Electric Tankless Water Heaters

[narzy]

Our water heater took a crap, showers are cold and the boys are raisins. We need to replace it and got a quote for 4g's to get a NG one installed. The old one has a 200+v circuit to it already so the wiring for a electric tankless has already been done. Our Avg. Ground temp is 50* at the coldest if that helps. It also needs to get the water hot enough to do dishes and laundry.

I'm looking at the Tempra 36 from Stiebel Eltron but I don't know anything about these things or what a good brand might be.

 

[Nitemare]

Unless there is 1-2 tops in the household I'd avoid a tankless hot water heater

 

[BigJ]

Originally posted by: Nitemare
Unless there is 1-2 tops in the household I'd avoid a tankless hot water heater

Size your unit properly and it won't be a problem for most areas of the country.

 

[KK]

you sure the electric run to the area has enough capacity amp wise?

 

[BigJ]

Originally posted by: KK
you sure the electric run to the area has enough capacity amp wise?

Judging by this:

http://www.stiebel-eltron-usa.com/techdata_tempra.html

Not a chance in hell.

 

[KK]

Originally posted by: BigJ

Originally posted by: KK
you sure the electric run to the area has enough capacity amp wise?

Judging by this:

http://www.stiebel-eltron-usa.com/techdata_tempra.html

Not a chance in hell.

yeah, he'll probably need to up his main breaker box too to handle it. $$$

 

[BigJ]

Originally posted by: KK

Originally posted by: BigJ

Originally posted by: KK
you sure the electric run to the area has enough capacity amp wise?

Judging by this:

http://www.stiebel-eltron-usa.com/techdata_tempra.html

Not a chance in hell.

yeah, he'll probably need to up his main breaker box too to handle it. $$$

He really should decide to go over to a non-electric (gas) tankless. Electric tankless heaters are only going to be good if you need relatively little hot water at a single time. Anything else and you want gas.

OP, go here to do some rough calculations:

http://www.chilipepperapp.com/tankless.htm

Then you can look for models based on the numbers you get from there.

Upgrading to a 300A Service is going to be MAJOR money. You're looking at around $2,000 just for that service upgrade.

 

[JC86]

I dunno the amps or circuit requirements but I have a Rinnai tankless heater and it gets the job done. I can do a load of laundry and take a shower at the same time and feel no lack of hot water or water pressure. However, the further away the faucet is from the water heater, the longer it takes for hot water to start flowing. My bathroom is right above the heater and I get hot water within seconds of turning on the faucet but the kitchen sink takes a couple of minutes for hot water to start flowing. Might want to keep that in mind.

 

[BigJ]

Originally posted by: JC86
I dunno the amps or circuit requirements but I have a Rinnai tankless heater and it gets the job done. I can do a load of laundry and take a shower at the same time and feel no lack of hot water or water pressure. However, the further away the faucet is from the water heater, the longer it takes for hot water to start flowing. My bathroom is right above the heater and I get hot water within seconds of turning on the faucet but the kitchen sink takes a couple of minutes for hot water to start flowing. Might want to keep that in mind.

Your Rinnai is a gas heater, correct?

 

[Rubycon]

Tempra? 36 requires a 300A minimum electrical service

LOL @36kW on 1? power. That will make the lights dim in the neighborhood with everyone that shares the same distro transformer.

Like the old Magic Chef microwave ovens (days of the "radarrange") - the controller pulsed the magnetron on and off quite rapidly and this made the lights get dim and bright rapidly at an annoying pace. Laser printer fuser heater duty cycles are similar.

I could not imagine a 36kW load getting switched on and off on a single phase res line though. :laugh:

 

[dawp]

Originally posted by: JC86
I dunno the amps or circuit requirements but I have a Rinnai tankless heater and it gets the job done. I can do a load of laundry and take a shower at the same time and feel no lack of hot water or water pressure. However, the further away the faucet is from the water heater, the longer it takes for hot water to start flowing. My bathroom is right above the heater and I get hot water within seconds of turning on the faucet but the kitchen sink takes a couple of minutes for hot water to start flowing. Might want to keep that in mind.

that happens with any water heater, not just tankless, you don't heat the pipes or it would be redundant to have a water heater in the first place. even insulated pipes will eventually cool.

 

[xgsound]

Was your old one a tankless or not? If it was not the cost to prepare for tankless (gas or electric) is higher than the units themselves. They both draw unusually high power (volume of gas or amps of electric) to produce instant hot water for a whole house and require special provisions in the form of amps or 3/4 inch gas line with expensive (and hot) venting.

