tankless water heater??

[tommystinson]

If the choice is gas vs. electric, go with the gas. Residential electric on-demand heaters just can't produce enough heat.To get the capacity of Ken's heater with electricity you would need about 60,000 watts. That would require a 250 amp service at 230v all by itself. Be careful not to confuse efficiency with economy. It's possible to have an electric heater with 99% efficiency. while most tankless/on-demand gas heaters are in the high 80% range. Gas of any type is still a good deal cheaper than electricity, so the gas heater will eventually save you money. The only efficiency increase of an on-demand electric vs. traditional electric heater is the tank loss. If you insulate the hell out of a tank then any "advantage" of an electric on demand is moot. If you have hydronic heat, check out an indirect water heater. It's an insulated tank with a heat exchanger coil inside that runs as a zone off of the boiler. I installed an Amtrol WHS-80 back in March. Continuous output, 70 degree rise, is about 3 gal/minute, but I'm starting with 80 gallons in the tank. We've run the dishwasher and washing machine and four consecutive showers without a problem because of the tank reserve. It's all stainless, inside a plastic shell that's filled with expanded foam. I'll lose 4 degrees over 24 hours if the boiler cuts out. My boiler is 95% efficient, so I'm probably getting 90-92% after the tank loss. Many apartment buildings run indirect fired heaters w/ boilers even if they have forced air heat. Like Ken's setup, it wasn't cheap either. I paid about $2500 all told, and I installed it myself. It has a 10 year warranty (what's there to break? with an effective lifespan of 20-30 years. I would have gone with an on demand heater if I didn't already have a boiler though, FWIW. Sorry for droning on and on...

[Crazcnuk]

Derwat had to replace his hot water heater a couple of years ago. The old one had developed a leak (gas) at the burner.

Instead of throwing away the old heater, he took off the plastic shell, removed the foam insulation and put the shell back on.

Then he installed a new 44gal hot water heater, next to the old one, and plumbed the two tanks in series.

What this does, is the water comes out of the ground at around 50deg, sits in the first, uninsulated tank and gradually warms up to the temperature inside his furnace room (~75-80deg) Then that water is fed into the new hot water heater.

This reduces the amount of energy needed since it only has to heat the prewarmed water, not the stuff right out of the ground.

My hot water heater sits in it's own little closet. It keeps this closet warmer (I insulated the closet), than I keep the trailer, so I built a stand and lifted the heater as high as I could, in it's closet, so that it sits in the warmer upper part of the closet. It's own heat loss helps keep it warm! Dong this also made acces to my bathtub plumbing a lot easier.

[heatmanal]

I built a new house 3 years ago installed (2 ) takagi T-K JR. One on each side of the house. I split the house in half spare bath & laundry on one master bath & kitchen on the other. They will run (2) showers at the same time with a slight decrese in water pressure. If you try to run a garden tub (no shower) it will work with reduced water pressure. When sizeing its about gpm. I should have gotten a bigger unit for the garden tub side or run them in series. The only problems I've had in the winter (Indiana) the backdraft damper iced shut once & sometimes a sink facet wont activate burner. BTW I'm on city water & natural gas. As far as saving money on utilty bills I'm sure it saves some but dont expect cutting bills in half especially if you have a teenage daughter at home. Another thing to consider is gas pipe sizeing gas units start at 140,000btu the average furnace 100,000btu ALLEN

[fredintoon]

"dont expect cutting bills in half especially if you have a teenage daughter at home."

Hi Al,
Oh yes. I have no idea what it is that teenage girls do in bathrooms but it takes forever and uses all the hot water.
There was one thing I did find out, both my girls were in our (one & only) bathroom for over an hour with the shower running and the door half open. So I knocked & looked in and there they stood fully dressed with their hair all wet and the shower blasting our expensive electrically heated water down the drain. It seems they were raising the humidity the better to hot oil their hair.

[tommystinson]

No need for a teenage daughter in my case. My wife, in every respect BUT her showers, is "low maintenance". She's CUT BACK to 20 minutes. That does not include leg shaving. Then she uses a half full tub after her shower, followed by a quick shower rinse-off!
I'm not sure why, but our water service is provided bu 1 1/4 copper. Out of our closest sink I can pull 17 gallons a minute. It's actually scary to see.