Garage Generator Install

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firedawgy
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Garage Generator Install

Post by firedawgy » Thu Nov 14, 2019 7:56 am

[Split to new topic -- mod oldcomputerguy]

I know this issue has been beat to death but I would like to get an input on my idea. #1 running this generator outside would be a very tough task, so have been crunching ideas to install it in the garage. I have standard 3br house, attached garage with FROG. I have a 8800w generator I planned on running off natural gas. Planned on building a generator box in the corner of the garage, with a large fan installed on the garage side of the box to push the generated heat thru a vent out the side of the house, now for the kicker, the exhaust. Recently I upgraded my gas hot water heater to a gas tankless which has its own exhaust out the side of the house, so that leaves the old hot water heater exhaust out the ceiling to the roof. Whats your input on running the exhaust to that exhaust stack leading to the roof if I installed a inline fan at the bottom of the stack to push the exhaust up the stack? I would of course double wrap the exhaust to the stack with insulation to keep it safe and cool in the garage and install CO detectors in the house and garage. If this sounds acceptable any suggestion for a muffler. I think I have hit all the major safety points and would love the input from others here. Thanks all

smitcat
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Re: Garage Generator Install

Post by smitcat » Thu Nov 14, 2019 8:45 am

firedawgy wrote:
Thu Nov 14, 2019 7:56 am
[Split to new topic -- mod oldcomputerguy]

I know this issue has been beat to death but I would like to get an input on my idea. #1 running this generator outside would be a very tough task, so have been crunching ideas to install it in the garage. I have standard 3br house, attached garage with FROG. I have a 8800w generator I planned on running off natural gas. Planned on building a generator box in the corner of the garage, with a large fan installed on the garage side of the box to push the generated heat thru a vent out the side of the house, now for the kicker, the exhaust. Recently I upgraded my gas hot water heater to a gas tankless which has its own exhaust out the side of the house, so that leaves the old hot water heater exhaust out the ceiling to the roof. Whats your input on running the exhaust to that exhaust stack leading to the roof if I installed a inline fan at the bottom of the stack to push the exhaust up the stack? I would of course double wrap the exhaust to the stack with insulation to keep it safe and cool in the garage and install CO detectors in the house and garage. If this sounds acceptable any suggestion for a muffler. I think I have hit all the major safety points and would love the input from others here. Thanks all

"I think I have hit all the major safety points and would love the input from others here. Thanks all"
Welcome firedawgy-
- it will not likely meet code in your area , check first
- it will not likely be insurable , check with you home insurance
- I would also check with your local fire department fire there inputs.
On a risk/reward basis this is one of the worst paths to take. Find a way to install it away from the home.

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Re: Garage Generator Install

Post by Jack FFR1846 » Thu Nov 14, 2019 8:52 am

I can't give you concrete reasons, but boy....this doesn't "feel" right to me. I have a generator and the one 3 day power outage we had, I set it up outside our basement walkout, running the line into the door, with a bunch of insulation sealing air out. My fear would be that "something" might go wrong. A raccoon decides to come down the pipe, blocking it.....something falls off, leaving the exhaust to pour into the garage. Generators vibrate a lot. I know I wouldn't sleep with any path for the exhaust to possibly get in.

I guess this is the same kind of fear I'd have for people who use kerosene heaters inside their house, although I get that you're doing what you can to avoid exhaust gasses from being trapped inside.
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samsoes
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Re: Garage Generator Install

Post by samsoes » Thu Nov 14, 2019 8:57 am

firedawgy wrote:
Thu Nov 14, 2019 7:56 am
I have standard 3br house, attached garage with FROG.
What is FROG? (Assuming, of course, it's not an amphibian.)
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a_movable_life
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Re: Garage Generator Install

Post by a_movable_life » Thu Nov 14, 2019 9:00 am

There are several videos on youtube of people using half height garden sheds/storage boxes for their generators away from the house. They poured a slab and bolted it down as well.

If anything it gets the noise further away from the home.

