How To Replace RV Water Heater With Tankless

How To Replace RV Water Heater With Tankless

Whether you have a recreational vehicle or modern home, the hot water is also an essential on-demand. So, you may want to consider a tankless water heater. What you have to do if one day, your model is broken. At that time, you need to learn how to replace the RV water heater with tankless. I will show you my detailed instruction below

How to replace RV water heater with tankless?

How to replace RV water heater with tankless
How to replace RV water heater with tankless

It’s simpler than what you think. You need to be patient and follow step by step. The outcome will satisfy you. However, you have to keep in mind the followings cautions to protect yourself away from any danger


Before performing, there are some notes you should remember:

  • You had better invest in the union connector sets for your water supply because it employs bypass capacity. This is a way to simplify your maintenance process in the future.
  • Your safety is one of the top priorities so you need to turn off the bigger diameter supply of the gas, high voltage power supply, and the main incoming water inline into a house.
  • While disconnecting the heat source from the old water heater for gas or propane, ensure to close the supply valve. You can check by determining whether or not the direction of the handle to the valve sitting and the line open are the same. For electric ones, you unplug your appliance from the wall outlet simply.
  • In spite of disconnection, it’s hard to avoid some water residue in the line so you should put a bucket underneath your water bid to deal with any spills.
  • After disconnecting and removing your old model, you have to dispose of it according to the laws in your country.

Step-by-step instruction

Take your new tankless water heater out of the box. Don’t forget to place all hardware and instructional material in your reach

Choose a right position for your appliance. The most important feature is that place must provide proper clearances around in accordance to all state as well as local building codes.

Before mounting the tankless heater on the wall, it’s essential and important to read the instruction from the manufacturer in advance to ensure you can support its weight appropriately.

After that, you hook up all the connections of the RV water heater with tankless

In case your model is a gas RV water heater with tankless, your choice should be a ventilation ducting because most tankless water heaters need a bigger or special stainless steel flue.

You had better start your replacing process in the supply line (water line) then move to the heat source. If your model runs with electricity, simply plug it into the wall. On the contrary, that is gas, it’s essential to hook up the gas supply line from the stub at the wall to your new model. Also, you need to adjust the direction of the value and the handle in the same line.

Check the manufacturer direction and follow what it guides. Perhaps, you are required to light the pilot on the gas water heater.

Everything is done now. What you have to do is to go to your bathroom and enjoy an endless stream.

How to repair a tankless water heater?

Rv Hot Water Heater Maintenance
Another way to avoid applying how to replace RV water heater with tankless

Repairing an RV water heater with tankless is always cheaper than replacing the whole new one. Thus, you need to check carefully to know whether or not that part can be repaired.

What you need

However, before going deeper into my instruction, you need to prepare the following things:

  • Phillips head screwdriver
  • Element wrench
  • Bucket
  • Battery-powered voltmeter
  • Rag
  • Hair dryer
  • Masking tape

My step-by-step instruction

Turn off the power

First of all, you have to disconnect the electrical power at the breaker box or control panel. To make sure no one connects the power back while you are performing the task, you should put a piece of masking tape over the switch. Use a voltmeter to check the circuit even when you can’t read anything that shows on the panel display. Without carefulness, you can cause danger to yourself even others.

Open hot water faucet

If you open a hot water faucet and turn off the water supply to the heater at the same time, perhaps some water will siphon out of the heater.

Drain heater

Use a Phillips head screwdriver to take off all 6 screws at the right bottom of the cleanout on the heating chamber plate’s underside. For the rest of water, you should drain them into a bucket. Finally, replace a new cleanout plate.

Remove wires

At the top of your heating element, there are red and black wires which are secured with screws. Your task is to remove all of them.

Remove old element

You can use an adjustable wrench to loosen the heating element. However, pay attention that you have to protect the control board away from water dripping by wrapping a rag around the heating element. Moreover, it’s essential and important to unplug your heating element along with the O-ring from the model.

