is off. Look for tripped circuit breakers from the main electrical panel of your house. Reset the tripped breaker to get back your heater to normal operation. Also, remove the obstructions that are causing the breaker to trip. 

Now remove the front panel of your tankless water heater and you will find a dedicated fuse for your unit. 

girard tankless water heater fuse

You need to replace the fuse if it has blown. Plus, you will find a small on/off switch just above the fuse. Make sure it is turned on. 

Then, check the wiring to see if there are any loose or corroded connections. Tighten any loose wiring connection or replace the worn-out wires.

Now, check if the gas supply is connected to your water heater. For this instance, make sure that the gas valve is turned on and there is sufficient gas pressure. Look for any obstructions to the flow of gas and remove them. 

02. No Hot Water Or Water Is Not Getting Hot Enough

Nothing is more annoying than you’re ready to use your Girard tankless water heater and it is running out of hot water or the water temperature isn’t hot enough.

 In fact, this is the most common problem that users encounter with the tankless unit. For instance, setting the template too low is the leading reason to blame. 

Also, every RV tankless water heater has a limit switch to keep the unit temperature at the appropriate level.  It is a safety feature designed to protect against accidental scalding. Now in case the high limit switch is tripping, it will stop the heating function. 

Other most obvious reasons for this issue include:

  • Interruption in the power supply
  • The gas valve isn’t fully open
  • Sediment buildup 
  • Running too many appliances at once.
  • High water flow.
  • Loose or worn-out wiring
  • Blocked vents and air intake channels

How To Fix:

Here are the few effective steps that you need to follow to fix your Girard tankless water heater not heating issue:

Step #1: Start by checking the temperature setting whether it is set to the recommended level. Then, verify the power supply to your water heater. Make sure the circuit breaker is not tripped or the unit fuse is in well-working condition. Fix the loose wiring as well.

Step #2: When done, reset the unit by flipping the circuit breaker to the Off position once and then flip it back to the ON position. Also, turn off two more faucets that are stretching your tankless heater to its limit. 

Step #3: Now check if there is a flow restrictor in the hot water line as it will limit the heaters’ ability to reach a comfortable water temperature. For instance, remove the restrictor and purge air out from all the hot and cold water lines.

Step #4: Check the water flow rate on your heater through a flow regulator.   If the flow rate is more than 1 GPM on your heater, higher chance are you have a bad water flow sensor, replace the bad sensor.

Step #5: Check the vents and air intake channels of your hater for blockages. Make sure all are free of blockages, dust, or other debris. Plugged-up burners are also a major source of problems. Thus, make sure they’re clean!

Step #6: Still, there is no hot water, so I recommend heading to a technician for further troubleshooting.

03. Too Hot Water

If the water coming from your Girard tankless water heater is too hot than the maximum temperature you’ve set, be sure it is an alarming sign for which you need troubleshooting action right now. 

The first would be the improper thermostat setting. If you are setting the inlet temperature over approximately 90 degrees, the water heater will fail to regulate the output temperature correctly.

In case, the temperature is not at an appropriate level, there may be any of the following reasons:

  • A restriction or malfunction in the outlet or inlet valve
  • Blocked air supply
  • Clogged or cracked heat exchanger 

How To Fix An Overheated Girard Tankless Water Heater

Here are the quick fixes to diminish the too-hot water issue from your Girard RV tankless water heater:

First off, make sure your tankless water heater’s thermostat is not set at a high level. It will be better to set the temperature at around 120 F or 49 degrees C. Also, ensure that your thermostat is in well working condition.

thermostat of girard tankless water heater

Clean out all the restrictions from the inlet and outlet valves. Then inspect the venting system of your tankless unit to see if something blocks the air supply.

If that is so, the burner will run hotter than usual and trigger overheating. Clean out the air blockages from the vents and the air inlet screen.

If still the problem persists, be sure the source of the problem might be hard water that has plugged up the heat exchanger. So, what’s the solution? Flush your water heater to get it back into normal functions. If you want, you can contact a professional for further discussion.   

04. Girard Tankless Water Heater Leaking

It is a quite common phenomenon that you are using your RV tankless water heater and suddenly water starts coming out from the bottom. The problem is more likely related to the loose water line connection to your water heater. 

Other major reasons include improper venting, scale buildup through the heater elements, and high water pressure. 

