Drain your water heaters

Very scary hotwire.

e-tankless: Welcome. Thanks for the info. I think the 120 amp breaker is troublesome to many. Is there anything regarding this you might have seen that would be helpful to know? I myself have 200 amp service, take an electric stove, cooktop, dryer, washer, and some planned additions (heat pump for pool & central air) and there is no room for a 100amp addition. I'm not sure what an upgrade from 200 to 300 takes or costs (noting that there will be more amps in the breakers than the total service as well in many cases to account for not all items being on at once).

Also, one of the earlier assumptions was that if you are in a colder climate, the water may only be warm. Is this handled by sizing the unit properly?

Being that you apparently are quite familiar, I'm curious how you handle such concerns with prospects.
 
Rupp,

You are correct. My math was wrong but it seems that it was even more wrong because the unit only draws a max of 99amps.
 
You are all very welcome for the information. We feel very strongly in tankless water heaters, but we recognize that they are not suitable for all homes. Customer education is therefore very important to us and the industry as a whole - we want those who install tankless to have all of their expectations met or exceeded.

A 120 amp breaker is indeed very large and the home's electrical service must be examined to ensure that sufficient electrical service is available before considering the installation of a tankless water heater. That said, most homes with a 200 amp electrical service are able to install a tankless water heater, even the larger (18 KW+) models. This is true even with homes with lots of large electrical applications as it is very rare in most homes that laundry dryer, AC, heat, stove and hot water will be running at the same time.

I happen to have the Model 240 myself and a 200 amp service to my 2-storey, 3800 sq foot home. I have a large, rather inefficient AC, electric stove, electric dryer, and of, course the Model 240. My heat is provided by a standard natural gas furnace.

In some regions, the Model 240 which normally requires a 120 amp breaker, can be installed with a 100 amp breaker (max. power is 99 amps).

The most important thing to remember is that the SETS tankless water heater modulates its power dram in accordance with the user's power setting, and the flow rate. It will only draw its full power rating when you are running it on the highest user setting and demanding a strong flow of water (generally 3 GPM+). Most of the time, it is going to consume far less than full power. This is true of a lot of your other appliances too. For instance, a stove doesn't necessarily run at 40 amps just because it has a 40 amp breaker serving it. If you only have one or 2 burners on, it may only be drawing 10 amps, etc.

Upgrading to a 300 or 400 amp electrical service can be quite costly. If you are buying a tankless ONLY for operating cost savings, this will likely create a payback timeframe that is unattractive, however, if you are buying a tankless for other reasons (constant hot water, space savings, etc.), it may still be worth it - only you can decide that.

As for the colder climates, there are models specifically designed for incoming water temperatures below 50F. Proper sizing of a unit is important for all climates.

At a flow rate of 2.5 gallons per minute, the larger SETS models can increase the temperature of the water by:

Model 280 (27 KW - 113 amps): 76F
Model 240 (24KW - 99 amps): 65F
Model 220 (22KW - 94 amps): 60F
Model 180 (18KW - 79 amps): 49F

So, if your incoming water temperature is 42F, you would be able to heat the water to 118F with the Model 280 or 107F with the Model 240, etc.

The average shower/bath is between 98 and 105F, depending on your personal comfort zone.

We have units operating in Alaska as well as Canada's arctic - tankless can work in northerly climates depending on your flow rate needs and proper model selection. In some cases, you may have to slow down the fill rate of large roman or jacuzzi tubs to get the best results during the winter months, but at least the whole tub fills before you run out of how water.

Please let me know if you have any other questions!
 
Great info Tankless. Thanks a ton.

I do have a question though. You've talked pretty extensively on the electric heaters so far. By any chance do you have/sell gas models?

If you do, can you give us your run down on why tankless gas units would be superior to tanked gas units?
 
Hi Micah,

We do not sell gas tankless water heaters. We did briefly a few years ago but we found the demand to be rather poor due the much longer payback time.

Due to the serious venting, fresh air supply, and fuel supply requirements of gas tankless water heaters, they tend to be really expensive to install. Venting diameters generally need to be increased, combustion air supplies need to be provided and in some cases, the diameter of the inlet gas line need to be increased. Futher, they are also more expensive to buy, have shorter warranties, and require more maintenance than an electric tankless. Consequently, the payback time compared to a traditional gas tank heater can be 8-10 years or more. For most people, this is too long.

Gas tankless have one advantage over electric models - they are capable of producing higher flow rates, but most families simply don't need these higher rates.

Sorry that I can't be of more help on the gas side.
 
Hey where'd you get the picture of my shower? :)



The last tank heater I had didn't seem to lose much heat to the room. It wouldn't even be warm to the touch on the top. It also had a check valve in the pipe.

It seems to me that you should mount tankless heaters next to the demand, or they kinda lose their point. Then you gotta run the big wire there too. More than one bathroom or kitchen and...lotsa money.

One time I had a small bronze pump hooked up to my upstairs bathroom hot water pipe, and a third pipe to return the water to the heater until it got hot.. I don't know if it saved much or not, but I did think it was neat that I didn't have to run water down the drain until it got hot. Living in the country, and having to pump my water and septic it as well as heat it ... it made me feel a little better.
 
I installed a tankless gas whole house water heater about 6 weeks ago. Its got its pro's and con's. It is rated 4.3 gallons per minute so its supposed to be suitable for 2 showers (I have only one). For the shower its fine and you never run out of hot water. For the tub the flow rate is higher and it only gets warm (the main draw back). If your water pressure is low it may not kick on unless you make adjustments.

I did the install myself. It is a direct vent model so I had to mount it on an outside wall and vent it outside similar to a dryer vent. Because of the I had to redo a lot of plumbing and the gas line as well. Total price about $600.

I left the old hot water heater in place and isolated it with valves. If the tankless goes down I can fire up the old heater in about 30 mins (flush, fill and let it heat up).

I have a friend out of state that has an electric and he loves his. He did nuisance trip the main breaker once he said. Also his lights dimmed when he took a shower he said but I think he was exaggerating.

Anyway that my knowledge of this.
 
Digger, which one did you get? I need to install one soon, and so far I've looked into Bosch, Noritz and Rinnai. What were the cons?
 
I went with an OMEGA2000 unit (do a google search). It was $475 on ebay but you can also buy it directly from them same price. Its probably one of the lowest priced units out there. The Model is OME 514PV. It can be direct vented.

I have not used any others so I cant compare it.

Again for the shower etc its great. But if you fill the tub or have a sink with no aerator/water saver the flow rate is higher and the water only gets warm. That may be typical for any tankless but I dont know for sure. The big advantage is never running out of hot water in the shower. Back to back showers are no problem.
 
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