Tankless water heater
Planning to use tankless water heater(s) in new house with 2 1/2 baths. Looking for advice regarding greater energy savings, electric or propane. Also preference for either whole house unit or single point models? Thanks
A friend told me about these & is really interested in getting it installed. She said it was her understanding it really saves on electricity but possibly might use more water if the unit is far away from your shower, for example if you don't want an early blast of cold water. I have that now with a regular water heater. Another advantage is its small size compared to a regular water heater which is a good thing in condos or smaller homes.
I'll be interested to read more replies because my water heater is getting to be a bit elderly but I'd have to have electric. Didn't know they also worked with propane.
I am a plumbing contractor, and install both electric and gas in California. More natural gas then propane, but natural gas will run out before it gets to my spot in STX. The electric tank less heater that can handle 3.0 gpm(shower is 2.5) takes 150 amp you can not put it where the old tank heater is. If you pull new wire, most house panels don't have room. Most uses for them is in a gust house. They cost much more to run then a normal electric say 50 gal, accept if you are not using it, that's the gust house thing. If you have a propane tank then I would do Bosh tank less. They have one that dose 3.5 and one 7.0 they are $550 and $900 They are both good, the 7.0 is nice for bigger house if laundry and shower go at the same time, or two showers. You will save money compared to gas tank heater. But you will never get the cost of the propane tank back. For new construction my pick is 50gal tank heater for STX. The new ones are very officiant they are 30 to 50 amp and the weather there will help with the lose of heat, if you lose any with the way they are insulated now.
I installed an electric tankless heater in my condo. It's nice to regain the space formerly taken by the hot water heater!
I used an eemax model EX280T2T (www.eemax.com), purchased online from Ira Wood & Sons (www.irawoodinc.com), along with other plumbing remodel supplies. It is installed in a 2 BR/2BA condo.
In general, I'm very pleased with the tankless. One thing, though-- there's a loud clack when the the power cuts on. Not sure, but I think all of the tankless heaters have an audible click or clack when they cut on.
I haven't put it to the real test since I haven't had guests but I don't anticipate problems. One thing to check before purchasing is your water pressure. Mine barely made the minimum requirements for a tankless.
The rep at eemax was very helpful when I called with various installation questions. I did have an electrician run new power to a subpanel to feed the heater. It required three 220 lines which come on in sequence depending on flow demand. Since I rarely have more than one hot water tap on at a time, I doubt that all three power feeds have ever turned on.
If building a house, I would probably go with point-of-use tankless heaters in order to save water. Or perhaps a combination, with the goal being to have the tankless heaters as close to the taps as possible. My whole-house tankless still wastes considerable water while the fresh hot water travels from the unit to whichever tap is on.
Simer makes a pump called Pressure Booster 115 volts. Easy to install in line, before filter system. You just plug it in and set the easy to read dial on the pressure you want. I put one in my dads cabin and I had doubts it would do what it says it can do. That's why he got the trial run on it. It works better than I could ever imagined. Pressure is not a problem any more. If you want to set it at 80 psi and have fire hose like pressure you can. 40 psi is normal and it holds it perfect. No need for pressure tank with the air bladder any more,I know you guys like them small. They are bit pricey $350 would be a fair price. They are new so reliability is not tested by me.
Thanks to all for your responses.
ashultz- Your preference for new construction is a 50 gal. tank heater, not a tankless. Do you believe electric costs for the tank heater would be about the same as a tankless system? Is it because of the modest difference in temperature between the cistern water and the hot water that does not require a lot of electric to maintain?
Jules-Have your electric bills gone down since installing the tankless?
My plumber recommended a tankless after hearing that Cowpet was replacing their water heaters with tankless. He did not seem that familiar with them himself and I have been researching on my own. I plan on renting my villa part year which will put more demands on the hotwater supply. Due to the high energy costs in the VI, I want to save as much as I can.