HomeStretch
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Re: Garage Generator Install

Post by HomeStretch » Thu Nov 14, 2019 9:02 am

Your plan to install a generator in a garage attached to your house sounds unsafe. My town requires a permit for generator installs. The unit has to be installed outdoors and xx feet from anything that would allow carbon monoxide into the home like a venting window or AC unit. What you are proposing would not meet code or pass inspection in my town.

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firedawgy
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Re: Garage Generator Install

Post by firedawgy » Thu Nov 14, 2019 9:03 am

FROG, Finished Room Over the Garage

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Blueskies123
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Re: Garage Generator Install

Post by Blueskies123 » Thu Nov 14, 2019 9:04 am

You say it is hard to run the generator outside, why?
This sounds incredibly dangerous. I cannot see how you can prevent exhaust leaks after a while with all the vibration or even leaks from the generator itself. Then you will have gasoline vapor leaks while refueling.
For your family's sake do not follow through with this idea.
Again, I go back to my first question. Why is it such a problem to put the generator outside?

ddurrett896
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Re: Garage Generator Install

Post by ddurrett896 » Thu Nov 14, 2019 9:17 am

Not worth the risk.

Put it in a detached structure, even one of those cheap plastic sheds or just wheel outside and buy a generator cover for it in case it's raining. They cost like $150, cheaper than what you are proposing.

SimonJester
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Re: Garage Generator Install

Post by SimonJester » Thu Nov 14, 2019 9:45 am

I doubt the generator is designed to have its exhaust routed through a flue like that.
There are very specific requirements surrounding exhausting natural gas appliances.

You could cause back drafting of the water heater which can then force its CO into the living space.

Also burning natural gas consumes oxygen, your generator needs a fresh air supply

As others pointed out not upto code and the risk here is lethal.

Found this online regarding installing a genset generator indoors

If you decide to install a genset inside a building here are some technical details that are typical for most designs.
* The radiator side of the genset needs to be ducted to the outside. Typically the radiator duct area needs
to be at least 1.5X the area of the radiator.
* Intake louvers need to be mounted on the wall (usually the wall opposite the radiator duct). The area of the
intake louvers needs to be at least 2X the area of the radiator.
* The genset will usually come with the muffler and pipe package shipped loose. The muffler is usually anchored
to the wall or ceiling in the genset room. The engine is then connected to the muffler using a piece of flexible
pipe. This flex will absorb most of the engine vibration and prevent damage to the muffler mounting.
* The installer will need to purchase a wall thimble. Because the exhaust pipe gets very hot it must be isolated
where it passes through the building wall or ceiling. The thimble performs this function. To purchase a thimble
you will need to spacify the wall thickness and what it is constructed of. Note that propane and natural gas
fueled gensets burn hotter than their diesel counterparts.
* The genset building should NOT be constructed of wood. It should be a masonry building.
* Per the National Electric Code you will need at least 3 feet clearance on all sides of the genset.
* Vibration isolators are used between the genset skid and the floor foundation to reduce sound and vibration
transmission to the building.
"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety." - Benjamin Franklin

iamlucky13
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Re: Garage Generator Install

Post by iamlucky13 » Thu Nov 14, 2019 11:48 am

At the most basic level, this is a fuel burning appliance inside a building. Just like a furnace or wood stove, this has risks, but it should be possible to address those risks, and while I don't know any details, I have seen generators installed indoors in commercial applications.

As an installed appliance, it would likely be subject to code requirements, and there might not be an existing code prescription for this case. It should be possible to qualify such an installation without such a prescription, but I'm not sure what level of qualification is needed. You may have difficulty finding an installer that would know how to design and qualify the safety of such an installation. It is possible that some of the manufacturers may be able to help you get in contact with one, or may have documentation on requirements for an indoor installation.

Some of the considerations the qualified person will likely cover are exhaust height insulation and height, make-up air supply, fire protection (especially if fuel is planned to be stored inside), distance to combustibles and to walls, and cooling air flow.

lazydavid
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Re: Garage Generator Install

Post by lazydavid » Thu Nov 14, 2019 12:20 pm

a_movable_life wrote:
Thu Nov 14, 2019 9:00 am
There are several videos on youtube of people using half height garden sheds/storage boxes for their generators away from the house. They poured a slab and bolted it down as well.

