tankless water-heater

Behold. (Photo by the so-called “old guy” with the dreaded and utterly reprehensible Nikon D100 with flash.)

We had a tankless water-heater (pictured above) installed yesterday (Monday, October 13, 2008), replacing our old tank-type water-heater which was around 10 years old.
A typical tank-type water-heater, what is usually seen in this nation, has a 40 or 60-gallon or maybe even 80 or 100-gallon retention tank heated by a cooker underneath, usually a natural-gas burner or an electric element.
The water inside the tank is heated to maybe 140° (whatever ya set it at), and if the temperature of that water falls, a thermostat triggers the cooker.
Turn on the shower or the washing-machine, and preheated water flows out of the tank, replaced by cold input, which is then heated.
Typically, the cooker can’t keep up with hot-water demand, so your shower goes cold.
Colder water flows from the tank to the shower. I couldn’t take a shower and run the washer together.
A tankless water-heater heats water on demand — there’s no retention tank.
As water flows, cold comes in one side, gets heated as it flows through, and comes out hot.
The tankless only heats water as it’s used.

Our house originally had a tankless water-heater, but it was manufactured in Sweden, and no one would work on it (except me).
It also had a live pilot (as opposed to electronic), but it would blow out if windy.
Relighting it was a struggle, but I often did.
The domestic hot-water also circulated through a heater-core a blower blew through, so it was also heating the house.
The entire system was part of superinsulated house design, where a house with little heat-load could be heated by the water-heater.
It worked fine, except —A) constantly if below zero outside, and —B) no one would work on it except me.
A stroke also intervened, and the pilot blew out the same day.
Linda returned from the hospital to a cold house, and had to struggle to relight the pilot herself.
Finally the heater-core in the water-heater corroded, and we were getting replacements parts from Floridy via UPS — not locally.
But no one would install that core for us, and our heating-contractor said heating our house with domestic hot-water was non-code in our area.
So out came our entire fancy-dan Vent-Air® system, including our original tankless water-heater.
We replaced it all with a small furnace, a forced-draft tank-type water-heater, and forced-air ventilation with an air-to-air heat-exchanger.
The Vent-Air® was mainly an air-to-air heat-exchanger, but had that added hot-water heater core and blower.
Code required two separated water-heaters to heat hot water: —1) our domestic hot-water, and —2) for the house heat.
We decided a furnace was more standard; enough for the average heating-contractor to work on.
Don’t know as this was a wise move.
The house is more humid than it was with the Vent-Air®. My guess is the furnace is pumping condensation off its heat-exchanger.
We also have to have electricity. Both the furnace and the forced-draft tank-type water-heater have electrical inputs; the water-heater a small electrical draft-inducer blower. Both also have electric pilots.
If the power went, the Vent-Air® blowers were incapacitated, but we still had hot water. The original tankless used no electricity.
This is part of the reason we installed the stand-by generator; to push the furnace and the water-heater if the power went. (It also pushes the freezers.)
Sure; put in a dehumidifier. With the Vent-Air® we didn’t need one.
So now tankless water-heaters are becoming more accepted — not future, like our original unit.
Our gas-supplier will rebate a tankless installation; 400 smackaroos.
They’re encouraging tankless, since they ain’t using the gas needed to maintain a tank of hot-water. —I always thought maintaining a tank of hot-water during our trips to Altoony was silly; used to turn the water-heater off. So too trips to Floridy or Delaware.
The heating-contractor that maintains our stand-by generator was pushing tankless, and our forced-draft tank-type water-heater was old enough to be suspect.
I wanted to replace it before it sprang a leak.
So back to tankless — seemed more energy-efficient anyway.

I should add that we also had installed a separate recirculator pipe-run to keep the water in the long run to the kitchen hot.
That run was so long it took about a minute before hot water flowed; so a recirculator run was added to recirculate the water standing in that run back through the water-heater. If the water therein drops below 120°, a pump (at left) recirculates the water therein back through the water-heater until that standing water is back up to 120°. That way we don’t have to run the water a minute before using the dishwasher.
The pump is also on a timer, so it’s off from 11 p.m. until 6 a.m.
I could have added recirculator runs to other outlets (both bathrooms), but didn’t bother. We don’t use water there much, and get hot water in less than 30 seconds.

RE: “‘Old guy’ with the dreaded and utterly reprehensible Nikon D100.......” —My macho, blowhard brother-from-Boston, who is 13 years younger than me, calls me “the old guy” as a put-down (I also am the oldest). I also am loudly excoriated by all my siblings for preferring a professional camera (like the Nikon D100) instead of a point-and-shoot. This is because I long ago sold photos to nationally published magazines.

We designed our house here in West Bloomfield to be ultra energy efficient. It is super-insulated, enough to have a low heat-need. It was built for us in 1989; and we still live here.

I had a stroke October 26, 1993.

“Linda” is my wife of 40+ years.

“Domestic hot-water” is the house-water used in cooking and cleaning.

Our house is so tight it needs “forced-air ventilation.” An “air-to-air heat-exchanger” tempers the incoming outside air with the outgoing inside air. (There is no air mixing.)

A “stand-by generator” generates electricity when the power fails, which is fairly often out here in the country. Our “stand-by” is a one-liter V-twin engine powered by natural gas. It kicks on automatically when the power fails.

“Altoony” (Altoona, Pennsylvania) is the location of the “mighty Curve” (“Horseshoe Curve”), by far the BEST railfan spot I have ever been to. Horseshoe Curve is a national historic site. It was a trick used by the Pennsylvania Railroad to get over the Allegheny mountains without steep grades. Horseshoe Curve was opened in 1854, and is still in use. (I am a railfan, and have been since I was a child. —I’ve been there hundreds of times.)

My wife’s mother lives in central Florida, and I have a younger brother and his family that live in northern Delaware.