How To Fix:

There are a variety of ways to fix & prevent an RV tankless water heater from leaking. Go through the following effective ones:

i. Secure The Fittings

First off, make sure that all of the water lines and fittings are tight and secure. Use a wrench to tighten the fittings. If you find any holes in the hoses, apply a little duct tape to cover the holes. You need to replace the worn-out gasket or O-ring. 

ii. Check The Venting

Your RV tankless water heater needs proper venting to keep it away from leaking. Try to concentrate on this fact while using the heater! 

iii. Flush Your Water Heater 

Hard water is one of the leading reasons for tankless water heater leaks. To prevent your tankless water heater from leaking due to hard water, you need to flush your water heater. 

iv. Decrease The Water Pressure 

In case, the leakage is caused by high water pressure, reducing the water flow from the pressure relief valve. The RV water flow should be between 1 and 1.4 Gallons per Minute to ensure the optimal operation of the water heater.

Also, remember that a steady water flow is key to maintaining a consistent temperature and performance. 

05. Girard Tankless Water Heater Won’t Light

If your Girard RV tankless water heater is not igniting, be sure there are some major malfunctions in the fuel supply to your water heater. Either there is not sufficient gas pressure or there is a leak in your fuel system. Or, there may be something that is blocking the flow of gas. 

At times, scale build-up on the heater elements is the leading reason behind the Girard tankless water heater, not lighting issues. Especially, if there is condensation or debris on the burners, it will easily cause them not to ignite.

Also, low water pressure is one of the frequent causes of this issue. Other reasons would be faulty power issues of the control board due to loose electrical wiring or a blown fuse.

How To Fix:

Start troubleshooting by checking the gas valve connection of your water heater. Make sure the gas valve is open. Plus, check you have paid all the bills for your gas connection.

 Then look for obstructions in the gas line for your water heater. Remove the obstructions and if needed purge the air from the gas line to ensure a fluent fuel supply.

After that, inspect the control panel to see if the wirings are not corroded or loose. Replace the blown fuse. Then measure the water pressure for your tankless water heater using a pressure regulator. 

pressure regulator

Ensure the heater is getting its required maximum water flow. If not, increase the water flow by opening the water valve up all the way.

If still, the problem persists, be sure it is time to inspect the burner. To do so effectively, head to our detailed guide on Girard tankless water heater won’t light issue.  

06. Girard Tankless Water Heater Keeps Shutting Off

If your RV tankless water heater is failing to stay on, be sure your heater is going through a major malfunction on the power supply. Simply there would be loose or corroded wiring connection to the control board or the source of the problem might be a non-working power outlet. 

Besides, all the RV tankless water heater including the Girard model equips a high-limit switch that is designed to protect the heater against accidental scalding. 

Now in case you are reducing the water flow too low, it causes a higher temperature (122°F) that triggers the safety switch and shuts off the unit.

Most of the time, it happens due to the failure of many of the heater components or blockage in the air vents of the system.

How To Fix:

There is nothing to worry about. Go through the below quick fixes to troubleshoot the constant shut-off problem of your RV tankless system. 

Step #1: First off, ensure that your water heater is getting a fluent electric supply to stay on. For instance, look for worn-out wires and fix them. If there is a circuit breaker issue, you need to reset the breaker.

Step #2: Then if you suspect low water flow going through your water heater, you need to increase the water pressure right now. You can do it either from the water control valve, located on the rear of the water heater or simply by lowering the water temperature.

Step #3:  Above all, monitor all the air vents and inter-filter screens of your water heater. You have to make sure that there’s no debris in them. Don’t get a hassle if you’re wondering about how to clean the air blockage in your RV tankless system.

I’ve compiled the effective procedures to do so in our comprehensive Girard tankless water heater keeps shutting off troubleshooting guide. Just take a look at our guide and make your task easier.

07. Girard Tankless Water Heater Error Codes

While operating the tankless water heater, it’s quite common that you will encounter that the unit shuts off and the display shows an error code. It will basically be a diagnostic error code indicating an unsafe condition of the system, detected by the controller module.

Now in the case of the Girard Tankless Water Heater, there are also a  few common error codes you may encounter while using the heater. 

Here is the comprehensive list of all the Girard tankless water heater error codes with their error indication and quick solutions:

Error Code Error Indication Quick Solutions 
E0Water outlet temperature probe failure # Verify the resistance of the probe with a voltmeter.
# If the outlet probe isn’t an open circuit or short, replace it. 
E1Ignition failure # Check for low inlet gas pressure.
# Inspect the connections between the igniter and burner. # Clean out the accumulated dirt or obstruction from the igniter and burner.
E2Flame sensing interruptions during normal operation Go through all the troubleshoots for the E1. Additionally, replace the flame sensor if the buzzer sounds. 
E3The ECO thermostat opens during or before the ignition. Restart the unit to get back it to normal temperature. 
E4Water inlet temperature probe failure# Check for faulty connection to the probe.
# Replace the worn-out one. 
E5Blower motor failure Clean the blockage in the air supply or in the exhaust system. Replace the faulty blower motor. 
E6Excessive temperature Restart your tankless water heater. 
E7 Linear valve failureReplace the faulty valve. 
E8Cut-off air pressure switch during normal operation or before ignition A system timer indicating the heater has run longer than 20 minutes. 
E9Flame sensor failure Look for a short in the flame sensor. Replace it if needed. 
EndA system timer indicating the heater has run longer than 20 mins. No action is required.
FdUsing water heater operating in winter use mode # Turn off the main power switch at the water heater while 12V power is ON. 
# Remove the flow restrictor from the faucets and the shower.

