I've gone tankless.

Sweet!

Funny enough, the first time I got to use a system like that was on the remote penninsula of Ayacara in southern Chile. The house didn't even have a fridge and used a wood burning stove to cook food yet it had an on demand water heater. :lol:

 

<div class='quotetop'>QUOTE(Godiva @ Nov 24 2007, 01:48 PM) [snapback]543682[/snapback]</div>

There are other companys out there other than Noritiz. Takagi, Rinnai, Bosch and Paloma. I have had very good luck with Paloma's and Rinnai's. Not so good with the Bosch. (I have great respect fot the Rinnai space heaters however).

I have been tankless for years. My cabin has a standing pilot Paloma, my house a Takagi Tkjr. Never want for hot water. Be advised that the venting for most demand water heaters can be and is very expensive, often rivaling the cost of the unit. Most have to vent through a stainless steel system rather than the aluminum "B" type vent common to most water heaters. The exception is the Paloma legacy standing pilot light series.

It is a no brainer and I wish more people would figure it out!

 

let us know how you like it once you get to put a little demand on it. some day we're gonna use all the stuff we learned from folks just like you to do our own house!

 

<div class='quotetop'>QUOTE(galaxee @ Nov 24 2007, 06:03 PM) [snapback]543763[/snapback]</div>

The unit in Chile performed perfectly. We had 8 people taking showers one after the other and nary a complaint.

 

<div class='quotetop'>QUOTE(F8L @ Nov 24 2007, 09:09 PM) [snapback]543766[/snapback]</div>

that's quite impressive. at night our solar tank would probably run out well before the 8th shower. i do really like solar hot water during the day though.

 

The original hot water tank in my house was connected to a water jacket inside the half-electric half-wood-burning stove in the kitchen. First you built a fire, then you cooked breakfast, and then you hopped in the shower while the water was still warm. The monster boiler in the basement was fed from an entire room full of coal, and the heat eventually rose to the upstairs radiators. Of course, the coal was gone by the time it did, and you'd have to get out of bed and shovel in some more. I never saw the original clothes washer, but maybe that's why the path down to the river was so well worn. :lol:

 

I put in a Takagi 3 years ago and still don't understand why the tank continues to be the standard when tankless has so many advantages: more energy efficient (and thus cheaper to operate), limitless hot water, smaller installation footprint, reduced earthquake hazard, etc. Is it the expense? Then why is it more of a standard in the 3rd world?(which I have heard from several sources now seems to be the case).

One oddity I had to get used to was a few seconds of cold flow each time the flash heater starts up again, such as in the kitchen, turning the hot tap on and off during food prep or washing up. With a tank, once the hot water has warmed the pipes intermittent demand always delivers hot water; but with the flash heater intermittent demand always sends a gout of cold water up to surprise the unsuspecting user as it takes a few seconds for the flash heater to get steam up, so to speak. This might be an issue only with taps close to the heater (my flash heater supplies the kitchen less than six feet of copper pipe away) - taps further away will have their water warmed by the hot piping before it reaches them.

Mark Baird
Alameda CA

 

I was intrigued by the tankless sytem and looked into it seriously, but was advised I'd need about three of them. With hot water heat, a new ultra-efficient boiler and a super-insulated tank for the domestic supply was the way to go. And I fixed the rope on the clothes dryer.

 

<div class='quotetop'>QUOTE(airportkid @ Nov 24 2007, 09:16 PM) [snapback]543823[/snapback]</div>

It is more energy efficient to the extent that you don't lose the heat associated with the hot water sitting in the tank. Unfortunately, the savings (of about $5.00 a month) do not make up for the HUGE difference in price of installing the unit (from above: $2700 for tank-less, versus say $800 for a good quality installed 50 gallon water heater).

The secondary advantage is the space required... and I suspect that is a primary motivator in Europe... where flats have very limited space... But that's just my guess.

If you want to argue environmental advantages: well, it sounds like the tank-less unit requires you to waste more water (while you wait for the hot water to arrive)...

