Tankess water heater

[CAGE-RATTLER]

With the big fluctuations and instability of gas prices these days .......... i would think electric would be the way to go.

And since these units only heat when the hot water is turned on .......... i would definately think they would be more efficient than a hot water tank thats kicking on and off all day and night to maintain the temps.

Flow rates is what would concearn me as i have extremely high water pressure in my home compared to my neighbors.

Another thing i wondered about is how the water comes out as soon as you turn the hot water on?

Does it come out cold at 1st then heat up gradually ................ or does the unit not allow water to comeout till the water is heated and come out slowly and then flow faster as the unit catches up?

[Riche_guy]

Electric hot water tanks do not come on and off all day unless they are kept in cold areas or are constantly being used. I use to think that before I got a new 60 gallon one guaranteed for 12 years with led lights on the outside to indicate when the elements were functioning. I got it at Home Depot and during the course of the day it may come on twice.

[jeep]

I am going to measure my vent later on but he told me that for sure my house vent would be three inches, not enough to handle the amount of heat of the combustion in the tankless heater.
Oh Well..

roberto.

Roberto, yes your current water heater vents to a 3" vent, but in most cases they tie into your furnace vent which is 5". If yours is typical then you can save quite a bit of money by simply hooking the new one into the furnace vent...

[CAGE-RATTLER]

Electric hot water tanks do not come on and off all day unless they are kept in cold areas or are constantly being used. I use to think that before I got a new 60 gallon one guaranteed for 12 years with led lights on the outside to indicate when the elements were functioning. I got it at Home Depot and during the course of the day it may come on twice.

I was referring to going from a gas hot water tank to an electric tankless heater.

But i guess either one would be determined by how old the unit is and how well insulated it is.

Mine is gas and pretty old and i really dont know how often it kicks on but would assume it kicks in whenever the temp drops below a certain setting. Now that i think about it ......... i'll have to check to see if thats adjustable (how low the temp drops before kicking back in).

[Riche_guy]

I was referring to going from a gas hot water tank to an electric tankless heater.

But i guess either one would be determined by how old the unit is and how well insulated it is.

Mine is gas and pretty old and i really dont know how often it kicks on but would assume it kicks in whenever the temp drops below a certain setting. Now that i think about it ......... i'll have to check to see if thats adjustable (how low the temp drops before kicking back in).

I guess you keep your tank where it is cool. I know for electric tanks you can insulate the outside. They sale these cozy jackets. Not sure with gaz you can do the same.

[mench]

My tankless is vented above the furnace..Yes the water is cold at first then heats up...my unit has the electronic ignition....it only fires up when hot water is called for.....I went for the smaller model because the girls are all married and let thier new husbands pay for thier long showers...The bride still works so when I change water I am the only one home so running out of water in not an issue...yes you do have to have at least an 1/2 in gas line to the unit.If you have a place on an outside wall it can be vented outside.
Mine has worked just fine for the 1 1/2 yrs we have had it.

Mench

[discussmith]

If you have gas then you should use it. Electricity is the most inefficient means of producing heat. Depending on mineral content electrical units can have a lot of maintenance as deposits constantly build up on the elements causing them to fail. Many utilities use natural gas to generate electricity so you will not the escape higher cost of gas.

[Discus_Josh]

DiscusSmith is absolutely correct. Going to an electric tankless heater is not the answer as many of the "whole house" models produce ~3gpm and use 330v, which 99.9% of the homes are not equipped with. and yes electricity is the MOST ineffiecent way to heat water.

On another note, it appears that the US govt will give you a $300 credit on your 2006 taxes by going to a heater that is above 84% effiency. You can find the info on the IRS website for more details.

HTH

Josh

[korbi_doc]

Ok guys, my new house is all electric & I have been planning to get one of these tankless heaters with the computer to control the temp... so... why can't I use propane? I have seen them set up for propane on the sites.. Will need to install a small tank, but how much would it use if just for water with 1 person living in the house (+ dog & fish of course)? Originally thought I would put in a propane fireplace, but have shelved that one for now... any ideas? Dottie

[discussmith]

Your propane distributor can supply you with usage requirements for ave. households with "X" number of gas appliances. They can also give you suggestions of how big and where to place the tank. They can give you projected cost estimates of gas for the near future and the best purchase plan for your situation. Of course they are in the market to sell gas so keep that in mind as well. Meaning they will paint as pretty a picture as possible.

[CAGE-RATTLER]

I guess you keep your tank where it is cool. I know for electric tanks you can insulate the outside. They sale these cozy jackets. Not sure with gaz you can do the same.

My hot water heater is in my kitchen (dont have a basement) and the house is kept at 70 degrees year round.

When the water is heated to 120+ degrees by fire or electric ........... and then that is taken away once it reaches the right temp ................ i dont care how many jackets you put on there ............ the water is going to start cooling off and then it will be reheated again once it reaches a certain temp by kicking on and off during the day and night.

A tankless heater that only runs when the hot water is turned on ............ has to be more efficient IMO!!

[Riche_guy]

My hot water heater is in my kitchen (dont have a basement) and the house is kept at 70 degrees year round.

When the water is heated to 120+ degrees by fire or electric ........... and then that is taken away once it reaches the right temp ................ i dont care how many jackets you put on there ............ the water is going to start cooling off and then it will be reheated again once it reaches a certain temp by kicking on and off during the day and night.

A tankless heater that only runs when the hot water is turned on ............ has to be more efficient IMO!!

Insulating a hot water tank that is in the cold will help no matter what. The jacket will slow down the cooling of the tank and I do mean slow down, not stop. this way the elements will not come on as often. Money saved.

As far as the efficiency of a tankless heater, I don't think it is so cut and dry. When heating they take a lot of energy. If they were very efficient compared to water tanks, all new construction would have them and you would hear more about them. For some reason there is not a lot of studies proving their efficiency except from the companies selling them. Perhaps water tank companies are so strong that they are killing the tankless system.

[CAGE-RATTLER]

An electric car doesnt pollute as much as a gas driven car either ............. but did they stop making gas powerd vehicles?

Just seems like common sense to me that heating on demand is more efficient than constant heating. How often is that hot water tank coming on when your on vacation compared to a tanless system?

With tankless .......... you wouldnt even need the water heated as high. You could set it to your desired shower temp and just run the hot water only ............ or set it to whatever you keep your fish tanks if your using it just for that.

But ............. To each his own!

[Riche_guy]

An electric car doesnt pollute as much as a gas driven car either ............. but did they stop making gas powerd vehicles?

Just seems like common sense to me that heating on demand is more efficient than constant heating. How often is that hot water tank coming on when your on vacation compared to a tanless system?

With tankless .......... you wouldnt even need the water heated as high. You could set it to your desired shower temp and just run the hot water only ............ or set it to whatever you keep your fish tanks if your using it just for that.

But ............. To each his own!

I too was thinking about the car analogy. I wouldn't say that a tank heats constantly though. It is more on and off sort of speaking. Don't get me wrong. I like the idea of the tankless system. I just wish there was more independant documentation. I'm not sure why there isn't any.

[tpl*co]

WOW! A tax rebate? Is there a deadline to get in on that? I'm seriously considering a unit too since my house's water heater can't handle one side of the house with the washers and the showers on it (my house has 2 tank water heaters on either end of the house). I can't fill up the tub without it going cold . Right now my total gas bill is for the water heaters (we went to a wood pellet stove to heat the house, BIG SAVINGS!) and it is running around $40 a month to run both water heaters. I wonder what the savings would be if I went tankless? (would probably do the one first, both sides of the house are on individual plumbing lines ).

Tina