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Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

Re: Low water pressure

said by onebadmofo:

I'm already thinking tankless.

Even tankless isn't that great. I ended up having to add a 50 gallon tank as storage to the tankless system to handle peak demand.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1

said by Draiman:

said by onebadmofo:

I'm already thinking tankless.

Even tankless isn't that great. I ended up having to add a 50 gallon tank as storage to the tankless system to handle peak demand.

What would you consider peak demand?
cause it's only me and my wife that live here. We have a dish washer that's used once a week. And a Washing machine that's used once a week as well.
--
Photoshop these nuts in your mouth.


Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS

said by onebadmofo:

said by Draiman:

said by onebadmofo:

I'm already thinking tankless.

Even tankless isn't that great. I ended up having to add a 50 gallon tank as storage to the tankless system to handle peak demand.

What would you consider peak demand?
cause it's only me and my wife that live here. We have a dish washer that's used once a week. And a Washing machine that's used once a week as well.

It all depends on the volume of hot water you use. That's affected by how much water the faucets, shower heads, etc. use aka gpm or gallons per minute. A shower head can use anywhere between 1.5 to 5.5 gpm's. If you have 2 showers going with 1.5's you're only using 3 gpm's but if you have 2 showers going with 5.5 gpm heads your using 11 gpm's! Normally a tankless will have a gpm rating. You might pick a lower rated gpm unit since there is only 2 of you but if you sell the house the next owners might have kids so they need to install a water heater as a storage tank to augment the tankless system. It's hard to say without a complete picture.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7

1 recommendation

reply to onebadmofo

You don't happen to have a water tank on your roof, do you?



onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1

said by cdru:

You don't happen to have a water tank on your roof, do you?



--
Photoshop these nuts in your mouth.


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to onebadmofo

So I'm looking at this and it seems like it would work for me. But what do I know.
»www.homedepot.com/webapp/wcs/sto···WidgetID
--
Photoshop these nuts in your mouth.



Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS

said by onebadmofo:

So I'm looking at this and it seems like it would work for me. But what do I know.
»www.homedepot.com/webapp/wcs/sto···WidgetID

Did you look at the specs on that unit? It shows the gpm flow based on the unheated water temp. If your water is 40 degrees for example and you want 110 degree shower that's an increase/rise of 70 degrees so that unit can only sustain 1.59 gpm's at that rate. It means you need a low flow water saver shower head and nothing else can be running to get the proper water temp. That will vary based on the water temp so in the Summer you'll be much better off but in the Winter you'll peak it out easy.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
kudos:9
Reviews:
·G4 Communications
·Fairpoint Commun..
·Hollis Hosting
reply to onebadmofo

said by onebadmofo:

So I'm looking at this and it seems like it would work for me.

You realize 18Kw is 75A at 240 volts and will barely produce enough hot water for one shower if your incoming water is already pretty warm.

By way of comparison tank type water heaters are typically 3800 or 5500 watts.

/tom


shdesigns
Powered By Infinite Improbabilty Drive
Premium
join:2000-12-01
Stone Mountain, GA
Reviews:
·Atlantic Nexus
reply to onebadmofo

said by onebadmofo:

So I'm looking at this and it seems like it would work for me. But what do I know.
»www.homedepot.com/webapp/wcs/sto···WidgetID

If you have the power to feed it:
Amperage (amps) 75 A

Your old water heater was probably wired for 30-40 amps.
--
Scott Henion

Embedded Systems Consultant,
SHDesigns home - DIY Welder

Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online
reply to onebadmofo

Short answer: No it won't work.

It requires a 75 Amp 240 Volt supply, which requires pretty hefty wires, depending on the distance from your electric panel. Not to mention you may not have a big enough drop. And in the winter will only provide 1.6 gal/minute of hot water.



Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

If you really want to go that direction get the biggest unit you can. I mean if you want to spend $400 why not spend the extra $80 and be safe. You can't just return this type of item after a few months when you find out it's too small but on the other hand if it's too big it just doesn't have to work as hard making it last longer.
»www.homedepot.com/h_d1/N-25ecodZ···13h1QGSo
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


Bob4
Account deleted

join:2012-07-22
New Jersey

1 recommendation

112 Amps! He'll need a new electric drop just for this! And it will barely provide enough hot water in the winter.



Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS

said by Bob4:

112 Amps! He'll need a new electric drop just for this! And it will barely provide enough hot water in the winter.

Yea it's crazy but if that's the path he wants to go down it's not much more work to do 112A vs 75A. He'd need at least 200A service for either.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968

Bob4
Account deleted

join:2012-07-22
New Jersey

1 recommendation

And all to NOT save money!



dcurrey
Premium
join:2004-06-29
Reviews:
·Time Warner Cable
·Cincinnati Bell
·ViaTalk
reply to onebadmofo

Maybe he should look into heat pump type water heaters. At least with them he shouldn't have to miss with new electric lines.