If you already have a tankless, replace with a similiar (electric or gas) type so you don't have to pay for new gas line, venting, or high amp (80A to 180A) lines when you already have the expensive stuff for the other kind. The most expensive electric tankless at Lowes is $599 and uses 120A of 220V. The one you linked to uses 180A of 220V.

A 50 gal tank model in gas or electric (tank only - no install) will be between $250 to $400 plus install from any Lowes or Home Depot. The gas only needs a 3/8 gas line and normal venting. The electric only needs 1 30A 220V line. You probably already have one of these. If you have more than 2 baths a bigger tank (or time schedule for showers) will be in order.

All this is meaningless if the $4,000 doesn't bother you.


Jim

 

[sao123]

Originally posted by: narzy
Our water heater took a crap, showers are cold and the boys are raisins. We need to replace it and got a quote for 4g's to get a NG one installed. The old one has a 200+v circuit to it already so the wiring for a electric tankless has already been done. Our Avg. Ground temp is 50* at the coldest if that helps. It also needs to get the water hot enough to do dishes and laundry.

I'm looking at the Tempra 36 from Stiebel Eltron but I don't know anything about these things or what a good brand might be.

as others have said... avoid ELECTRIC tankless water heaters... if you can, get a natural gas or LP one. Going to an electric tankless will probably require you to rewire your entire service entrance... (3-4K)...If you only have electric, then go back to your standard electric water heater.

 

[Linflas]

So from the comments in this thread if you have an existing gas water heater and it goes bad the tankless systems work well enough now to merit consideration? There are only 2 of us that would be using it and our current water heater is getting to the age where it could go bad so it would be nice to switch to one of these when that happens.

 

[Pepsei]

like other said, isn't gas tankless water heater better? endless supply of hot water ftw.

it is %*^$ing expensive thou. i considered going to taiwan to pick one up from there, it's also expensive there but 1/2 price. it'll probably fit in one of the luggage. but i'll have to research more and pick up a right model that works here.

 

[Scarpozzi]

Originally posted by: Linflas
So from the comments in this thread if you have an existing gas water heater and it goes bad the tankless systems work well enough now to merit consideration? There are only 2 of us that would be using it and our current water heater is getting to the age where it could go bad so it would be nice to switch to one of these when that happens.

I'm going to say it depends on where you live. If you're in the North and the tankless system has to heat the water an extra 15 degrees (20-30%), you're going to need a bigger system. Bigger systems cost more to operate and buy. Tankless operational costs are generally lower, but when you get to the bigger systems the breakeven point is lower because you may not have needed to use such high amperage on the traditional system.

Longevity of tankless systems is also a concern. Most people can get 12-18 years out of a hot water heater. If an element goes out, you're talking about $10 or less to replace most of them. Tankless systems aren't a standard, so you may be stuck dealing with whatever the vendor wants to charge you. You may save $50 a year in electricity, but it may take you 8-10 years to breakeven if you had bought the traditional water heater...

You just need to do the research and run the numbers. (or get the tankless simply because it's cool....that's what I wanna do)

 

[slsmnaz]

Originally posted by: Scarpozzi
You just need to do the research and run the numbers. (or get the tankless simply because it's cool....that's what I wanna do)

that's 1 reason but another is for space. I don't have a huge house and removing the heater allowed me to create a laundry room and expand my kitchen a bit.

 

[Pepsei]

oh another reason i want to get it is that my pilot light keeps going out once or twice a month.... i guess it had something to do with the heater in the garage? when i relight the pilot light, i have to wait for about 30minutes or more for the full tank of water to reheat. a tankless would not have that problem.

 

[Dirigible]

Originally posted by: slsmnaz

Originally posted by: Scarpozzi
You just need to do the research and run the numbers. (or get the tankless simply because it's cool....that's what I wanna do)

that's 1 reason but another is for space. I don't have a huge house and removing the heater allowed me to create a laundry room and expand my kitchen a bit.

That's why I'd get one. I have a small and old house (one closet in the entire place does not make my wife happy) and if I replaced the water heater with tankless it'd clear up some room.

 

[TastesLikeChicken]

When my wife and I remodeled the kitchen we put in a Steibel Tempra 24. It provides hot water for the kitchen sink, dishwasher, and washing machine in the garage. We decided to put one in because the normal water heater is on the opposite end of the house and it would take 2+ minutes for the water to get hot in the kitchen.

It cost about $400 for the electriician to come in and run the 100A line and hookup the tankless unit. We were already having the entire kitchen replumbed anyway so it didn't impact much in the way of plumbing costs.

I love the unit. Having virtually instant hot water in the kitchen is great and I don't have to waste a couple gallons of water anymore waiting for it to warm up. We've had the unit for a couple of years now and it hasn't had a single problem.

