[Cheerwino]

Our house has two Microtherm electric on demand "thankless" water warmers. Both have been replaced due to plastic tank leaks (one has been replaced twice) in the five years we've owned them (they're probably eight years old now). Thankfully, they were covered by combination of home warranty and manufacturer warranty. But, we still went months without hot water while the warranties were in contention. 

Once it leaks, the water shorts out all the microchip controllers and basically the whole unit needs to be replaced. The installers I talked to said to avoid tankless electrics and stick with tankless gas. We decided not to retrofit because there was no good place to put a standard hot water heater, although one could have easily been built into the house originally (we weren't the original owners).

I would not recommend Microtherm or an electric on demand water heater. 

[FullRangeMan]

I use one of these below, electric around 6K watts, the filament resistance last two years average and costs same as 5dollars, it provide instant hot water in 3 temperatures.
Of course for winter 120V model are a bit weak, but my house are all 220V, the 220V model are plenty of hot water in the winter.
This device are great value per money, and last for years, the instalation costs are none.

http://www.lorenzetti.com.br/portal_duchas.asp

[ArthurDent]

I use one of these below, electric around 6K watts, the filament resistance last two years average and costs same as 5dollars, it provide instant hot water in 3 temperatures.
Of course for winter 120V model are a bit weak, but my house are all 220V, the 220V model are plenty of hot water in the winter.
This device are great value per money, and last for years, the instalation costs are none.

http://www.lorenzetti.com.br/portal_duchas.asp

Intriguing approach to the issue FULLRANGEMAN. Will have to search for US distributors, and info as I'm unable to translate. Have you always had this unit(s), or do you have cost comparison experience verses a standard tank type heater ?   

[djbnh]

having hot water baseboard heat (oil fired boiler) the domestic hot water coil is incorporated within. IMO, it works superb and it's one less item (hot water tank) that I have to deal with. I'm on well water and my original coil and boiler (builders grade) lasted almost thirty years.

We have the same set up @ my house. Plenty of hot water.

[JLM]

Using the home heating boiler for hot water is a low up front cost, but wouldn't running the big boiler in the summer be very inefficient?

[JLM]

Love the idea of the Lorenzetti, but it could be a real mess to retrofit.  In my five year old house (with 200 amp service and all 12 gauge/20 amp circuits) we may have enough circuit capacity, but to run wiring to 13 fixtures would be major.

And I rather like having a (power vented propane) heating source in our finished basement here in the great white north.

[twitch54]

but wouldn't running the big boiler in the summer be very inefficient?

Not at all, on average it consumes about 12-15 gallons of htg oil per month to heat the domestic hot water. FWIW, my wife and I are 'mty nesters'

[FullRangeMan]

Intriguing approach to the issue FULLRANGEMAN. Will have to search for US distributors, and info as I'm unable to translate. Have you always had this unit(s), or do you have cost comparison experience verses a standard tank type heater ?   

Dear Arthur,
I will translate the text for you, If you post here or send me by PM.

I feel there is various US brands of electric showers, or not??  IF are you saying there is no electric shower avaliable in US I am surprised.   The instalation of this shower are fast, no more than 30 minutes, to change the resistance are ever faster, about 5 minutes, no mess, a spare resistance sells for 3 or 4 dollars.

My actual electric shower cost me under ten(10) dollars and are 16 years old already. Seems to me a small gas heater price starts at 600 dollars here, only the heater machine. 
The special hot water copper tubes, and instalation costs are ever more expensives, and the quality of the service may not be great, as are need to hired people to install all this things.
Regards, Gustavo

[Bill@LakeGeorge]

In the upper right hand corner of the posted website there is a link to english.

[ArthurDent]

Dear Arthur,
I will translate the text for you, If you post here or send me by PM.

I feel there is various US brands of electric showers, or not??  IF are you saying there is no electric shower avaliable in US I am surprised.   The instalation of this shower are fast, no more than 30 minutes, to change the resistance are ever faster, about 5 minutes, no mess, a spare resistance sells for 3 or 4 dollars.

My actual electric shower cost me under ten(10) dollars and are 16 years old already. Seems to me a small gas heater price starts at 600 dollars here, only the heater machine. 
The special hot water copper tubes, and instalation costs are ever more expensives, and the quality of the service may not be great, as are need to hired people to install all this things.
Regards, Gustavo

In the upper right hand corner of the posted website there is a link to english.

Thanks, and Thanks, FRM - Bill. I missed it. As to what might be available domestically in that category I don't have a clue. Till you noted it, I'd never seen or heard of that approach. I'm happy, with the tankless at this point, but should I win the lottery down the road it's something I'd consider in a new location/home.

[FullRangeMan]

Love the idea of the Lorenzetti, but it could be a real mess to retrofit.  In my five year old house (with 200 amp service and all 12 gauge/20 amp circuits) we may have enough circuit capacity, but to run wiring to 13 fixtures would be major.

And I rather like having a (power vented propane) heating source in our finished basement here in the great white north.

Thanks for the English link info. here it is: http://www.lorenzetti.com.br/site_in/portal_duchas.asp

Dear JLM:
This kind of electric shower works fine with a gas shower or even boiler/tank, then retrofit is not mandatory.

And it is a very safe system, no electric shock.  IF the house do not have a electric ground, just use the last part of the water tube in plastic tube (the water tube between the wall and the shower).

For this electric shower I use a 50 amp circuit breaker. Electric showers are perfect for me, I do not see any prob, low price, fast to repair, new models every year if the lady house fells this one are ugly.
Many houses use both systems here, electric and gas, if the gas tank empty, use the electric.
Regards, Gustavo

[Bizarroterl]

We have a Bosch tankless I installed 10+ years ago.

