Moving Our Hot Water Switch

8 minute read

One of the cool innovations in recent years for RV’s are the instant hot water solutions. The water heater in the RV I owned previously required approximately ten minutes to heat up and didn’t last very long. The idea of unlimited and instant hot water is fantastic - but, we had to go outside to turn it on.

Instant Hot Water

The first versions of the instant hot water concept used in RV’s suffered from a tiny problem. You had to run the water for a little bit to get the system to kick on. This made those first instant hot water systems pretty painful for boondockers. This required you run through quite a bit of your fresh water tank before your water temperature was comfortable.

Things have changed. Alex and I benefit from this RV Hot Water Heater industry continuing innovation in this area. Our unit is a hybrid approach. Our hot water heater has a really tiny tank that the heater maintains at a constant temperature. The water in the tiny tank is ready for use instantly and is enough to serve you hot water until the hot water heater has a chance to heat up. It only takes a few seconds before the unit is serving a constant stream of hot water.

The Problem

The concept described above for hot water is fantastic. The implementation in our RV was unfortunate. Why? The switch to flip on our hot water heater was outside.

There are two settings on the unit outside. The Comfort setting keeps the water tank at 120 degrees F. Keeping the water at 120 degrees F means hot water is ready at all times. Our version of this water heater also circulates the water to the faucets. The water is instantly ready to be used as soon as you engage the faucet.

The other option on the hot water unit is Economy which keeps the tank at a brisk 40 degrees F. In this mode, the unit behaves like previous models. The unit heats the water only after it detects the water is running. This takes several seconds. Those seconds waste precious water.

Ideally we’d leave the heater on the comfort setting all the time but this would burn propane at a constant tick. Additionally, the unit isn’t really meant to run while you’re driving. The flame can be blown out by the wind generated from driving.

Since the On/Off button of the heater is outside, this means we have to go outside every single time we want to use hot water. Bummer!

The Solution

image-right I did some research on the heater in our unit. I learned that the model installed in our RV was modified in the middle of its production year. Our unit did not have a remote but the newer units have a ‘remote’ that runs into the RV. You can control the comfort settings from inside the RV.

The remote switch gave me an idea! I might not be able to get the wires run to where they install the switch on new units; but!, what if I could flip the unit on-and-off inside the RV? I could leave the settings outside on the water heater always set to Comfort and cut power to the unit inside.

I dug around the RV and discovered there was a panel under our sink that exposed the top of our generator and the back of our hot water heater. A little more poking around I found the hot wire to the heater. This was great news!

We took a quick trip to Walmart to look for switches. Walmart was lacking a bit in options. We found something good enough to make it work. They didn’t have proper wires for running electricity so we bought an extension cord and cut it into a good-enough solution. I gave Alex a crash course in AC and DC electricity. I explained what we were doing and how we would try to hook up the heater. We tested our theory by hard wiring the scenario. Everything looked good. I convinced Alex to try wiring up the switch. She had it wired up in less than twenty minutes with very little guidance.

We made sure to do this in such a way that we can reverse all our work without any permanent changes to our coach. When we sell the RV we might want to undo the change. We used a commercial grade velcro to mount the switch. The cables were joined with basic wire nuts. After Alex was done we were able to flip on the heater from inside. That may not sound like a big deal - but, now, I can flip on the heater right before I get in the shower. By the time I have taken off my clothes and gotten in the shower the water is already extremely comfortable. It only seems to take forty five seconds for this fella to generate the pre-heated water.