If anything it gets the noise further away from the home.
This is what I did, and it works extremely well. It does mean I have to go outside to start it and connect the extension cord to the power inlet on the side of the house. But on the flipside, there's zero risk of killing my entire family with CO poisoning, and as you point out, it helps a lot with the noise. When my 5hp air compressor runs in the garage, it makes quite a racket. I can't imagine how loud the generator would be in there.

Broken Man 1999
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Re: Garage Generator Install

Post by Broken Man 1999 » Thu Nov 14, 2019 12:44 pm

I wouldn't do it, even if I could do it to code, with insurance, and fire department blessings.

Just because you can do something, doesn't mean you should.

One phobia I developed after being confined to a wheelchair is the fear of fire. Freaks me out. I currently have four fire extinguishers in my home, and one in my van. I have wheelchair ramps in three exits.

Having a generator in an enclosed area, no matter the venting, would just add to my phobia. I have two carbon monoxide detectors for my non-vented gas fireplace logs, which have a detector as well.

But, obviously I'm very biased. A bit, OK, a lot!

Although, I never had a generator in an enclosed area when I was able, so there is that.

Broken Man 1999
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Voltaire2.0
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Re: Garage Generator Install

Post by Voltaire2.0 » Thu Nov 14, 2019 1:29 pm

Running a generator inside the building? What could go wrong beside the noise, the carbon monoxide and the fire risk?

Back-up generators are designed to be located outdoors.

jharkin
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Re: Garage Generator Install

Post by jharkin » Thu Nov 14, 2019 3:37 pm

NO

I repeat NO


None of what you propose is code legal or insurable. The building code absolutely prohibits multiple appliances sharing a flue and I am fairly certain that is by far not the only thing that would be in violation running a gas powered generator indoors.

Please just dont do this. Suck it up like the rest of us and run a cord outside.

Big Dog
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Re: Garage Generator Install

Post by Big Dog » Thu Nov 14, 2019 3:45 pm

Don't forget that CO has been shown to penetrate wallboard. Now, I assume that your garage walls are supposed to be fire-resistant, but still, this is a REALLY bad idea.

https://www.sciencedaily.com/releases/2 ... 124254.htm

Instead, add some solar panels and invest in a Tesla Powerwall.

NewMoneyMustBeSmart
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Re: Garage Generator Install

Post by NewMoneyMustBeSmart » Thu Nov 14, 2019 3:47 pm

firedawgy wrote:
Thu Nov 14, 2019 7:56 am
Whats your input on running the exhaust to that exhaust stack leading to the roof if I installed a inline fan at the bottom of the stack to push the exhaust up the stack?
I wouldn't do it. Doing it wrong would leak carbon monoxide into the garage into the house and kill people.

Broken Man 1999
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Re: Garage Generator Install

Post by Broken Man 1999 » Thu Nov 14, 2019 4:45 pm

Op, what is your primary reason for not having the generator outside?

You can get generators that kick in with loss of commercial power.

Quieter, isolated from living areas, takes up no garage space, enclosed with noise dampening materials, always ready to go.

My generator is staged outside a garage wall, connects to a permanent plug that is hard wired to my transfer panel inside. I had my propane company install an LP gas head right where I can hook up the generator with a quick-connect hose. Plug the output to the receptical in the outside wall, done. Generator is electric start, a sturdy 8000W unit powered by a Honda engine. The unit has wheels, from the time we roll it out, 15 minutes later we can test it, and we are ready for loss of power. Fortunately we get way more than 15 minutes to prepare for the most likely need, a hurricane.

