Water heater wiring for generator hookup and to 120 VAC power?

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Plus, does it pay off to work so hard to make an exhaust piping system for something that may not be likely to live long.
I changed my exhaust to a 3/4" copper ell and tubing 8" in length. Slotted the end of the ell and used a SS hose clamp it to the steel exhaust. Just friction tween the ell and the tube.
The other end goes through a 3/4" hole in a little 1/8" thick rectangle of sheet of asbestos board (from a kiln) attached to a 6" high x 36" wide sheet of plywood that seals the single hung window.
I ran it for 30 minutes today and I could not detect any leaks or shifting.
Not a lot of work.
BTW The generator ran for 30 minutes and nobody in my house even noticed it running.
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On 30 Nov 2005 16:29:06 -0800, snipped-for-privacy@aaronj.com wrote:

You must be the new code book poster child? ;-)
I don't know where to start.
It's not about your ability. It's about _liability_.
You must just be trolling.
-zero
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Nonono. Never use a generator outdoors. That wastes about 80% of the fuel's heating value. You might run the exhaust from a $900 1500 W Honda generator with a $2K grid-tie inverter into the top of a $200 gas water heater that preheats water for the usual water heater, then outdoors, all inside a small plastic film room in the basement, depressurized by the combustion airflow, with a CO detector outside the room.
Nick
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Actually a small exhaust-to-water heat exhanger would provide quite a bit of hot water.
I considered it but I am concerned about the steam flash problem and the other complexities involved.
My system is up and running fine in my garage. We can't hear it running in the house nor can our neighbors.
Here's how I connected the 220 VAC generator cable to the W/H.
220 to 220.
Open one wire of the W/H to the center of a SPDT swtich. One throw to A/C from panel, the other to a SPST switch.
The other end of the SPST switch to Neutral.
(The prongs of the generator plug are of course energized and an plastic insulator cover was fabricated for safety - no touch.)
With grid power, everything normal.
No power, flip off Main Breaker, throw the SPDT switch away from panel to lessen the load on my 3,000 watt generator.
I also flip off all other 220 breakers. Generator is used only for 120 devices and the small breakers.
Plug in cable, start generator. Generator feeds house through W/H breaker.
Hot water needed? Throw the SPST switch to neutral and the H/W heater is using 1/4 the power (~850 Watts) on 120 VAC than it uses at 220.
Simple, efficient, and for me, quite safe.
For photos, email me.
YMMV
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I've been tempted to do that. I just leave it in my garage with a front and rear door open a foot. Yes, I know how dangerous it is, but it doesn't seem to bother the CO detector.

Is your generator ground connected to the frame? If so, you don't want to ground the frame again. And if it isn't there is no particular reason to gound the frame.

Well, it appears (as well as I could understand it) to be okay, aside from being illegal and dangerous, but why do something so complicated? What are you trying to accomplish?
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Toller,
Thanks for your thoughtful reply.
I meant CO detector, but couldn't be give thethe benfit of the doubt.
If you lived therough Francism Jeanne, and wilma, you would understand what we are attempting to accomplish in SE FL.
I want the quickest, , quietest, cheapest, longest running, genrator hookup for standy for minimum power and which requires minimum effort to get running.
First the generator garage issue: My welds are strong enough to trust my life on when I ride my recumbent trikes and other vehicles that I have built over the years. Also, my $100 elevator in daily use for over 3 years was also condemned by the usual Google lurkers who never seem to trust their own abilities to build anything that their life would depend upon. What happened to the pioneer spirit? "Leave it to the professionals" is their motto. True in many cases but not in all cases. Why have a Forum on Home repair? Just use the Yellow pages and hire a pro.
There are 2 closed interior doors separating the garage from the house. The Garage door will be partially open for ventillation and for oxygen for the generator.
The genertator is a 3000-3500 watt 6.5 hp model. Modest output, enough for a refridge and a few lights etc.
Complication is not the case. Just the opposite. A short 3 wire cable from the generator to a junction box and 2 switches.
Throw one switch for generator power to the entire house.
Throw the other switch for 120 VAC hot water.
What could be simpler with fewer wires or switches?
The 4th crooked lead in the generator receptacle does not measure 'short' to the generator case not to any other terminal.
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I'd feel better about it if you have a flexible section near the generator. If your construction is entirely rigid then forget it, it will eventually break no matter how good your welds are unless it's *extremely* short. Is it a threaded connection into the engine? That's a good place for a break if the vibrating engine is rigidly connected to a lengthy pipe. That condo emergency genset you mention...if it was indoors it surely had some sort of flexible pipe connection. Does your engine vent the crankcase back to the intake? Finally, a decent ventilation fan either bringing in fresh air or exhausting inside air, with either a vent or window that will be open during generator runs to allow for circulation is a bare minimum. Then maybe.
Is this gasoline or NG? Where is the tank vented? What about spills on refueling? So much simpler and safer just to take the thing outside. Then you can tell everyone about how you will hook it up via the A/C disconnect box.
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Hey, tell us more. I've always thought stairs were a waste of money and floorspace, compared to a DC winch or a trapeze or a bosun's chair with a counterweight.
Nick
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The same switch that connects generator to water heater must also disconnect AC mains from water heater. Switch must be 'break before make' type. It does not matter how many times you say "it is off". Humans have a bad tendency to always make the exception occur. A design must be human proof.
Design must be 'not mechanically possible' to ever connect generator until heater has been disconnected from AC mains. Switching equipment is simple to obtain which is just another reason why the heater must always disconnect from AC mains before generator makes a connection. Any residential procedure that calls for human knowledge is unnecessarily and unacceptfully dangerous.
If anyone ever makes a mistake (connects AC mains and generator together), then 100% blame belongs on the human who built that mistake. If anyone can make a mistake, that human who installed the dangerous system should be hung by his balls - this last sentence only my opinion. All other sentences are required by both code and common sense.
snipped-for-privacy@aaronj.com wrote:

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Meanwhile, where is the all so necessary safety ground. Earth ground rod is not a safety ground.
w_tom wrote:

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Safety Ground at the panel box wired to Neutral.
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Where does generator connect to safety ground? For example, assume the generator has a circuit breaker. Assume one side of 240 volts shorts inside heater. Now heater frame is electrically hot. Where is the conductive circuit that goes out of generator, through short to water heater frame, then (and this is the missing part) back to generator on either safety ground or other side of 240? Without that direct circuit, then circuit breaker / fuse may not trip/blow. Demonstrated is why all building safety grounds (ie one in breaker box) must connect to safety ground on generator by a dedicated safety ground wire of sufficient gauge.
snipped-for-privacy@aaronj.com wrote:

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