OT-tankless water heater

I'm looking for a tankless water heater for my farm shop restroom.I'm tired of replacing regular water heaters.The rheem RTE7 i'm looking at seems to be the right size.Anyone ever use one of these? I see some bad reviews saying they only warm the water and some say they don't last very long.Then some say there great.I haven't found anyplace that actually sells them,they all go through a third party,even at lowes and sears.They have to special order them through another company,can't go directly to Rheem.

I had a small under sink one.It did ok but the water went from hot to warm real fast. I wouldn't buy another one.

We had one when we built our house 25 years ago. At that time we used our hose here as a weekend get away place and a hunting camp. It worked great. If you turned the temp up it would scald you. But after 4 or 5 years it started to get lime up and you would run out of hot water in the middle of a shower. I bought some stuff from a pluming supply place to clean the lime out, but it never did work as good as it use to so I took it out. The one we had was a Poloma brand. At that time no place would work on them because they did not now any thing about them. I am sur the ones nowday are much improved. Ours was an LP model

My ex in-laws have a tankless unit in one of their houses. I"d guess it"s been in use for 10 years or more. I don"t know the brand but could find out. It does require periodic cleaning, maybe annually, but nothing extraneous. It has to fairly simple to do or else my ex father-in-law wouldn"t have messed with it.

Hope this helps.

Anthony

If you have hard water like we do here in the TX Panhandle it will not last as long as a tank one does. I have a tank type heater in my house, have had it for 10 yrs now. I clean it out twice a year and it's still going strong. I have had plumbers tell me that if you do not have a water softner do not get a tankless heater.

They're all a PITA. Choose your poison.

Gas, LP, oil or electric? If electric flat rate power or time of use ?

If you are on a well you more than likely will not like how they work. The instant water heaters need a constant pressure and flow to heat evenly. My sister had one. When you would start a shower the water pressure/flow would be high. You adjust your temperature. As you shower the pressure/flow drops. The water becomes hotter. The pump kicks in and the pressure/flow goes back up and the water cools down. It was always yoyoing around.

Plus theirs did not last two years and it quit. It was a propane one.

My kids have a tankless water heater in their house that was completed in 2009. They are on city water.

Once you have hot water at a tap theirs will maintain the temperature evenly. It will supply the proper amount of hot water whether the showers are going in both bathrooms, the dishwasher is going, and the washing machine is going with the latter two shutting their flow on and off.

Theirs is indeed a good one that seems capable of adjusting to needs whether in summer or winter.

The properly sized unit was selected by the plumbing contractor and I will give him an A+. It is a Rinnai of some model.

The only issue I have with them is that you have to run so much water through the lines before you actually get hot water. It is a pex tubing and manifold system with a different line going to each tap. Ex: water to a shower, and water to the lavatory a few feet away. Lots of wasted water but it should help to keep sewer lines well flushed.

I tried one (electric) a couple of years ago when my tank went bad. Taking a shower was a real thrill. I was either freezing or scalding depending on the whim of that torture device. I threw it a far as I could and went back to a tank. Change is good, if it's changed back to how it once was. Ahhhh, life is sweet again. TDF

I've had a Rinnia LPG tankless hot water heater now for 5 years now and there hasn't been any issues. I keep it set at 120 °F.

I have a 350ft well and zero issues with temps going up and down with water pressure or flow. There are other issues at fault if you're getting those problems.

The same holds true for getting hot water to the facet. It takes no longer or extra water to get hot from a tankless as apposed to a tank-type; unless you put the tankless 30 feet further away. the run of purging water is typically the same. If fact, in my case, I was able to move the hot water heater closer its final usage when compared to the boiler, I use less water in purging the pipes of cold water.

For what its worth, I won't ever go back to a tank heater or a boiler for domestic hot water. It's not worth it.


bob

The key thing is that you have to be sure that it is properly sized for your demand. For a shop bathroom your draw will be low and short so I wouldn't see where you could go wrong. If your water is hard it will get coated and lose effectiveness.

The installation is the biggest problem in houses. You have to install a separate stainless steel vent for every heater used if installed properly. Gets a little pricey.

Jim

The standard tankless heaters do not heat water to any given temp. They only work by temp-rise. The standard 120 F thermostat setting has nothing to do with how hot the water is actually heated.