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chipperd
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Re: Garage Generator Install

Post by chipperd » Thu Nov 14, 2019 4:58 pm

Risk/reward in this scenario doesn't work for me. We run our's outside (8500) with 25 foot cord and back feed through the dryer plug (after shutting down the main and all breakers so we don't feed the system and keep our home a closed system). Then just flip on breakers we want/need to run major needs. We run the cord through the window and use a couple towels to insulate the cracked open window. OP idea just "smells" funny to me.

cashboy
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Re: Garage Generator Install

Post by cashboy » Thu Nov 14, 2019 5:17 pm

please, no.

contact your local Code Enforcement, and the Fire Department, for guidance.
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fallingeggs
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Re: Garage Generator Install

Post by fallingeggs » Thu Nov 14, 2019 6:52 pm

I'm going to go the other way and suggest that it is entirely possible to, in theory, safely route the exhaust outside of the house. Motor and sailboats of all sizes do this with their inboard engines and generators. But these are diesel, which isn't combustible, but they still store and use propane on-board. In addition to venting the exhaust, you'll need sensors to turn everything off if a propane leak is detected; again, something every boat has.

I just wouldn't try to do this myself; seek advise from a professional of some sort. You'd certainly need the right parts and engineering to make it work. And it is probably just be easier and cheaper to do the shed route. And your insurance company might very well not give a hoot no matter how well it is done.

Just saying, it isn't as inherently dangerous as folks are making it out to be.

Golfview
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Re: Garage Generator Install

Post by Golfview » Thu Nov 14, 2019 6:59 pm

I would check the township first then check with my insurance company!

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onthecusp
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Re: Garage Generator Install

Post by onthecusp » Thu Nov 14, 2019 8:55 pm

Even the idea of running it inside a dedicated shed is problematic with respect to carbon monoxide. The vent idea with a fan assist just moves the failure point to the fan. A small shed with wide open doors, and a CO detector check before entering could work for temporary use.

Gill
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Re: Garage Generator Install

Post by Gill » Thu Nov 14, 2019 9:10 pm

firedawgy wrote:
Thu Nov 14, 2019 9:03 am
FROG, Finished Room Over the Garage
Must be real estate agent lingo...
Gill
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Re: Garage Generator Install

Post by jabberwockOG » Thu Nov 14, 2019 11:30 pm

Do not install a whole house electric generator without pulling a permit, insure to install per local code, and have the install inspected by your local town or county inspector. Doing otherwise might accidentally kill you and your family and might render your home insurance null and void should something go wrong in the future.

chipperd
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Re: Garage Generator Install

Post by chipperd » Fri Nov 15, 2019 6:07 am

fallingeggs wrote:
Thu Nov 14, 2019 6:52 pm
I'm going to go the other way and suggest that it is entirely possible to, in theory, safely route the exhaust outside of the house. Motor and sailboats of all sizes do this with their inboard engines and generators. But these are diesel, which isn't combustible, but they still store and use propane on-board. In addition to venting the exhaust, you'll need sensors to turn everything off if a propane leak is detected; again, something every boat has.

I just wouldn't try to do this myself; seek advise from a professional of some sort. You'd certainly need the right parts and engineering to make it work. And it is probably just be easier and cheaper to do the shed route. And your insurance company might very well not give a hoot no matter how well it is done.

Just saying, it isn't as inherently dangerous as folks are making it out to be.
Op didn't ask if this was possible, which it is from an engineering standpoint, but rather if this was "acceptable". Seems like you are implying it's not acceptable as you "wouldn't try to do this.." yourself.

Valuethinker
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Re: Garage Generator Install

Post by Valuethinker » Fri Nov 15, 2019 6:18 am

firedawgy wrote:
Thu Nov 14, 2019 7:56 am
[Split to new topic -- mod oldcomputerguy]

I know this issue has been beat to death but I would like to get an input on my idea. #1 running this generator outside would be a very tough task, so have been crunching ideas to install it in the garage. I have standard 3br house, attached garage with FROG. I have a 8800w generator I planned on running off natural gas. Planned on building a generator box in the corner of the garage, with a large fan installed on the garage side of the box to push the generated heat thru a vent out the side of the house, now for the kicker, the exhaust. Recently I upgraded my gas hot water heater to a gas tankless which has its own exhaust out the side of the house, so that leaves the old hot water heater exhaust out the ceiling to the roof. Whats your input on running the exhaust to that exhaust stack leading to the roof if I installed a inline fan at the bottom of the stack to push the exhaust up the stack? I would of course double wrap the exhaust to the stack with insulation to keep it safe and cool in the garage and install CO detectors in the house and garage. If this sounds acceptable any suggestion for a muffler. I think I have hit all the major safety points and would love the input from others here. Thanks all
The additional cost to do this in a way which was safe and to Code would probably kill the economics of doing this.