Think they qualify for rebates to cut down on the high cost.

»www.geappliances.com/heat-pump-h···-heater/



Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

This is the model I'd suggest to anyone needing electric heat.
»www.lowes.com/pd_386797-83-GEH50···cetInfo=
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


Bob4
Account deleted

join:2012-07-22
New Jersey

Does GE even make water heaters, or are they still re-branded Rheems?


nokiatech

join:2000-10-18
Stuart, FL
reply to Draiman

Christ. My $400 dollar water heater works just fine.



tschmidt
Premium,MVM
join:2000-11-12
Milford, NH
kudos:9
Reviews:
·G4 Communications
·Fairpoint Commun..
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reply to Bob4

said by Bob4:

Does GE even make water heaters, or are they still re-branded Rheems?

I think the GE heat exchanger water heater is their own design. But I assume they stick it on top of some customized off the shelf tank, but I'm guessing. The reviews I've seen have been mixed. They are very expensive compared to traditional electric heater. This has to be amortized over a relatively short time frame. The analysis I've read indicates the control setpoints are optimized for scoring high on the Energy Star test but may not be optimum for real life use.

Back to the OP to help understand the tradeoff of tank vs tanksless water heaters.

Efficiency for electrically heated appliance is 100%, all of the electrical energy is converted to heat. In a traditional electric heater we then need to look at heat loss through the tank. Given high performance foam insulation very little heat is lost during standby. In the summer losses increase temperate near the heater and if the space is air conditioned must be removed by the HVAC system. HVAC operate at greater then 100% efficiency so it costs less then a BTU to remove every BTU lost by the heater.

In the winter the effect is the opposite. Any heat lost by the heater reduces need to add heat by the heating system. Unless the house is heated electrically the cost of a heating BTU is less then the cost of an electric BTU but it does offset heating cost to some extent.

If you go with the GE heat exchanger unit when the heat exchanger is operating it is pulling heat out of the air and transferring it to the water. The efficiency of this transfer is greater then 100% because the system is simply moving heat around not making it. So in the summer it will reduce air conditioning energy cost because it is removing heat from the air and transferring it to the water. Keep in mind that this is offset to some extend because waste heat from the compressor and fan is dumping some heat back into the conditioned space. In the winter heat transferred from the air to water will have to be made up by the heating system. Since those BTUs are probably cheaper then electricity cost is reduced but every BTU transferred to the water needs to be made up by the heating system.

The GE heat exchanger unit may make sense in the south where AC is needed all the time, but I doubt it makes sense anywhere else. There is also the issue of maintenance and repair. I hate to poo-poo green technology but if it breaks who are you going to find with the skills to fix it.

A much simpler approach would be to capture waste heat from the Air Conditioner and use it to warm water in a preheat tank, then plumb that to a conventional water heater and use electricity to top it up as needed.

/Tom


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to Draiman

said by Draiman:

said by onebadmofo:

So I'm looking at this and it seems like it would work for me. But what do I know.
»www.homedepot.com/webapp/wcs/sto···WidgetID

Did you look at the specs on that unit? It shows the gpm flow based on the unheated water temp. If your water is 40 degrees for example and you want 110 degree shower that's an increase/rise of 70 degrees so that unit can only sustain 1.59 gpm's at that rate. It means you need a low flow water saver shower head and nothing else can be running to get the proper water temp. That will vary based on the water temp so in the Summer you'll be much better off but in the Winter you'll peak it out easy.

I did but...based on the replies (which are actually helpful) it's quite obvious I have no clue about what is a good replacement.

It's seems like a lot to figure in. this is all new to me.
--
Photoshop these nuts in your mouth.


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to Draiman

said by Draiman:

If you really want to go that direction get the biggest unit you can. I mean if you want to spend $400 why not spend the extra $80 and be safe. You can't just return this type of item after a few months when you find out it's too small but on the other hand if it's too big it just doesn't have to work as hard making it last longer.
»www.homedepot.com/h_d1/N-25ecodZ···13h1QGSo

I like that thought process.

but so I understand, to run the unit you linked, I'd still need to upgrade the breaker, and the wiring running to it correct?
--
Photoshop these nuts in your mouth.

Bob4
Account deleted

join:2012-07-22
New Jersey
reply to onebadmofo

You said there are two of you? Just get a traditional 40 or 50 gallon electric water heater. Done. 100% efficient.

You (or the plumber) should check the wiring to ensure that the new heating elements don't exceed your wiring's capacity.


garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus
reply to onebadmofo

said by onebadmofo:

said by Draiman:

If you really want to go that direction get the biggest unit you can. I mean if you want to spend $400 why not spend the extra $80 and be safe. You can't just return this type of item after a few months when you find out it's too small but on the other hand if it's too big it just doesn't have to work as hard making it last longer.
»www.homedepot.com/h_d1/N-25ecodZ···13h1QGSo

I like that thought process.

but so I understand, to run the unit you linked, I'd still need to upgrade the breaker, and the wiring running to it correct?