The tankless electric for normal use requires more electricity then a normal heater. If the place sat vacant a lot you might get some money back, or throw the breaker on your tank heater. The gas tankless are more efficient then old tank heater. Gas tankless will be the only way for gas heater some day soon. With electricity it is just better to heat the water slow. The reason I am going electric is, don't want to plumb house for gas, the tank must be buried in my development. That is lots of overhead to get back and price can change on propane gas. There is also the Hope of solar some day.
But I thought the advantage to electric tankless would be savings on electricity since the water isn't being heated or kept hot constantly. The water would only be heated on demand or am I missing something? What's the lowest the water pressure would need to be before it doesn't work. Our pressure isn't the greatest where I live.
another consideration i have been warned about is the tankless are more prone to fouling inside the little tubes that make up the heat exchanger. maybe this is only for the gas heaters, not sure. the electric is probably just a small container with a couple of elements in side.
so conditioning of the water might be more important than in the typical storage tank heater.
It use three time the electricity when they are both on. The insulation makes a new tank heater kick on around 6 times in 24hr not for very long, with no use. Electricity is just not the best way to heat water and slow heating it is cheaper. but you could run out of hot water. There best use is a gust house that may get little use.
10% of the energy used by a water heater is used to keep the water in the tank hot. The thermostat cycles on and off all the time. This is standby loss.
Another savings is that you can set your water temperature to 110 since you will never run out with a tankless heater. Think of the energy you waster in a shower with a convential heater set to 135. At the begining of your shower you need to blend the hotwater with cold water so you don't scald yourself. This is hotwater you paid a fortune in the VI to heat. The temperature has to be this hot so you still have warm water at the end of your shower.
The studies project you will reduce your energy consumption by 30%. I am traveling now, but when I get back next week I will post a link to a site where they document the savings.
I have a tankless heater and it has worked fine for me. They also have a longer projected life than a conventional heater.
In the UK, I had natural gas tankless in the kitchen to heat water for showers, tub etc and radiators. Both bathrooms were close to kitchen. I loved it.
InPR, we had a small direct heaters (electric, I believe) on both showerheads. Probably illegal in the civillized world. We also had a propane direct heater in the kitchen for the rest of the domestic water. Worked out to be quite economical. Mind you, the "mad leccie" in PR was cheaper than Wapa's offering. Propane was pretty cheap too.
Solar water heaters aren't allowed in all condo associations. One owner had it on the roof until Marilyn came along but they're no longer allowed here. Doubt the tankless is an option for me since I don't think it would save anything. My water as it is never gets hotter than about 115° & it would have to be electric, not propane.
Here in Puerto Rico we went with a Marey LPG instant on Gas hot water system. It works well and I am realy happy we went with LPG and not Electricity. The unit costs $200 at Sears and $180 at Walmart. Simple to put in and hook up. Doesnt take much space. I don't worry about carbon monoxide since the house is so open. It needs to be proteced from the elements so it's installed inside.
Here is a picture of it above the washing machine. http://thekrusechronicles.blogspot.com/2007/11/cat-just-ate-gecko-we-have-hot-water-i.html
Hi, when I visited China several years ago, small LPG point of use water heaters seemed to be the standard thing in most apartments. Mine needed service when I was there. They just removed the old one and replaced it with a refurb in 10 minutes. then presumably did not discard the non working one but refurbed it. Very efficient modular system. Also, there was often no shower curtain - you squated in the tub to get wet, turn off the water to soap up, turn it on again to rinse off. Not the long hot shower many of us are used to, but again, very efficient! Maybe there is a lesson in there somewhere.
If I were you, I would not even come close to entertaining the idea of an electric instant water heater. The ones you find are only good for the under sink applications with enough power to make warm water for washing your hands. Besides that the power it would require would be huge. If you really want to go this direction-you had it right with the LP one. While you will burn LP faster while heating you only burn while you need it and not maintaining a temp in a tank. Do look into the venting requirements for the unit though.