On demand hot water heater upgrade

[peach680]

Hello,
I have a leak on the bottom of our hot water heater in or x23f. Wanting to upgrade to a tankless. Has anyone done this. We only camp where we can have electric hook up. Has anyone done this?

Really only need hot water for dishes and hand washing.Always use shower house at the camp grounds.

Looks like this one my be what i need. https://www.homedepot.com/p/Chronomi...20-I/307248643

Any thoughts?

[RetiredOne]

Just make sure your electrical system can handle it. That heater is 1800 watts, 15 amps.

[oldmanAZ]

Do some research in this site. Not everyone with an on-demand unit is pleased with them. Some swap them out for a unit with a tank.

Do you have water and sewer hookups where you camp? From what I've read on this site, some on-demand systems seem to work better when the flow is not repeatedly stopped and restarted.

[blujay40]

The one you linked could work for a single point of use such as the kitchen sink but as mentioned earlier, you better make sure the electrical at the point of installation is robust enough.

That 1800w water heater is gonna draw 15 amps which is the max for almost every electrical circuit in an RV. So if there is any voltage loss due to the way the circuit is run or that circuit is also powering anything else at the same time, you can expect the breaker to trip quite regularly. You would probably be better off putting it on a dedicated circuit with heavier guage wire and breaker than what is commonly found in an RV or plugging it in directly to the pedestal bypassing the RV wiring altogether.

That's why all RV specific on demand/tankless water heaters are propane and not electric. Just too much for most RV electrical systems to handle.

[norty1]

Most residential on demand units operate on 220v because of the lower current demand.

I have never seen a 120v unit in an rv but it may be worth a try.

[Jagiven]

Not sure what my thoughts are yet! I have an on demand (natural gas) at home, its a love hate relationship. I would think the electric model would not have the delay due to burner purging that my natural gas unit has. At the same time, I doubt it can go from off to full on instantaneously, so there maybe some delay, so you may also get a slug of cold water every time you turn the faucet on. especially while doing dishes.

At home, when I wash dishes (by hand) I leave the hot water faucet open to keep the water heater running, to avoid the cold water slug. In an RV, this could be a terrible thing if you do not have full hookups.

As for wiring it in, just set it up to use a 12 gauge extension cord, to plug directly into the shore power post. No issues then with over loading the TT's electrical system.

My next question/concern, the unit you linked to says "SR-Low 0.35 GPM" is 0.35 gpm, the max flow rate through it? Or does it turn on at 0.35gpm?

From the owner's manual;

"OPERATION INSTRUCTIONS
Turn the hot water fixture to activate the flow switch. The flow switch activates at .4 gallons per minute (GPM) and deactivates at .35 gallons per minute (GPM).

If you increase the flow rate of the water above .5 GPM the water temperature will become cooler. Cold water can always be mixed just as with a conventional system if using a two handle faucet.

Once you decrease the flow rate to .35 GPM the unit will deactivate. It is not advisable to operate the heaters at .35 GPM."

I also see, at 0.4 GPM flow rate, you can only raise the water temperature by 30oF above the inlet temp. So if the water temp is 50of out of the faucet, the hottest temp coming out of the water heater is 80oF.

More I look at the unit, the less impressed I am. The SR20L 220/240 volt unit can raise the water temp by 81oF @ 0.4 GPM