What's the issue with having a separate outside standalone generator & housing?

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Re: Garage Generator Install

Post by fru-gal » Fri Nov 15, 2019 6:22 am

I still don't understand why the OP can't have the generator outside, or even what type of generator it is.

I have a Generac 16kw natural gas automatic on off generator installed outside. The installers put it on a concrete pad offset from the outside of the garage. The only problem is it's noisy when running, but I have seen those noise dampening half enclosures people posted about that reportedly work well. I don't have enough room for one of those or I'd do that as well. I shovel snow away when necessary.

My blood ran cold when I read about the apartment over the garage. I have heard of people dying in such apartments when someone commits suicide by using car exhaust in the garage, inadvertently taking a family member in the upstairs apartment with him.

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Re: Garage Generator Install

Post by Valuethinker » Fri Nov 15, 2019 6:45 am

fru-gal wrote:
Fri Nov 15, 2019 6:22 am
I still don't understand why the OP can't have the generator outside, or even what type of generator it is.

I have a Generac 16kw natural gas automatic on off generator installed outside. The installers put it on a concrete pad offset from the outside of the garage. The only problem is it's noisy when running, but I have seen those noise dampening half enclosures people posted about that reportedly work well. I don't have enough room for one of those or I'd do that as well. I shovel snow away when necessary.

My blood ran cold when I read about the apartment over the garage. I have heard of people dying in such apartments when someone commits suicide by using car exhaust in the garage, inadvertently taking a family member in the upstairs apartment with him.
I missed that re apartment upstairs.

Yes. CO poisoning. Or fire. In fact I know someone this happened to.

The generator housing should be able to fit quite tightly to the generator (sound baffles). Just for the sheer improvement in one's own condition + that of neighbors it would be worth it.

Mr. Rumples
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Re: Garage Generator Install

Post by Mr. Rumples » Fri Nov 15, 2019 8:16 am

I am looking into a generator and have explored some options. Putting it into a closed environment is illegal where I live; distance from the house is regulated.

Not exactly related, but somewhat is the negligence question if there is a fire and a neighbor's property is damaged. A few weeks ago during the drought and a prohibition on outdoor burning, a few houses down the right of way which is a large field, my neighbor started a fire which got out of control. Not only is his homeowner's not covering his damage to his garage, but he has to pay a $500 fine to the fire department in addition to the costs of the equipment being brought out and he most likely will be sued by a neighbor whose garage was damaged by smoke if he doesn't pay for repairs. In short, do it by the book and to Code or there could be all types of unforeseen consequences.

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Re: Garage Generator Install

Post by lazydavid » Fri Nov 15, 2019 2:28 pm

onthecusp wrote:
Thu Nov 14, 2019 8:55 pm
Even the idea of running it inside a dedicated shed is problematic with respect to carbon monoxide. The vent idea with a fan assist just moves the failure point to the fan. A small shed with wide open doors, and a CO detector check before entering could work for temporary use.
I think you are conjuring the wrong image when reading the word "shed". A generator shed is typically nothing like a garden shed, but more like a large "deck box". It is typically large enough for the generator and not much else. Something like this: https://www.samsclub.com/p/keter-premie ... roduct_1_6

Mine is somewhat larger than that, but still not big enough that I can get in there with the generator and close it up. Besides, by the time I lift off the roof, which releases the front doors, and then open both of those to actually get access, CO would dissipate extremely quickly--whatever was remaining that hadn't left through one of the 24x24" vents I installed on either side (one with the fan on it).

