How to Convert RV Water Heater to Tankless

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A ready supply of hot water is one of the most desirable home comforts and vital features for RV owners. Tankless water heaters are on-demand devices and the hot water supply has no depletion. For endless amounts of hot water in your shower and sinks, read this guide on how to convert an RV water heater to tankless. 

Differences Between Tank And Tankless Water Heaters

A tank water heater is also a hot water storage device. It is filled with water that heats to a pre-set temperature with either an electric or propane element. A thermostat keeps the water at that desired temperature. The energy is used around the clock and is ready for use when your taps turn on.

A tankless water heater produces hot water using a propane or electric element. It heats water only when the water system is in use. The cold water supply runs through either the propane or electric element, which heats in passing. 

Different Types of Tankless Water Heater

There are two types of tankless water heaters, and that’s electric and gas. 


Electric water heaters, most commonly used by RVs, operate on electricity and do not emit greenhouse gases. They are friendly to the environment and are quite efficient. They install easily and can connect to a battery, solar panel, or any other power generator trouble-free. 


Tankless gas water heaters mostly run on propane. It requires a source of gas and pipe for the gas-to-unit transfer and a flue for exhaust release caused by burning gas. Tankless gas water heaters are less friendly and less efficient to the environment. They also require a much more complicated installation without a propane system already in your RV. 

Also Read: Best Electric Tankless Water Heater for RV in 2021

The Benefits Of A Tankless Water Heater

Tankless water heaters are very beneficial. Here are the two main benefits that a tankless water heater provides: 


A tank water heater holds about 10 gallons of water or less. A tankless water heater can supply you with an endless amount of hot water at any time. So, a tankless water heater is enough to shower your whole family and enough for any other hot water-related needs. 


As mentioned earlier in the article, tankless water heaters are much more efficient. They don’t have to continue to keep up with the tank water’s temperature, therefore, using less electricity or propane. 

Steps to Convert Your Water Heater to a Tankless Water Heater

Once you’re ready to convert your water heater to tankless, follow these four simple steps:

  1. Drain the Tank and Disconnect Supply Lines

    Make sure the water connection and propane are off, then drain the tank. Disconnect the old heater from all service supply lines, as well as the electrical to ensure safety.
  1. Remove the Old Unit

    Clear the outside flange of any waterproof sealant with caution, then take the mounting fasteners out using a cordless battery drill. After that, carefully pry the mounting flange off the side of your RV using a hammer and chisel. 

    Take your time with this to avoid damaging your RV. Clean the area, connect the new heater and reconnect the service lines after removing the old unit. 

Also Read: How To Remove an RV Toilet?

  1. Install the New Tankless Water Heater

    You really want to take your time with this process. Be sure that the new water heater unit doesn’t snag onto anything when sliding it into the recess. Check that the unit is completely seated and at sitting level. 

    Once that’s done, you may slightly pull out the unit to help it balance securely and give enough room to seal the flange. Place the unit into the hole, then position and seal the door. Check that the new water heater’s mounting holes line with the old water heater’s holes, and drill new holes if necessary. You may install a few mounting screws, but do not torque them up just yet.
  1. Reconnect to Service Lines

    Be sure to connect the right water lines to the correct points on the heater without cross-threading and over-torquing any of the fittings. Tightly screw and secure all screws into place on the outside flange. Attach any vent fittings, place the door on the heater and add the hot and cold water connections to the unit. 

    Turn on the hot water, examine its flow and set your desired temperature. Now you’re done!

Choosing A Suitable Tankless Heater

When choosing a suitable tankless heater, you may want to consider a few things: 


You want your new water heater to be as close as possible to a straight drop-in replacement. For assistance, contact an installation technician or sales representative. 


Pay close attention to the heater’s venting system position. The new water heater should vent in the same position as your old one to avoid having to make any costly, time-consuming RV modifications.  

Fittings Compatibility

Compatibility with the old water and propane connections is vital. This helps prevent delays and extra expenditure when converting. With that said, there is a wide range of available adaptors. 


For more information on converting to RV tankless water heaters, visit our site or contact us today!

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