grounding a circuit

electrical question
i recently installed a tankless water heater. it works okay but not great - i think installing two in series would be the way to go - however here is the problem
i have easy access to the grounding rod, but the back of the main panel behind a wall
the original heater is wired up with 6/3 wire - which as i learned actually has four wires in it
could i wire two heaters up with the four wires in the 6/3 and then run new grounds for each heater that go directly to the grounding rod but never make it into the main panel
thanks
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Each heater should be wired to it's own dedicated circuit. Each dedicated circuit should consist of current carrying conductors and a ground wire, run with the circuit conductors. Unless there is something in the manufacturer's instructions requiring a ground rod, you wouldn't use one.

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On Dec 4, 2:01�am, snipped-for-privacy@gmail.com wrote:

i gather this is a tankless electric? how many amps does the existing unit draw? now double that.
how many amps is your total service?
most likely you dont have the amp capacity for two tankless.
did you go tankless to save energy? or get unlimited hot water?
if you have the amp capacity you might put the tankless first, in series feeding a standard electric tank.
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On Dec 4, 2:01 am, snipped-for-privacy@gmail.com wrote:

re: it works okay but not great
Please define "okay" vs "great". In other words, what problem are you trying to solve by putting 2 units in series? Hotter water, longer lasting hot water, something else?
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tankless have issues, in summer there might be hot enough water, but come winter and colder input water temperature output temperature may be forever too low. most people raise the shower temperature at the very end, a tankless owner may never get that warm enough feeling.
another issue is of someone else say runs any other hot water overall water flow increases and showering person is too cold.
lets see what the OPs troubles are
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Yep...I'm aware of the published issues regarding tankless units. That's why I asked the OP to define his problem. I realize he only asked about how to wire them up in series, and didn't ask if 2 in series would make things "great", but I'm certainly curious as to why he feels he needs 2. It's that annoying "inquiring minds" thing again. ;-)
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oh i am curious too. people get such great expectations on tankless, then find out they wasted their money.
using a tankless as a pre heater to feed a standard tank adds nothing to operating costs and provides nearly endless hot water...
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Now you've confused me!
Let's make 3 assumptions:
1 - It's mid-February and my tankless can't provide the temperature I want. 2 - The in-line tank is set to provide hot water at the temp I prefer. 3 - The wife and I are planning to spend enough time in our multi-head full-body shower unit to use up all the hot water in our tank, and then some.
Once we start using the water in the tank, the temp is going to go down and the tank burner is going to come on. Yes, this will take longer than if the water wasn't preheated, but if the stat is set hotter than the incoming water, it will eventually come on. Since there is also flow through the tankless, its burners are also on. Won't this increase my operating costs?
Once we have depleted the tank of all it's water, and it has been completely replaced with the water from the tankless, the temperature is going to be the same as if we only had the tankless, which wasn't hot enough. Where's my "nearless endless" hot water coming from?
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DerbyDad03 wrote:

I agree. I would put the tank first, set at a low temperature. That way the tank would run very efficiently, since the heat losses to ambient would be minimal. Since the tankless now does not have to provide as large a temperature rise, it should be capable of providing you the hot water you need.
Of course, they would have to be on separate circuits.
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its a interesting area..........
first your trouble is really excess use of water.
but putting the tank heater first set on low gains you little.
so you have a tankless feeding a standard tank then feeding your shower.
shower calls for water, tank provides water, incoming water to tank is preheated most of the way to the temp you want.
your regular tank assuming its reasonable size burner will run constantly, but hot water supply should be endless.
the energy to heat the water is the same with or without a tank, except the tank adds some standby losses. in the winter they help heat your home.
consider this.
assume you want 130 degree shower temperature
now for some reason the incoming water temperature is 100 degrees. rather than 50 degrees in the winter.
wouldnt a standard tank have a easier time keeping up if the input water is already very warm?
with a tankless feeding a standard tank the pre heated water entering the regular tank would mean never ending hot water since the burner on the regular tank coulds keep up.
plus the overall fuel used is the same. less some minor standby losses
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re: first your trouble is really excess use of water
I'll accept being accused of "excess use of water" any time the wife wants to stay in the shower with me long enough to empty the water heater. That's not even worth discussing.
re: the overall fuel used is the same
I'll grant you the energy use assumption since it would really hurt my brain to figure out if you are right or wrong on that point. :-)
However, I have my doubts about ths point, but can't really present anything more than "I can't know unless I try it."
"with a tankless feeding a standard tank the pre heated water entering the regular tank would mean never ending hot water since the burner on the regular tank could keep up"
I guess I'd need to see (or do!) the math before I could agree that the burner on the tank could maintain a 130 degree output with a 100 degree input and constant draw off. That would obviously depend on the tank size, BTU of burner and the flow rate. You may very well right.
For now, I'll simply stick with my 50 gallon standard tank, my one- headed shower, and thank the Lord for the times my wife helps me use up all the hot water.
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thanks for all of the input
the tankless discussion could go on for hours - what i really have is an electrical question - does a circuit need to be grounding inside of the main box - or can it be grounded to the grounding rod - which is not inside the box.
in terms of setting up a tank/tankless system - i am sure it would work - however one of the issues with wanting a tankless heater is space - so having both heaters is less than ideal
the current heater draws 55 amps - the service is 200 amps - i think i could add another heater and still be okay
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snipped-for-privacy@gmail.com wrote:

How about a recirculating pump on the shower drain?
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On Mon, 3 Dec 2007 23:01:12 -0800 (PST), snipped-for-privacy@gmail.com wrote:

... but only 3 insulated wires, that is the problem. You can't use a bare wire for a circuit conductor.
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On Dec 4, 11:37�am, snipped-for-privacy@aol.com wrote:

in any case 6 gauge wire is likely too small to run 2 tankless on. the more important question is the main panel capable of supporting 2 tankless plus all other home loads
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