This is the one I use: https://www.amazon.com/Lifetime-Product ... B01BHMKTAU

Broken Man 1999
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Re: Garage Generator Install

Post by Broken Man 1999 » Fri Nov 15, 2019 2:35 pm

Aren't these deck boxes made of plastic/resin? Do you just store the generator in the box when not in service, and remove when operating?

I can't see how one could run a generator in such a box, but maybe I am misunderstanding.

Broken Man 1999
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lazydavid
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Re: Garage Generator Install

Post by lazydavid » Fri Nov 15, 2019 3:43 pm

Broken Man 1999 wrote:
Fri Nov 15, 2019 2:35 pm
Aren't these deck boxes made of plastic/resin? Do you just store the generator in the box when not in service, and remove when operating?

I can't see how one could run a generator in such a box, but maybe I am misunderstanding.
Yes they are made of resin, polyethylene in my case. I've cut in 24x24" vents (standard return registers like you'd see in your house) on either end for cross-ventilation, with a 24" box fan mounted on the right (exhaust) side. This keeps the generator cool, provides clean combustion air, and vents the exhaust. I've measured on both cold and warm days, and the temperature inside the shed never gets more than 10F above ambient with the generator running under load. Usually it's within 2-3 degrees.

Some people weld an extension onto the exhaust pipe, and put it through a piece of fireproof cement-board where it exits the shell, but my solution seems to work well enough for me.

Broken Man 1999
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Re: Garage Generator Install

Post by Broken Man 1999 » Fri Nov 15, 2019 3:52 pm

lazydavid wrote:
Fri Nov 15, 2019 3:43 pm
Broken Man 1999 wrote:
Fri Nov 15, 2019 2:35 pm
Aren't these deck boxes made of plastic/resin? Do you just store the generator in the box when not in service, and remove when operating?

I can't see how one could run a generator in such a box, but maybe I am misunderstanding.
Yes they are made of resin. I've cut in 24x24" vents (standard return registers like you'd see in your house) on either end for cross-ventilation, with a 24" box fan mounted on the right (exhaust) side. This keeps the generator cool, provides clean combustion air, and vents the exhaust. I've measured on both cold and warm days, and the temperature inside the shed never gets more than 10F above ambient with the generator running under load. Usually it's within 2-3 degrees.

Some people weld an extension onto the exhaust pipe, and put it through a piece of fireproof cement-board where it exits the shell, but my solution seems to work well enough for me.
Thanks! You sound like you nailed it.

Interesting. I honestly wouldn't have thought of doing that. Now I have an idea, and sometimes my ideas are dangerous! :oops:

If I did such a setup, the generator could stay outside and still be completely protected from the elements. I probably would still prefer to plug it in, and hook up the gas only when about to use. I keep the generator on a trickle charger so we can easily crank without worrying about a dead battery. And, it just so happens I have an electric outlet within a couple of feet of where we stage the unit.

Broken Man 1999
“If I cannot drink Bourbon and smoke cigars in Heaven than I shall not go. " -Mark Twain

lazydavid
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Re: Garage Generator Install

Post by lazydavid » Fri Nov 15, 2019 4:16 pm

Broken Man 1999 wrote:
Fri Nov 15, 2019 3:52 pm
If I did such a setup, the generator could stay outside and still be completely protected from the elements. I probably would still prefer to plug it in, and hook up the gas only when about to use. I keep the generator on a trickle charger so we can easily crank without worrying about a dead battery. And, it just so happens I have an electric outlet within a couple of feet of where we stage the unit.
That's essentially what I do. Mine is gasoline-powered, so no connecting/disconnecting gas lines for me, but that would totally work. If I was using Natural Gas, I'd probably hard-pipe it and then install a valve, rather than using a hose. This is how my gas grill and pool heater are set up.

My shed is also right next to a double-gang box, so I pulled a cable from that box into the shed, and wired that into a weatherproof single-gang box on the inside, which is mounted to one of the horizontal support beams on the back wall. It didn't really have to be weatherproof, since it's protected from the elements anyway, but I figured why not. My battery tender is plugged into that, and hardwired (ring terminals) to the generator's battery. I'm planning to install a light in there, but haven't gotten around to it yet.