 

[Adul]

Originally posted by: Linflas
So from the comments in this thread if you have an existing gas water heater and it goes bad the tankless systems work well enough now to merit consideration? There are only 2 of us that would be using it and our current water heater is getting to the age where it could go bad so it would be nice to switch to one of these when that happens.

Tankless gas water heater is the way to go. You don't waste gas heating water that isn't used. Well worth it.

 

[sao123]

Originally posted by: Scarpozzi

Originally posted by: Linflas
So from the comments in this thread if you have an existing gas water heater and it goes bad the tankless systems work well enough now to merit consideration? There are only 2 of us that would be using it and our current water heater is getting to the age where it could go bad so it would be nice to switch to one of these when that happens.

I'm going to say it depends on where you live. If you're in the North and the tankless system has to heat the water an extra 15 degrees (20-30%), you're going to need a bigger system. Bigger systems cost more to operate and buy. Tankless operational costs are generally lower, but when you get to the bigger systems the breakeven point is lower because you may not have needed to use such high amperage on the traditional system.

Longevity of tankless systems is also a concern. Most people can get 12-18 years out of a hot water heater. If an element goes out, you're talking about $10 or less to replace most of them. Tankless systems aren't a standard, so you may be stuck dealing with whatever the vendor wants to charge you. You may save $50 a year in electricity, but it may take you 8-10 years to breakeven if you had bought the traditional water heater...

You just need to do the research and run the numbers. (or get the tankless simply because it's cool....that's what I wanna do)

More amperage on a gas water heater? you dont say...


We have the Bosch tankless gas water heater... in cold pennsylvania.
Plenty of hot water for 2, plus dishwasher, laundry, etc.

 

[narzy]

Ok so this goes from bad to worse...

They wanted 4k to do the tankless gas, whoever designed and built the house was a complete moron...the gas company also loses points for their contributions. The Gas meter is in the wrong place. This would have caused us to have to run a one inch gas line around the back of our house to feed the tankless. Unit price is 2.5k install was an additional 1.5k...no way in hell. So we go and pick up a 50gal electric, basically replaces what was there before. Get it in place and hooked up and the pressure relief valve doesn't fit. So my step father goes back and gets an extension. During that time I fill the tank and manage to over fill it and water comes flowing out the top, where the pressure valve was suppose to be. At that point I turned off the water and finished wiring the electricity. I dried everything up, put the cover back on and flipped the switch. POP! Blew the breaker instantly. I was sure I had everything wired properly the first time but maybe I got it backwards so I reverse the wiring...Louder pop and this time in the panel...240v gets angry when it is shorted .

At this point I take off the element access panel and discover the insulation is soaked from my over filling the tank. Water + 240v = oops...That wasn't the problem however. It turns out that this unit was a floor model and someone rewired it completely improperly. Like in a bad way...We're taking pictures and going to show the store that sold it to us and have them come out and fix this.

 

[Rubycon]

Why in the world would you fill the tank with an open fitting? That's akin to getting in a lifeboat with an uncapped through hull fitting a few inches above the waterline!

Since the water spilled over the top and soaked the insulation between the tank and the outer shell the supplier may nullify any warranties due to improper installation technique.

 

[sao123]

Originally posted by: narzy
Ok so this goes from bad to worse...

They wanted 4k to do the tankless gas, whoever designed and built the house was a complete moron...the gas company also loses points for their contributions. The Gas meter is in the wrong place. This would have caused us to have to run a one inch gas line around the back of our house to feed the tankless. Unit price is 2.5k install was an additional 1.5k...no way in hell. So we go and pick up a 50gal electric, basically replaces what was there before. Get it in place and hooked up and the pressure relief valve doesn't fit. So my step father goes back and gets an extension. During that time I fill the tank and manage to over fill it and water comes flowing out the top, where the pressure valve was suppose to be. At that point I turned off the water and finished wiring the electricity. I dried everything up, put the cover back on and flipped the switch. POP! Blew the breaker instantly. I was sure I had everything wired properly the first time but maybe I got it backwards so I reverse the wiring...Louder pop and this time in the panel...240v gets angry when it is shorted .

At this point I take off the element access panel and discover the insulation is soaked from my over filling the tank. Water + 240v = oops...That wasn't the problem however. It turns out that this unit was a floor model and someone rewired it completely improperly. Like in a bad way...We're taking pictures and going to show the store that sold it to us and have them come out and fix this.

They??
Man... if you can install an electric... you can install your own gas tankless... I did.

yes I had to run some higher volume gas pipe... buy black iron pipe at lowes, theyll cut and thread it for free.
I bought and self installed my Bosch for around $1k, including new waterlines, new gas pipe, and new 4 inch vent piping.