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Anthona 12-01-2005 07:26 AM

Instant hot water tanks
Watched this show on tv about these hot water instant tanks. Its really complicated after reading the companys info sheet. There are so many variables and possible dangers of carbon monoxide. Has anyone used these and really recommend them? I have a 75 gal gas hot water heater now and its almost 18 years old and to my knowledge in very good condition. The problem is that i have to run the water to get hot to do all chores that need hot water. I'm constantly filling up bottles so as not to waste the cool water till it gets hot and use it on my plants. Is it cost worthy? Also, the differences of these tanks and what I read about hot water pumps that u add to your regular hot water tank. From what i understood, that along with those pumps, one has to add a gizmo to each outflow where u want the hot water ie kitchen sink, dishwasher, shower.Of the 2 which would be safer and cost effective? Thanks for any feedback. :)

BillsCatz 12-03-2005 03:29 PM

Instant HWH
Fist of all, your current hot water heater had lived well beyond it's normal lifetime -- be prepared to replace it soon. There are two types of so-called 'instant' hot water heaters. One is "point of use," which is installed right near where it's used -- isn't always practical. The other is "tanlkless," which actually heats the water as it's used and doesn't have a storage tank.

Which would suit your needs depends on many factors -- type of fuel (gas or electric), how many fixtures (sinks, tubs, showers, washing machine) and how many of those get used at the same time. The main limitation of tankless HWH is gallons-per-minute -- the combined use of hot water by all fixtures can't exceed the GPM output of the heater. In other words, no shower while filling the washing machine, or no dishwasher and sink running while washing the clothes.

The point-of-use, as it's name implies, is located near whatever it's supposed to supply. This doesn't always work for most people, but they will provide a constant flow of hot water to the desired fixture.

Those are the basics, I hope this helps. Another option might be two separate 40 gallon HWH, each supplying parts of your system.

Rocky 12-03-2005 05:23 PM

Here's a manufacturer of tankless water heaters. Their relatively reasonable but installation can get pricey due to the proprietary ducting system for exhaust and combustion air. They're gas fired.
Another solution to getting the hot water where it is needed without running the water for long periods of time is a recirculating system. This system involves a small pump that recirculates the water back to the water heater tank until the hot water has reached the point of use. It's most common to put the recirculating pump at the sink furthest away from the water heater tank.
A 75 gallon tank would suggest you live in a rather large home, if not you may be heating way more water than you need. I agree with Bill, you're water heater is well beyond it's useful life. Good Luck.


Backroad boxer 12-04-2005 08:38 AM

Looking for electric instant Hot water
I am putting a bathroom w/ a shower stall in my shop. This will be an infrequenly used shower, but I want to be able to have hot water when I need it. I have been toying with idea of having a instant HW system or a small water heater. Since I would like to stay all electric, the gas fired system is out. Also, the idea of keeping the small tank heated while im not using it seams to be a waste.

Rocky 12-04-2005 09:47 AM

I have seen electric tankless water systems mainly used for sinks. It's a tall order to get enough gallons per minute out of one for a shower.


powrofone 12-04-2005 10:07 AM

Electric Tankless
There are whole house tankless hot water heaters available.
They are a bit pricey and require large electric feeds to operate. The electric work required to install them usually negates any of thier advantages. I have done several estimates to install the necessary electric to operate the whole house tankless heaters and all but one would also require a electric service upgrade to install them. They are really more suited to new home installations where all the sub systems necessary can be calibrated and installed as required.
Why not install a small tank style electric heater?

Backroad boxer 12-04-2005 04:05 PM

Small tank water heater
I am looking to compair the difference in price, instalation and continuous amp draw between the inline heaters and a small tank. Just started getting information.

BillsCatz 12-04-2005 08:17 PM

Takagi HWH
Takagi makes tankless hotwater heaters in both gas and electirc, relaible with a good warranty.

Rocky 12-05-2005 09:23 PM

I installed a tankless water heater today. It's a 240 volt 9500 watt water heater that will produce 2 gpm at a 27 degree temperature rise. This means you will get 2 gallons of water per minute that will be 27 degrees hotter than what is was before it got heated. This unit draws 40 amps.


2pyrs 12-14-2005 05:06 AM

In other words, no shower while filling the washing machine, or no dishwasher and sink running while washing the clothes.

This is wrong with the newer units sold today that can run more then one area, but as said price high. If you are looking for a nice shower then you may want to consider a unit just for it and still use tank for the rest of the house, you may be able to down size your now tank. As to cost to run tank less unit you have to look at your over all consumption, keeping in mind the tank-less unit only runs when used unlike tank unit that has to come on to maintain itís level of warmth even when not used. Installation is not that hard with some units but it can get complicated if you chose one of the oneís that is computer ran and have to do a whole new set up, exhaust, water line, gas, electric. As with any gas run unit there has to be safety taken in consideration at all times so unless you feel comfortable DIY I would recommend having a pro do the work. Cost could be as little as $1,000 to $2,000 depending on the unit and installation.
Youíre now unit is up there in years but I have seen them older when maintained. If waste of water is your concern you might want to consider one of the units sold for recirculation of the cold water back to your tank. They just had a show on TV with Ed the plumber showing the different types sold and how to install some of them.


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