# tankless water heaters



## bustindeer (Aug 23, 2006)

I was just wanting to know if anyone has purchased a tankless water heater and if so, how efficent are they?  I have noticed on alot of the sites I went to, say 1 shower or 2 sinks per heater.  I need a little more I think, but in a way it may work for the whole house providing everything isn't going at the same time.  

Any input would be greatly appeciated


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## Slug-Gunner (Aug 27, 2006)

*Tankless/On-Demand Water Heaters*

This style of "On-Demand" water heater is quite popular in Asian countries and in Europe. I had one in an apartment I was living in for almost 2 yrs while stationed in South Korea from '82-'85. I'm sure that modern units are much more efficient than the one I had, that utilized a "pilot light" for burner ignition. These units are "efficient" because they only heat the water when you need it.... or ON DEMAND. There is NO STORAGE TANK, nor is one needed. The unit I had installed under my kitchen sink was only about 18"Hx14"Wx12"D, yet it supplied sufficient hot water to fill a large bathtub or take a 5-10 minute shower. My bathroom was located on the other side of the kitchen sink wall. I could use the hot water from my kitchen hot water faucet to make instant coffee in the cup after only 15-30 seconds of operation.
You DON'T RUN OUT OF HOT WATER unless you have MANY MULITIPLE USERS AT THE SAME TIME and exceed the "flow rating" of the unit. Even then, the water will be slightly "hot", but not like it normally is.

Here is basically how an "On-Demand" Hot Water Heater works:

Picture all of this inside a rectangular shaped box similar to the above dimensions. In the bottom you have 2-3 rows of burners similar to a central heating system unit. Above these burners are several coils of copper tubing (picture a small radiator similar to the heater core in your car). This may be one or two levels high, depending on the "flow rating" of the unit. The unit is OFF until you turn on a hot water faucet or tap. As water begins to flow thru the hot water line a "flow meter" inside the unit senses this DEMAND for hot water and actuates a relay which turns on the gas flow thru the burners while simutaneously activating the ignition device for the burners (this is usually a piezo-electric device in modern units). The flames from the burner heat the water passing thru the coils above the burners quite quickly. By the time the water reaches the faucet or tap it is getting "hot" to the touch. This heating oF the water will only continue as long as there is a DEMAND for it, or there is suffieient water thru the "flow meter" to trigger gas flow. There is a thermal protection built into the unit to prevent OVERHEATING under "low flow rate" conditions. As long as you don't open EVERY hot water tap in the house at the same time, most of these units will provide HOT WATER indefinately. When you turn off the hot water faucet/tap, water flow stops and the unit SHUTS OFF the gas flow to the burners IMMEDIATELY.

If you want one with MAXIMUM EFFICIENCY, I'd suggest using a gas/propane system with a "pilotless" ignition system. The higher "flow rate" the system has usually means it has either larger burners, more heating coils above the burners, or both. Most mfgs have a chart to determine your family's needs. With an electric unit it would take at least a minute for the element to get hot enough to heat any water.... similar to the time it takes an electric range element to start cooking with.

Again, a smaller unit could be installed near the kitchen and another near the bathrooms to avoid heat loss thru travel from a central location to all areas of the house the way a common heater storage tank system functions. Although this may cost more initially, it would be the MOST EFFICIENT way to do it in the long run.... and eventually pay for the extra unit by cutting down the operating time of one central unit to get hot water to a remote area of the house.


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## Parker Phoenix (Aug 27, 2006)

We have had one for three years. I can shower, wash clothes, and run the dishwasher at the same time, and have all the hot water I need. Not to mention a $300 tax credit. Buy a Ranai.


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## stev (Aug 27, 2006)

I have tankless in my homes.They are the bomb.And the tax credit is awsome.I wouldnt go bact to a water tank.Ive got 4 bedrooms and 3 baths and it works fine.Never gets cold while flushing and doinglaundry at the same time.There are diferent sizes for bigger homes.www.noritz.com.


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## bustindeer (Aug 27, 2006)

thank you all for the info i do not have gas or propane i switched everything to electric when the gas prices went haywire  so i plan on getting and electric one or two after the info was read  once again thank you all for the advice and info


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## Derek (Aug 29, 2006)

do they make a electric tankless hot water heater????


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## Bruz (Aug 29, 2006)

stev said:
			
		

> I have tankless in my homes.They are the bomb.And the tax credit is awsome.I wouldnt go bact to a water tank.Ive got 4 bedrooms and 3 baths and it works fine.Never gets cold while flushing and doinglaundry at the same time.There are diferent sizes for bigger homes.www.noritz.com.



Stev,

I have 5 BR 4.5 Baths and 2 full kitchens....Which model do you have and how many people at home? 

I would like to look into this but both dealers in my area aren't answering their phones.

Thanks,


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## stev (Aug 29, 2006)

Bruz said:
			
		

> Stev,
> 
> I have 5 BR 4.5 Baths and 2 full kitchens....Which model do you have and how many people at home?
> 
> ...


I ve got the n-132m  13 gallon per minute.It has a thermostat thats at my kitchen wall.And the unit is in my basement.I can control the temp from my kitchen.I keep it at 140 degree.It will go up to 180 degree.2 people in the house .It is 5000 sq ft and it does a fine job of never running out of hot water.The gas bill has dropped $200 for one yr.The unit never fires up till you turn the hot faucet on .We run dish washer 2 showers daily with no problems.I have 1 units in each one of my homes.You wont be disappointed.


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## bradpatt03 (Aug 29, 2006)

i would recommend rinnai...pm me if you're interested


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## Bruz (Aug 29, 2006)

stev said:
			
		

> I ve got the n-132m  13 gallon per minute.It has a thermostat thats at my kitchen wall.And the unit is in my basement.I can control the temp from my kitchen.I keep it at 140 degree.It will go up to 180 degree.2 people in the house .It is 5000 sq ft and it does a fine job of never running out of hot water.The gas bill has dropped $200 for one yr.The unit never fires up till you turn the hot faucet on .We run dish washer 2 showers daily with no problems.I have 1 units in each one of my homes.You wont be disappointed.



How does the square footage factor into the hot water?

 My house is a little over 6,000SF with my wife and 3 kids so would I need a larger unit?


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## stev (Aug 29, 2006)

Bruz said:
			
		

> How does the square footage factor into the hot water?
> 
> My house is a little over 6,000SF with my wife and 3 kids so would I need a larger unit?


That i dont know youd have to check on the site for that.I think its the biggest they make.If need be you coul;d put 2 together


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