How To Reset Girard Tankless Water Heater

If your RV tankless water is not working properly as it should, resetting is one of the best effective solutions in such cases to minimize the appearing issue. It will help to set the heater into the default setting. 

In the case of the Girard tankless water heater, you may not get a built-in reset button to make your resetting process far easier.

Yet, there is an ECO valve switch that tends to trip at various points due to the rising temperature like 140°(F). In that case, the button gets popped in and shuts down the unit to protect it from overheating-related damages.

When this happens, you just need to press the button and it will pop back in. Track down the reset button location from the below picture. 

reset button of girard tankless water heater

You can also reset the unit through the hot water faucets. To learn how to do so, go through an in-depth discussion on this fact from our detailed Girard tankless water heater reset button guide.

Girard Tankless Water Heater Maintenance

There is no doubt to say that a Girard tankless water heater offers an energy-efficient way to get hot water on demand. But to ensure a long service life and optimal performance of the heater, the system requires effective maintenance by the users at least once a month.

Go through the below simple steps to maintain your RV tankless water heater. Also, I recommend taking a look at our in-depth guide on Girard tankless water heater maintenance.

01. Flush Your Tankless Water Heater

While operating it is quite obvious that your water heater comes into constant contact with hard water. It causes scale build to the heat exchanger that reduces its efficiency. 

As a solution, you’ve to descale and flush your water heater at least once a year. It will remove the build-up of lime and calcium deposits inside the tankless system. 

02. Clean The Inlet Air Filter

Unlike other RV tankless models, the Girard tankless water heater features an air inlet filter that can easily get clogged with dirt, insects, and other debris. You need to clean this filter screen to ensure a fluent air flow to the heater

03. Inspect The Air Inlet Openings

Along with the air filter screen, check all the air inlet openings. Verify that they are completely open and free of any obstructions to allow full airflow.

04. Inspect The Interior Surface 

Inspect the internal combustible materials, specifically the burner and the gas controls for any cracks or damages. If needed, replace the damaged parts.

05. Examine All The Wiring Connections

Above all, don’t miss checking all wire connections regularly. Here is the Girard tankless water heater manual, from where you can track down the wiring diagram for your RV water heater. 

With the help of the diagram, verify all the wires are properly connected to the control board and there is no sign of cracks on the insulation. 

Besides the damaged part replacement, you should service your tankless water heater by a professional technician at least once every year to catch any potential issues in the system before it becomes more serious. 


How do you turn on a Girard tankless water heater?

First off, push down the “ON” button on the control plane and it will light up. Then turn on the hot water faucet and after a few seconds the water will start heating.

How do I adjust the temperature on my tankless water heater?

After turning on the control display, you will see a temperature of 115 °C degrees at the default setting. Then, press the “UP” or “Down” and adjust the temperatures between 95 degrees to 125 degrees.  

What is the LED indicator on the controlled display of the Girard tankless water heater?

The red indicator signs no operation of the heater when the voltage is below 10VDC. When the voltage turns to 17VDC, the green LED lights up. Then the Amber LED lights up, indicating normal operation.

What to do if there is no operation at the UCP of Girard GSWH-2 tankless water heater?

If there is no power at the UCP but present at the control board, be sure you’ve faulty wiring between the UCP and the control. In case, both UCP and the board have no power, then the control board is bad and needs quick replacement. 

How to replace the flow meter on Girard tankless water heater?

First off, remove the set screw and loose compression fittings of the flow meter. Then twist the flow meter without damaging the O ring. When done, reinstall the new flow meter back in place.  

In Closing!

Whenever there are any major issues in your tankless water, inspect the control board and ensure it is getting proper power. Check all the wiring for any loose and corroded connections on the board. In most cases, the failing control board is the only responsive factor that needs replacement.

If still the problem persists, you will need a deep inspection of the system corresponding to the problem. That’s the point our detailed Girard RV tankless water heater troubleshooting guide is enough to prove well.  

I have highlighted all the most common issues that Girard users often face with their effective solution. Let us know how our complete discussion reaches you. We really feel glad to find our readers in the comment section.

Well, before leaving you can take a look at our complete troubleshooting guide on Bosch tankless water heater (for both gas & electric) if you have this water heater.

Good Luck!

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