Sure, of course; plus the incoming drop from the pole, possibly the electric meter pan and complete panel. Likely add another $1500 to the installation.

Get a regular 50 gallon tank and be done with it.


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to Draiman

said by Draiman:

This is the model I'd suggest to anyone needing electric heat.
»www.lowes.com/pd_386797-83-GEH50···cetInfo=

If money was no object...I'd go for it. But unfortunately my pockets are full of lint and my wallet is always running on empty.
--
Photoshop these nuts in your mouth.


Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

said by onebadmofo:

said by Draiman:

If you really want to go that direction get the biggest unit you can. I mean if you want to spend $400 why not spend the extra $80 and be safe. You can't just return this type of item after a few months when you find out it's too small but on the other hand if it's too big it just doesn't have to work as hard making it last longer.
»www.homedepot.com/h_d1/N-25ecodZ···13h1QGSo

I like that thought process.

but so I understand, to run the unit you linked, I'd still need to upgrade the breaker, and the wiring running to it correct?

You'd need to do that with any whole house electric tankless system. Not many people have that type of extra service coming into their house unused.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

said by onebadmofo:

said by Draiman:

This is the model I'd suggest to anyone needing electric heat.
»www.lowes.com/pd_386797-83-GEH50···cetInfo=

If money was no object...I'd go for it. But unfortunately my pockets are full of lint and my wallet is always running on empty.

It shows you could get $600 off that water heater in rebates so $600 vs. $400-480.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to garys_2k

said by garys_2k:

said by onebadmofo:

said by Draiman:

If you really want to go that direction get the biggest unit you can. I mean if you want to spend $400 why not spend the extra $80 and be safe. You can't just return this type of item after a few months when you find out it's too small but on the other hand if it's too big it just doesn't have to work as hard making it last longer.
»www.homedepot.com/h_d1/N-25ecodZ···13h1QGSo

I like that thought process.

but so I understand, to run the unit you linked, I'd still need to upgrade the breaker, and the wiring running to it correct?

Sure, of course; plus the incoming drop from the pole, possibly the electric meter pan and complete panel. Likely add another $1500 to the installation.

Get a regular 50 gallon tank and be done with it.

Huh?? Not sure what you mean about a panel. But if it would end up with that type of cost, shit...forget it.

Ooor re-reading that, maybe I didn't word that properly. I already have a breaker box. What I meant was, that I'd have to get new breakers and heavier wire coming from the break box to accommodate the higher demand from the new W/H.
--
Photoshop these nuts in your mouth.


onebadmofo
gat gnitsoP
Premium
join:2002-03-30
Reading, PA
kudos:1
reply to Draiman

said by Draiman:

said by onebadmofo:

said by Draiman:

This is the model I'd suggest to anyone needing electric heat.
»www.lowes.com/pd_386797-83-GEH50···cetInfo=

If money was no object...I'd go for it. But unfortunately my pockets are full of lint and my wallet is always running on empty.

It shows you could get $600 off that water heater in rebates so $600 vs. $400-480.

Good point.
--
Photoshop these nuts in your mouth.


Draiman
Let me see those devil horns in the sky

join:2012-06-01
Kill Devil Hills, NC
Reviews:
·Verizon FiOS
reply to onebadmofo

Do you know if you have 100a or 200a service? A typical house uses 60-80a so unless you have a 200a panel already you'd be looking at $1,500 to upgrade no matter if you went with a 75a or 112a system.
--
What we're saying today is that you're either part of the solution or you're part of the problem. - E. Cleaver 1968


garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus
reply to onebadmofo

said by onebadmofo:

Huh?? Not sure what you mean about a panel. But if it would end up with that type of cost, shit...forget it.

Ooor re-reading that, maybe I didn't word that properly. I already have a breaker box. What I meant was, that I'd have to get new breakers and heavier wire coming from the break box to accommodate the higher demand from the new W/H.

More likely an entirely new breaker box (panel) sized to your now-required 200A service. Putting a 100+ amp load onto your service is going to mean a lot of "upstream" stuff will likely need upgrading, too. Depending on who is responsible for the line from the pole to the meter you may be on the hook for that, as well as the "pan" (box) the electric meter mounts to, and the line from the meter to your breaker box. Usually the power company will swap your meter for free if you need one with more capacity.

This will cost you thousands of dollars, it's NOT worth it unless it either will give you some payback (this won't) or is needed because you're building on a big addtion to your house.

Your REALLY ought to just put in a new, regular, water heater. The installer should make sure your current breaker and the line to the heater is large enough, but that's usually easy to fix.