Disadvantages: 
    Takes a little longer for hot water.  The difference is that the tankless requires a little time to heat up its heat exchanger.
    The model we have doesn't have a thermostatically controlled output.  It raises the water temp by an adjustable amount.  Since the incoming water temp changes from summer to winter I have to adjust the output twice a year.

Advantages:
    Less energy (gas) use.
    Unlimited hot water.
    Takes up less room.
    Did I mention unlimited hot water?


  The issues others have mentioned about a tankless not being a good choice in northern climates isn't a problem with tankless heaters.  Tankless heaters are designed to heat up a certain amount of water a certain amount.  If anyone ends up with a tankless that doesn't heat up water properly, the installer goofed and installed the wrong size unit.
  Manufacturers sell these in several different sizes and picking one too large wastes money and too small won't heat water enough.  Installers that aren't familiar with tankless heaters are used to 1 spec - how many gallons?  With a tankless you need to know the temp of the incoming water in winter, how many GPM will be pulled (flow rates of shower heads, sinks, dishwashers, washing machines, etc that are run at once), and how hot the outgoing water temp is desired.  Knowing that they then have to translate that into BTU capacity and select the correct system.  No wonder there have been a lot of unhappy users.   


  On my project list is to add solar HW collectors/tank to preheat our incoming water and maybe replacement of the Bosch with a Navien condensing tankless heater.   

[TooManyToys]

Just read through this thread and I'm not trying to be a smartass here, but ..... I guess you didn't get it inspected either.

It appears you have a ground wire attached to one or both plastic water pipes.  That won't work.  All grounding has to be on a metallic pipe that is continuous to earth for conductivity, or wired to the exterior grounding rod by the electrical meter.

If you don't want to be inconvenienced, a tankless is probably not for you. 

My tankless cost me about $600 a few years ago, and I did the installation -- I am no plumber. 

I hung it on the wall (~20 lbs.?), extended the gas line that was in place for the heater it replaced (screw fittings), added a few feet of copper pipe to connect with the existing inflow and outflow pipes, and enlarged the roof vent from 4" to 6" to handle the larger pipe (double walled spec'd). 

The unit I have requires no electricity at all; it has a wee turbine that creates the spark to fire the burners. 

Seems that electric units make the most sense only when located at the point of use, say under a sink, where you only need small amounts of hot water.  To run a whole house unit, we want fire and want it now. 

[Peter J]

Just read through this thread and I'm not trying to be a smartass here, but ..... I guess you didn't get it inspected either.

It appears you have a ground wire attached to one or both plastic water pipes.  That won't work.  All grounding has to be on a metallic pipe that is continuous to earth for conductivity, or wired to the exterior grounding rod by the electrical meter.

I think you're looking at copper that's painted white. It may indeed provide a ground path. While commonplace many years ago, grounding to water pipes is no longer allowed by most codes, primarily because of the possibility that the pipe could be compromised somehow. On the other hand, if one is certain of the pipe's integrity and connection to earth, it can be viable.

[Steidl Guitars]

Peter is correct, that's copper that's been painted.  The ground wire was stuck there by an electrician when he changed the main panel on my house, and has nothing to do with the water heater itself.

That said, thanks for bringing it up just in case. 

[ctviggen]

That grounding may be to ground the two copper pipes together, not to provide a house ground.  I've done the exact same thing for my soft water system (that is, used a copper wire to ground the two copper pipes entering and leaving the soft water system otherwise, the copper piping after the soft water system wouldn't be grounded).  And my house ground is at the meter entrance and directly into the ground.

The NEC still (at least as of 2005, though I haven't checked the 2008 codes) still  allowed grounding to piping entering the home.  There were certain conditions on it, though, to avoid loss of ground.

[Steidl Guitars]

That grounding may be to ground the two copper pipes together, not to provide a house ground.

That is correct; the ground wire in the photo is about 10" long and is only connected to those two pipes. 

Question.  Is that intended to increase the amount of surface area available to dissipate a ground fault of some type? 

[TerryO]

I don't know if this will change anyone's mind, but I've served as a County Water Commissioner for over 19 years and the studies that we've seen indicate that the majority of water usage, that the customer gets billed for, is related to letting the water run until it gets hot. Some of the smaller units can be installed under a kitchen counter and will give nearly instant hot water. It can be cost effective, depending on how much your local rates are.

FWIW, a couple of my fellow Commisioners have recently installed them.

Best Regards,
Terry Olson

[Peter J]

That grounding may be to ground the two copper pipes together, not to provide a house ground.  I've done the exact same thing for my soft water system (that is, used a copper wire to ground the two copper pipes entering and leaving the soft water system otherwise, the copper piping after the soft water system wouldn't be grounded).  And my house ground is at the meter entrance and directly into the ground.

The NEC still (at least as of 2005, though I haven't checked the 2008 codes) still  allowed grounding to piping entering the home.  There were certain conditions on it, though, to avoid loss of ground.

Way off topic, but can you elaborate on this for me? I'm not understanding why your plumbing needs to be grounded at all if the ground stake is providing ground to panel and subesequently the house. It seems to me that at the least it would be  redundant, and possibly be a hazard.

[TooManyToys]

Sorry guys - just being cautious, not a PITA.  It just looked like PVC and warning flags went up as I've seen homeowners do that before.

I think you're looking at copper that's painted white. It may indeed provide a ground path. While commonplace many years ago, grounding to water pipes is no longer allowed by most codes, primarily because of the possibility that the pipe could be compromised somehow. On the other hand, if one is certain of the pipe's integrity and connection to earth, it can be viable.

Peter is correct, that's copper that's been painted.  The ground wire was stuck there by an electrician when he changed the main panel on my house, and has nothing to do with the water heater itself.

That said, thanks for bringing it up just in case.