Electric Tankless Water Heater

[tarh2o]

I've been crawling the site and everyone has big praise for the precisiontemp propane water heater. Eventually I will get one of these for my airstream once I renovate it completely for full time living. I will get the floor vented model to preserve the exterior look of my wonderful 'stream.

In the interim I was looking at a tankless electric water heater and wondered if anyone had any experience with the electric variety. I am only looking to either run my shower or my sink faucet with this one (separately) and I will always be hooked to shore power (30AMP). I've found this one that is all electric and rated at 120v@30amps - Instant-Flow Tankless Instant Water Heater SR - Chronomite. The model I am looking at is the SR-30L/120.

If I hook this up and want to take a shower AND run the AC will this blow the breaker? I'm a little concerned that it will draw too much and I wont be able to run both.

As always any advice will be most appreciated.

Thanks

[mimiandrews]

Electric tankless water heaters use a lot of power. 30 amps is all you have for the trailer. The air conditioner is going to draw 14 to 15 of that when running and a lot more when starting up. That probably does not leave enough for the water heater.

I've been told that most of the smaller electric tankless units are intended to serve one sink for hand washing and not much more. Don't know if this one would be adequate for a shower.

Electric power management is kinda like a budget (with no credit card). Every unit you turn on counts as spending. When the total gets too high, the breaker (or is that the banker?) puts a stop to the spending.

[tarh2o]

Unfortunately I think you are correct. There is just not enough power to operate the AC and the WH.

Consequently I have found a great compromise with The PrecisionTemp TwinTemp Jr that will heat my water AND the airstream in those chilly winter months. Only downside is that they are very costly and require a good amount of space to plumb it in.

Guess I will have to just keep the little Airtron 4.5 WH until I renovate the entire airstream.

[mimiandrews]

We installed the Precision Temp 500 several years ago. Doesn't heat the trailer, but it does a fantastic job heating the water and uses very little propane.

BTW, a small electric space heater (carefully located with fire prevention in mind) does a great job of heating our Airstream. Electric power is usually part of the campground fee and I've paid for that anyway. Propane is on me.

1500 watt heater is 12 to 13 amps, so about half our power budget. Just watch out for the microwave and the hair dryer at the same time.

[GammaDog]

We use tankless in our home. Tankless heaters are usually rated by their ability to raise the temperature (in degrees F) of a specific volume of water flow (e.g. 1.5 Gal per min). Each of ours requires a 50 amp dedicated 220v circuit to achieve enough temperature increase at typical shower flow rates to take a hot shower. And we are starting with warm inflow water (our cold water at this time of year arrives at the house at 80 degrees F). I think our units are 40 degrees F at 1.5 or 2 GPM.

Based on my experience at home, I think the other posters are right... given sometimes cold inflow water at campsites, the flow rate of even a handheld shower and the electricity required to make a shower comfortable I think this isn't the right solution for the AS world.

[Wolf Alaska]

A point to consider, using 30 amps puts a strain on every connection & the 30 amp cord. I lost a fairly new twist lock 30 amp cord in March. Burned where it connects to RV. Had been pulling 20 to 30 amps most of the recent time...electric fireplace, electric water heater, MW, coffee maker. I'm using more dielectric grease to try to minimize corrosion & arcing on the new cord. BTW, when U lose U R 30 amp cord @ 6 PM, U R out of electricity until tomorrow when U can make the 110 mile round trip to nearest source for replacement. It was the A/S dealer in Defuniac Springs, Dixie RV. I turned the burned cord into a 26' 30 amp extension cord
Let's Roll !
Wolf

[Floatingair]

Floating air here. I use a 1500w flat wall panel. They take up no floor space.

[tarh2o]

Thanks to all for the feedback. With my current intent for the AS in the future I definitely will be using the PrecisionTemp TwinTemp Jr. I plan to boondock a bunch living on the BLM parks and on free sites I can find so limiting my electric consumption and water use will be a priority.

I'm already without a microwave (even in my home now) so my only large electric draw will be my computer/TV and the AC. My fridge, hot water and heater can run on propane so I should be able to go for a week or two depending on water and propane.

:-)