I have a home where space is of a premium and I will be replacing my old water heater this spring.... will probably do it myself... At that time, will seriously consider a tank-less unit - but only if it makes reasonable economic sense:

<blockquote>Running through some basic numbers, if a tank water heater is $500, then it looks like a tank-less unit costing no more than a $1000 would be worthwhile. As I am doing my own installation, I am assuming labor costs are zero. </blockquote>

 

<div class='quotetop'>QUOTE(Godiva @ Nov 25 2007, 09:42 AM) [snapback]543947[/snapback]</div>

I am comparing $1000 versus $500 for everything (vents, tubing, rebates, etc.) The only thing excluded is my labor (ok... and the gasoline I spend in my Prius driving around to get most of this stuff.... )

Regarding life expectancy: I only considered the first 10 years of life (beyond that - the NPV value of the benefits are negligible. Besides, I would debate the 3 to 1 replacement ratio. Maybe the tankless unit will last longer, but I won't believe anything over 2 to 1 (and that - I am giving you the benefit of the doubt - my current water heater is 17 years old). Finally, the heat exchanger is the most expensive part of the unit - if that goes bad, you will most likely replace the whole unit.

One interesting point: The pilot in a water heater is not a waste. Its heat goes into the water and therefore is already factored into the value proposition. The only "waste" that a water heater tank has is the heat loss through the tank walls. The delta T is approximately 120 deg F on the inside of the tank minus the average ambient temperature outside the tank (e.g., the closet temperature).

There is one other factor to consider: The heat exchanger in a hot water tank (the pipe that goes up the center of the tank) may not be as effective as the unit in the tankless unit. In fact, one clue that this may be the case is the requirement for a stainless steel flue for a tankless unit, but only a carbon steel flue for a tank unit. The SS requirement indicates that the exhaust temperature is close to 212 deg F and that the water vapor in the exhaust may condense on the inside of the vent; thereby causing corrosion (hence the need for stainless steel). If a tankless unit transfers more heat to the water from the flue gas than a tank unit, then the difference will result in a larger gas savings than the $5.00 I previously attributed.

I have not done that specific part of the analysis yet - I will, when I get closer to making my decision. Just to be clear, if the answer is close - I will tend towards the tankless unit... as I like the secondary benefits it provides (such as space savings and resale value of the home).

 

I prefer a storage heater because there is no loss of water pressure or flow. If a toilet is flushed the reduced pressure affects both hot and cold equally Also a storage heater can more readily be converted to gas boosted solar.

 

We got the same model Noritz as you, about 2 years ago. Originally, we had the next smaller size/demand (takagi) model, which was REALLY all we needed. I calculated our max water pressure demand. But before I could get it installed, my better half just HAD to get involved. A plumber guy ended up selling her the Noritz, and taking the Takagi in trade (shaking head) only not the full amount I paid for it. Oh well, maybe some day we'll have 200 lbs of water pressure so we can take advantage of the Noritz overkill volume that it can theoreticly provide ... but we'll likely never see

We have a huge indoor jacuzzi tub which took 2 hot water tankfulls to fill. Now, we can fill it ... the washing machine, dishwasher, 2 other showers, and still have hot water to spare. Of course, with so many open valves, we'll only be getting a dribble! Lots of hot watter ... but each will only be getting a dribble. I mean my God, who do you know that has 25 gallons / minute of watter volume.

Anywho, did you use double wall stainless vent pipe (at over $100 linear foot) ?

 

I have had tankless ELECTRIC for 23 years now. It has worked perfectly and is much simpler to install than gas units. In the past gas units were cheaper to operate than electric but now the electricity in the Northwest has the advantage in cost. My unit is from
www.eemaxinc.com/ressinglepoint.htm
No venting required. Very small unit. No wasted heat. Much faster initial start of hot water. I installed it myself. Very easy installation.

 

I don't have gas service, so I would have to use an electric system or stick with oil. I'll probably take a tank over the tankless. I have plenty of space in the basement for the tank and wrap it in extra insulation.
It also gives me the option of upgrading it with a heatpump. The increase in maintence will cut into the electric savings, but it will also dehumidify the basement and some models can vent the cold air into the venting system.