If you've got 45 F degree well water (like all my houses have)- that Rheem will only raise the temp of the water by 20 F at full capacity (2.5 GPM). That means - if you've got cold well water - your "hot" water will be 65 degrees F instead of 45 F. If you only run your water at 1 gallon per minute, you get a 40 F rise. Much better for small usage and worthless for high flow (like taking a shower?).

What the heck is happening to your old failed heaters? I rarely buy new. I buy used - usually $50 for gas or electric and I've rarely ever had one go bad. I did have to fix a few with minor issues. I've got four houses - all with used tank heaters and some have been in use for 30 years.

Note also that standard tankless heaters do not work with preheated water. If you heat your water in the summer with solar, or in the winter with a wood fire - standard tankless heaters can't be used. There are special and more expensive models made for that.

A well insulated tank heater is just as efficient as a tankless - and cheaper - and it actually keeps hot water on hand.

Rheem RTE 7 Indoor Series Electric Water Heater
Required Breaker – 30, 240 volts
Maximum Flow Rate - 2.5 GPM
Heats with 20 F rise at 2.5 GPM, 40F rise at 1.2 GPM, 90F at .5 GPM


Rinnai Model Number REU-VB2020FFU-US
15,000 - 150,000 Btu/h (Natural Gas and Propane)
Hot Water Capacity 0.6 to 5.3 GPM
Gas supply: 3/4 inch MNPT
Cold water inlet: 3/4 inch MNPT
Hot water outlet: 3/4 inch MNPT
Efficiency 82%
Temperature rise at 5.3 GPM is 40 degrees F, 125 F at 2 GPM

Rinnai Model Number REU-VB2528FFUD-US
Hot Water Capacity 0.4 to 7.5 GPM (40° F rise)
Propane: 82% Residential: 98°F - 140°F
10,300 - 180,000 BTU/h (Propane)
Gas supply: 3/4 inch MNPT Cold water inlet: 3/4 inch MNPT
Hot water outlet: 3/4 inch MNPT

I've got one (an LG) 24kw that runs 160 euro new (other side of the pond)... It runs on 380-400 volts... I run the hole house with it when we don't need the furnace (boiler)... It does fine but you have to turn the water almost wide open for the flow. It can blister you tho if you aren't careful...... There are smaller one point (sink) ones that run on 230 volts that are nice also. Probably not a good option for supplying hot water for wash machine/dishwasher tho...... Don't know what they are pedaling to you folks for such high prices..... Common in older places here and I have one in the shop is a 5 to 15 liter tank than you can just turn off/on as needed to warm your water to wash...... You would probably be better off with a small tank heater....

Don't buy a tankless hot water heater!! They just don't perform as advertised. They are way too expensive for the mediocre performance they produce. We had far more adequate hot water supply with the regular gas tank heater that we replaced.

I think the problem is that that DO perform as advertised if a buyer actually reads the small print and specs. Key thing is they do NOT heat water to a preset temperature.

What voltage do they run on?? Most here run on 400 volt and can be set at 35, 45, or 60 degrees celcius for the mid range ones, cheap can be set warm or hot and expensive can be set at whatever tempyou want (that's where the fineprint and BS comes in....... Can't imagine 110 or 220 volts working out tho (or I just don't understand electricity).......

They are hungry tho...... Unhooked ours (switched to oil) and the electric bill was less than half for the year.....

LJD, you might want to check your heater, it's probably undersized; just like most anyone else that has or had a tankless heater and is complaining about cold or cool water.

My tankless heater is set at 120°F and will burn you if cold water isn't introduced. And yes my water is plenty cold coming out of the well, through a whole house filter and a water softener. My heater rise with a 2.5GPM (using your example) is about 120°F. Check the link. Plenty hot enough to shower and and run the dishwasher at the same time.

Efficiency, is much better than having an an oil fired boiler kicking on in the middle of summer with nobody using hot water; only because it dropped down.

I burned about 250 gallons ($2.18 gal) of propane for a household of two, for the year, just for hot water. I would have burned around 500-550 gallons ($3.50 gal) of heating oil for the same hot water only. The house is heated by a wood stove. Which is cheaper for hot water? A tank water heater would be more efficient than my boiler for domestic hot water, but not nearly as efficient as the tankless heater.

Tankless was also energy star rated so I could get a tax credit with it.

bob
Rinnai tankless hot water heater