Hot water heater

[omc cobra guy]

Its time for a new hot water heater Im thinking about a on-demand water heater has anyone done it? Hows it working out?

 

[roscoe]

I don’t have on demand, I have tankless.
So far so good, but only had it for 18 months.

 

[bajaman123]

water heater

 

[omc cobra guy]

I don’t have on demand, I have tankless.
So far so good, but only had it for 18 months.

Their not the same?

 

[omc cobra guy]

water heater

?

 

[roscoe]

On demand heats the water at the point of use .
So a heater, usually electric for convenience sake, in every room with a faucet.

Tankless, simply replaces your current water heater with a super fast ( high btu ) heater.
Mine is gas, 174,000 btu. Btu size has to be high enough for the number of faucets being used at one time, AND …. For the desired temperature rise needed. I’m in the north, so water enters my basement at 45*F, year round. It pumps out 135* water all day, but I have it set at 123*.

The water still has to flow from the heater through the pipes to the faucets , so you still have to wait for the hot water to get there.

It works for us, it will keep up when we are using 2 showers, and the dishwasher.

Another option I did not go with, is to add recirculating pumps, and return pipes. That would give us instant hot water. But then you are running the pumps and continuously heating the water in the pipes.

 

[jlh3rd]

read up on installation costs and requirements.

 

[flashback]

Likely the existing 240v circuit, if existing heater is electric, will not be sufficient.

 

[KD4UPL]

Are you asking about electric or gas? If gas it's probably a good idea unless your water has a lot of mineral content. If electric you will likely need at least a 400 amp service to your house and still might need a transformer upgrade from the power company.

 

[redneck joe]

water heater

In a tank version, once it is hot it becomes a hot water heater keeping the hot water hot.

 

[Scott Danforth]

Electric tankless water heaters have 3+ high current elements in a manifold, hence the need for a much larger electrical service

 

[redneck joe]

So a base question would be why do you think you want one?

 

[DeepCMark58A]

How long did the old water heater last? Why not replace it with the same?

 

[roscoe]

Went from electric to gas to cut electric bill by $70 a month.
Needed high capacity for the wife's new garden soaker tub, which will empty any conventional water heater.
And needed a power vent heater and an 80 gallon PV runs about $2500 and you are always heating that tankful of water.
The tankless unit was half that at $1200, the same price as a PV 50 gallon tank heater.

 

[Renken2000Classic]

In a tank version, once it is hot it becomes a hot water heater keeping the hot water hot.

That's a good one

 

[nola mike]

I looked into replacing my gas tank with tankless a few years ago. Not an easy conversion, many of the specialized adapters, Etc we're super expensive, in addition to the cost of the heater itself. To say nothing of the increased labor to get it in there. I calculated the payback at something like 15 to 20 years, so not worth it for me in the end. Electric and Gas are apples to oranges because of the different chimney needs the gas unit. The current chimney may not be able to handle the increased heat output of a tankless system.

 

[roscoe]

I looked into replacing my gas tank with tankless a few years ago. Not an easy conversion, many of the specialized adapters, Etc we're super expensive, in addition to the cost of the heater itself. To say nothing of the increased labor to get it in there. I calculated the payback at something like 15 to 20 years,??? so not worth it for me in the end. Electric and Gas are apples to oranges because of the different chimney needs the gas unit. The current chimney may not be able to handle the increased heat output of a tankless system.

I had a completely different experience.
Specialized adapters ?
Just tapped into cold supply, and connected to hot out, and a 120v outlet.
Power vent unit exits out the wall.
Increased labor ?

Parts and labor, $2131.47.

At $800 a year savings over the previous electric heater, cost fully recouped in less than 3 years. So by August of next year, its paid for.

 

[redneck joe]

Not sure of your math so not challenging it per se but we have a long house and use a recirc pump. How does math work into that?