Seat a new O-ring

Before installing the new one into your heater, you must ensure that there is a proper seal in your new heating element. And while performing, try to tighten the element as snugly as possible.

Replace wires

Use a Phillips head screwdriver to mount 2 screws for replacement of the red and black wires at the top of the element.

Turn on the water supply

Before turning on it, you must ensure that the drain plug screw is as tight as possible. Check carefully the water around your heater element to drain plug.

Dry control board

If the water drips into the control board, you can dry it by using a hairdryer as long as its behind is dry also. Do that in a certain time to ensure the whole one is completely dry without being harmed.

Fill up and heat

To know whether or not your model has any leak, the best way is to fill it with water. If everything is fine, you can turn the power switch on.

How to buy the best RV tankless water heater?

Buying the best model before learning how to replace RV water heater with tankless

If you try to maintain your model as well as possible but nothing is efficient, you have to learn how to replace RV water heater with tankless. And buying one is a must. Here, I will share with you a buyer’s guide for the tankless water heater with the important features:

Source of power

What is the specific source of power for your tankless water heater? There are 3 options for you: natural gas, propane, and electric. This depends on the single source of fuel in your RV or home. That means you should pick up a model which runs with your available power supply.

But, if you have more than one choice of fuel supply, you need to be careful with your option. For example, the gas models require your minimal maintenance while the electric tankless water heaters are pretty expensive. Thus, let you consider careful depending on your condition to have the most beneficial choice.


For the RV water heater with tankless, I am sure that you will want a more energy-efficient model in place of a tankless water heater that takes less energy. I strongly recommend you purchase one which comes with an Energy Star certification demonstrated the effect.

The flow rate and size

These features will let you know how much water a tankless water heater can supply you at the same time. Some people need one which can serve a whole household, running many applications at a single time while others just need a small and compact model, handling 0.5 gals per minute for a faucet.

Drain valves

If you want proper draining, the ideal location is to close to the base of your heater. I highly recommend you use a more durable material like brass instead of plastic for a long-term use.


Checking all features is a must to make sure it is cost-effective and providing you with several helpful features for a worthy investment. The temperature adjustment is one of the most important to check. Depending on each specific model, you can adjust temperature through a simple knob or a panel composed of an automated flow control.

The latter allows you to adjust and control water temperature. Besides, you also need to spend more time scrutinizing warranty and safety. Keep in mind another feature that is the glass lining in the tank takes responsibility for minimizing corrosion.

Digital Displays

I always appreciate the products which come with digital displays because it can help you customize operations as well as monitoring levels easily. Besides, it also features others including pressure readings, tank temperatures, and display collector, for example. 


The best tankless heater won’t take too much your storage area so if you have a limited space, pay attention to this feature. 

Other features

Apart from what I mentioned, you should also consider a simple and easy-to-understand interface and design. If you invest in a model that has a display, other members can easily operate while staying at home especially saving a lot of your trouble.

Benefits of a tankless water heater for RVs

This video will let you know more pros and cons of a tankless water heater of RVs:

Although replacing RV water heater with tankless takes much your time and effort, it’s worthy. You can get the benefits as follows:

  • A unit which runs normally doesn’t consume a large amount of power in a short time since it uses less propane than others. You don’t need to keep a set temperature for the water.
  • You can use instant-on water once you turn on the faucet. When the water flows, the sensor will signal the burner of the heater through thermal conductivity to create heated water immediately. What’s more, the tankless water heater is energy-efficient that takes less fuel and gives more potential energy savings

Read more: Girard Tankless Water Heater Troubleshooting

The bottom line

All we know the importance of heated water for our life and a water heater is one of the copper heat exchangers. Thus, you must maintain your model as well as possible. However, in some case, it’s hard to avoid some unlucky cases. At that time, you have to know how to replace RV water heater with tankless.

How To Replace RV Water Heater With Tankless

Leave a Comment

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Show Buttons
Hide Buttons