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There are a few options to help your factory water heater improve your heating payback time. You can install what is called a hot rod, which is an electrical heating element that replaces the anode rod in your water heater. This rod uses 400 watts of AC power to heat the element and helps recover the gas portion of the heater. This is a somewhat viable option for extending hot water supply time, but some water heater manufacturers frown on its use, stating that it can void your warranty because the lightning rod no longer provides the corrosion protection that the anode rod does. standard. However, you still won’t get the hot shower of your dreams with this option.
This is where the tankless water heater comes into play. There are two types of tankless water heaters: electric and gas. The first type works similar to the hot rod in that an electric heating element heats the water. But that’s where their similarities end. Instead of filling a tank with water and then heating it, the electric tankless heater senses the water flowing through it, activates the electric heating circuit, and the water is heated instantly. It is 100% automated. As soon as you turn off the water flow, the heater will turn off. The water temperature is regulated by the water pressure. Less water pressure means more heat, and more water pressure equals less heat.
The gas type works much like the electric heater in terms of sensing the flow of water and heating it up instantly. But in this case, a propane burner heats the water. And there are no big demands on electrical power as with electric heater. Both can provide a constant flow of hot water almost indefinitely, but the gas type will be better able to meet demand and fit more easily within a typical RV environment.
The easiest way to retrofit your RV with a tankless water heater and get that amazing endless shower is to use an in-line shower head replacement device. This type of heater uses a powerful electrical heating element to instantly heat the incoming water just before it leaves the shower head. It can raise water temperature up to 50F at a flow rate of one gallon per minute. This should be enough to supplement the factory water heater so that while it recovers, you still get reasonably hot water. The only drawback is that the unit draws a lot of current, more than 20 amps. You will need to dedicate a breaker and receptacle for this unit if you decide to go this route.
If you’re getting away, or camping without hookups, then consider doing this mod with a custom installed gas tankless water heater. These units do an excellent job of providing instant and sustained hot water and can be used to supplement or completely replace the standard RV water heater. However, there are a couple of very important things to consider before making the mod. The first is ventilation requirements. Like the heater in your RV, the tankless heater emits CO2 when the burner is on, and the CO2 must be vented out of the RV. Three-inch piping is a minimum and must be exhausted through the roof or sidewall with proper vent pipe and cap.
You should also consider where the drive is mounted. The area must be free of anything that could come into contact with the unit. Also, the unit must have some ventilation or fresh air supply. This is not critical, but the burner needs oxygen to work. For starters, most standard RV cabinet doors don’t seal very well, so there must be enough air supply to provide adequate performance when the unit is mounted in areas like this. In either case, follow the manufacturer’s recommended installation procedures if you are unsure. This includes connecting the gas and water supply, and any electrical requirements necessary to power the unit’s circuit board.
Finally, and of course the most expensive of all options, is to completely replace the factory water heater with a replacement tankless heater made specifically for RVs, the RV500. This is by far the easiest way to have endless hot water. Replacing your standard water heater with the RV500 is surprisingly simple. Start by turning off the propane and draining your water heater. Remove gas supply line and water lines. And disconnect any electrical wiring. Unscrew the set screws on the outer frame of the heater and the unit should slide out.
To install the RV500, reverse the steps used to remove the factory water heater. Most likely, the gas supply pipe and the water inlet and outlet pipe do not require any modification and are directly connected. The heater requires a 12 volt power supply for the circuit board to function and control the unit. It has a very low current, so it should be able to connect to most nearby 12 volt sources. Once installed, simply open any hot water faucet and the unit will turn on automatically. Closing the hot water faucet in turn turns off the heater. It is quiet and will keep up with any demand. Now you can take your time showering, but you may need to retrofit your RV with larger holding tanks!