NG on demand water heater

[tallyho8]

The thing we have to remember with these, they aren't new items. They've been using them in Europe for 20+ years.

Yes they have been around for a long time. I had one that came in a rental house that was built in 1930. It was mainly copper and in 1985 it was in excellent shape and worked perfect. I loved it.

I rented the house to a man who had never seen one before. He lit the pilot and couldn't figure out why the burner wouldn't light. He didn't turn the water on to test it or it would have lit.

The next month when he paid rent he tried to get me to take some money off the rent because he threw that "old hunk of junk" away and installed a new 20 gallon water heater.

 

[Sigarms]

does anyone have a natural gas on demand water heater? i am trying to find out how loud they are? i noticed they sell models for outside installation, which might be an option if they are too loud.
heehaw

Don't own one yet, but been certified from a couple of manufacturers. The noise really isn't an issue. The reason why they have "outdoor" units is due to space constraints and venting on the interior of the house.

Funny, when those units first hit big in the U.S, they were first called instantaneous water heaters, becuase they powered up when the demand was called for and heated the water "instantly". Only problem was that the consumer thought it meant they got hot water at the point of use instantly. That's why they are now refered to as "continuous" hot water heaters

For "instant" hot water, there are numerous pumps/systems out to bring water to the point of use at a moments notice. Most of these manufacturers are going to be trying to weasle their way into laws down the road. Figure if you're on city water, and one pump system can save the average homeowner thousands of gallons of water a year, mulitply that by a city population and particularly in the hot regions of the country where water can become scarce, well, it's only a matter of time before laws get enacted. Hate to say it, but it makes sense, it's only a question of who's going to get to the gold mine first.

Downside to these water heaters is if you're on well water, better make sure you check and clean the heat exchanger of the water heater annually. Scale and residue could build up fast, and if not taken care of properly, could cause some issues.

By the way, they may or may not save you money on your gas bill. Numerous factors come into play.

 

[heehaw]

another twist: i see some units are for mounting outside: they don't have the vent mount on the top: outside??? could that mean under the house or in the attic?? or if you mounted the unit on the outside wall, seems like it would be a chore to keep them from freezing?
heehaw

 

[kenmac]

another twist: i see some units are for mounting outside: they don't have the vent mount on the top: outside??? could that mean under the house or in the attic?? or if you mounted the unit on the outside wall, seems like it would be a chore to keep them from freezing?
heehaw

No they don't have a vent pipe or stack.. You have to insulate the pipes well

 

[heehaw]

if you could put the unit under the house, the freeze problem would be solved, plus maybe put it closer to where the most hot water usage is??
heehaw

 

[kenmac]

Yes, you can put them under the house / attic.. The vented type...Vent through wall.. Attic install vents through roof

 

[heehaw]

i mean the ventless type: why couldn't they be put in the attic or under the house?
heehaw

 

[kenmac]

There are no ventless . They all are vented.. Just in different ways

 

[jinjimbob]

You can get an electric one instead, but they take 2 or 3 x 220v circuits, around 90 Amps.

If you have a family sized 4+, you really won't save any money on fuel, it just means that you'll always have hot water.
These are very good though to use in a holiday house that you hardly goto.

 

[J_J]

For those that are interested, they make a system to keep hot water at your spigots and showers. They make out that it is a really big deal, and the price is kind of high. In reality, it is a simple system that recirculates the hot water to wherever. It works like this, Once hooked up and plugged in, it begins to circulate hot water from tank to the sink or shower. It is set to come on when the temp is below your set temp. Is it efficient, the answer is no, because it keeps hot water in the lines, and most pipes are not insulated. However, if you designed your house from the ground up, and took the insulated pipes into consideration, then you would realize the benefit of instant hot water. That is assuming that your hot water tank is operating correctly. If you go one step further, you could have a light, or digital thermometer to indicate that you have hot water available. It would only take a small pump to recirculate your water to the set temp, maybe a few minutes. You hook up the system by cutting the hot water line at the sink, and the hot water line from the tank goes to the input of the pump, using a tee. The outlet of the of the pump goes to the cold water pipe using a tee.

If you had say three bathrooms, three pumps might get expensive, so a solenoid could be installed at the water exit point, with a set temp device. This way, a single pump back at the water heater could keep the whole house supplied with instant hot water.

Anyway, just rambling. DLAF.