I'm going to use an Electric Tankless Water Heater for my 20x30 1.5 story camp. It will have a kitchen sink, bathroom sink, tub/shower and a washer. No 2 appliances will be working at one time. Any suggestions on one??? Will the Bosch PowerStar AE115 work??? Thanks Pete
What is your desired water temperature rise? That is, what is the coldest the incoming water will be and what is the hottest desired water temperature at point of use? You have to know that and the maximum gallon per minute flow for any appliances, etc. Then you can see if it's capacity is sufficient.
Thanks. I think the incoming water would be around 50 F. I'm not sure if my electric will support the bigger tankless systems. Alot of them require at least 150 AMP to 200 Amp service. I was considering getting a 30 gallon hot water tank that is electric and putting it in the bedroom closet. Pete
Have you considered a propane powered tankless? Oil-fired ones are also available and are probably the most efficient.
Quote from: peteh2833 on December 22, 2008, 09:44:47 PM
... require at least 150 AMP to 200 Amp service...
My quickee look at the Bosch heater you mentioned, revealed IIRC, that they recommend two 240 VAC 40 amps circuits, and a house minimum of 150 amps. I think I got that right. ???
I bought a Ranaii propane external instant water heater. It's rated at 7.5 gallons per minute. I can tell you that at the lowest temp here in Austin, 20 degrees (so far), there is enough hot water to run 2 showers at once at a burning temp to the skin. Inbound water temp is 40-50 degrees at this outside temp.
I briefly looked at electric and found they could not even come close to heating that much water. If you limited to 1 shower at a time and it was not too cold of intake water, it would be fine. The electric will spin that meter too. 40-50 Amps was common on the specs I saw
Ok. Thanks. I'll look into it. The electric ones are probably out of the question for me. Too much electricity. Pete
Is this place continuosly heated in cold weather? I too was attracked to tankless, but I was concerned that non seemed to be "drain-friendly" for emptying the water when we wouldn't be up there. Right now "up there" is about -10 degrees.
Looks like a regular tank model is easy to drain.
Boys are going up ice fishing tomorrow for a few days, but it's supposed to warm up to the 20's.
It won't be heated when I'm not there so I have to drain it out. I use it alot in the winter too. Pete
The renai is about as cold friendly as you can get they are not electric they are gas and LP units, but they have small electric heat elements that will come on to keep the unit from freezing and if that does not work there is a optional component that will cut the water to the unit and drain it. They also make a unit that is designed to mount on the outside which is nice with the smaller footprints of the homes we are building.
Here is a picture of our unit. We bought the valve pack with it that allows it to be drained at any place in the line. The Ranaii also has a few cool features with it's control pad. With a $200 upgrade you can have it fill a bathtub with an exact amount of water at an exact temp. Kinda cool, we don't need it but it's nice to know it's available. All in all, it was 1000.00 to buy the unit and have it delivered. We installed ourselves.
(http://www.ouramericanadventure.com/coppermine/albums/userpics/10001/DSC_7209.jpg)
Thanks. Pete
I don't mean to throw a monkey wrench into this discussion but, have any of you actually run the numbers and come up with an ROI on these units?
I was trying to decide on standard electric hot water tank vs a tankless gas model a year or so back and found I simply could not justify the cost. Tankless is nice and possibly more so if you are planning on being away for most of the time. But, for me, I go to my place almost every weekend and soon hope to retire there. That means a lot more hot water on an annual basis. That might throw off my numbers.
I don't recall exactly what the ROI was exactly but, it was a long time, like maybe 8 to 10 years? I went standard electric and got a 15 yr warranty unit for like $300 and installed it myself in a few minutes. The tankless would have required a vent in my roof, a penetration I did not want thru my new metal roof.
I just couldn't justify the cost of the tankless heater.
Okie Bob
Thats what I was thinking. I can get a hot water tank at Lowes or Home Depot for $250-300 and install it. Also I don't have to go with a large breaker panel to handle the tankless heater. Where did you put you hot water tank??? Pete
Good thoughts, as usual, BoB. :)
These heaters can be installed in the wall so you don't have the pipes exposed outside. For future reference.
Scott you are correct, you can install them in a wall. Can even be an inside wall if you go with electric. If you go gas, you have to go to an outside wall and put a vent thru the roof or the wall. I personally don't like either option.
And while on that subject, I did not need a single hole anywhere in my metal roof. I used the Studder valves for vents inside
and they are working fine. No problme at all that I have noticed yet.
Okie Bob
Tankless is more initial investment but they have much lower operating costs, especially for weekend or periodical users. Also, a conventional WH is doing good to last over 12 years and tankless are usually good for at least 20. In final analysis, payout will depend a lot on the cost of energy in your area. Installation at least in new construction is not a difficult DIY project and they save a great deal of space in a small cabin setting. I believe it is largely a personal choice matter with no really clear financial factor past initial cost.
I really wanted to go tankless and tried everyway possible to justify the extra cost to no avail!!! I still have a house in town that I'm getting ready to remodel and probably will go tankless mainly because the current gas hw heater would be easier to replace with a tankless
model and save room in the garage. Vent, gas and water lines are already perfectly located to put in a tankless system. I love them, it just didn't make sense for my lake house, financially speaking.
Okie Bob