[Greenbuilding] [BULK] Tankless HW and hard water

[Dr. C.F. Vasile]

Keith: The tankless I own has 3 copper heat chambers and 3 commercial 
heating elements; an Acutemp Model C-150. The elements expand & contract to 
loosen lime deposits that are continually flushed away. I too had my doubts, 
so I bought 3 element for back-up. They're still in the box. Carmine

----- Original Message ----- 
From: "Keith Winston" <keith at earthsunenergy.com>
To: "Greenbuilder list" <greenbuilding at listserv.repp.org>
Sent: Wednesday, September 06, 2006 1:43 PM
Subject: Re: [Greenbuilding] [BULK] Tankless HW and hard water


> It's not obvious to me why this would be so. Anyone care to share
> thoughts? Lime formation won't tend to happen below, I think, about
> 160F. But surely in a tankless there are hot spots that exceed that?
> Maybe that's the answer right there? Or perhaps it doesn't form well in
> a stainless steel environment...
>
> Keith
>
>
> Dr. C.F. Vasile wrote:
>> Yes. I've been heating my house and water with a 15 kW Tankless electric
>> heater since 1996. I live in Patchogue, NY where cold water temperatures
>> drop below 45F in January. We have very hard water and have had no 
>> problem
>> with calcification. In contrast, the tankless coil in our obsolete oil
>> burner used to "lime-up" in 6 months or so. When it did, its 1.5 gallon 
>> per
>> hour firing rate (oil) couldn't sustain a low flow shower and its
>> water-heating efficiency dropped below 25%.