To connect it to the house, I leave this cable coiled up in front of the generator, plugged into itself to keep the contacts clean. That then gets plugged into the generator's 240V outlet, run through a hole I drilled in the side wall that is protected by a weatherproof-in-use receptacle cover similar to but not as nice as this one, and run across the yard to the power inlet mounted to the side of the house. That inlet is connected to a 30A breaker, which is equipped with an interlock to prevent both it and the main breaker from being in the ON position at the same time.

Broken Man 1999
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Re: Garage Generator Install

Post by Broken Man 1999 » Fri Nov 15, 2019 4:27 pm

lazydavid wrote:
Fri Nov 15, 2019 4:16 pm
Broken Man 1999 wrote:
Fri Nov 15, 2019 3:52 pm
If I did such a setup, the generator could stay outside and still be completely protected from the elements. I probably would still prefer to plug it in, and hook up the gas only when about to use. I keep the generator on a trickle charger so we can easily crank without worrying about a dead battery. And, it just so happens I have an electric outlet within a couple of feet of where we stage the unit.
That's essentially what I do. Mine is gasoline-powered, so no connecting/disconnecting gas lines for me, but that would totally work. If I was using Natural Gas, I'd probably hard-pipe it and then install a valve, rather than using a hose. This is how my gas grill and pool heater are set up.

My shed is also right next to a double-gang box, so I pulled a cable from that box into the shed, and wired that into a weatherproof single-gang box on the inside, which is mounted to one of the horizontal support beams on the back wall. It didn't really have to be weatherproof, since it's protected from the elements anyway, but I figured why not. My battery tender is plugged into that, and hardwired (ring terminals) to the generator's battery. I'm planning to install a light in there, but haven't gotten around to it yet.

To connect it to the house, I leave this cable coiled up in front of the generator, plugged into itself to keep the contacts clean. That then gets plugged into the generator's 240V outlet, run through a hole I drilled in the side wall that is protected by a weatherproof-in-use receptacle cover similar to but not as nice as this one, and run across the yard to the power inlet mounted to the side of the house. That inlet is connected to a 30A breaker, which is equipped with an interlock to prevent both it and the main breaker from being in the ON position at the same time.
Nice setup. Especially since you have set it up to also protect power company workers. I cringe a little when I read posts where protecting the workers depends on remembering to manually set things up. Nice thing with ours is we have a transfer panel, and DW can handle the activation so easily. The only thing she needs help with is rolling the generator out, and plugging in the power and L.P. hose. We have neighbors who do that for us, so we are really blessed.


Broken Man 1999
“If I cannot drink Bourbon and smoke cigars in Heaven than I shall not go. " -Mark Twain

Wellfleet
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Re: Garage Generator Install

Post by Wellfleet » Fri Nov 15, 2019 5:41 pm

The only safe and legal way to do this would be to hire a MEP mechanical/plumbing/electrical engineer to design the project in compliance with local code.

These are built every day in commercial buildings, however always specifically designed!!!

Do not attempt current project!!

Erwin007
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Re: Garage Generator Install

Post by Erwin007 » Fri Nov 15, 2019 5:54 pm

samsoes wrote:
Thu Nov 14, 2019 8:57 am
firedawgy wrote:
Thu Nov 14, 2019 7:56 am
I have standard 3br house, attached garage with FROG.
What is FROG? (Assuming, of course, it's not an amphibian.)
It stands for Finished Room Over Garage. It’s a southeastern US thing (or at least was very prevalent in South Carolina when we bought a house there). It’s basically what other parts of the US call a bonus room, or a media room.

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dratkinson
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Re: Garage Generator Install

Post by dratkinson » Fri Nov 15, 2019 5:59 pm

Be aware of vermin when storing engines outside. Mice like to build nest in the engine cooling shroud over the winter. And from there they gnaw on the wires, and urinate on and corrode electrical connections. (Known problem on garden tractor forums.)

I bought a snowblower off CL---owner started, demo'd it, good to go. Got it home and was checking it over, opened bottom to check condition of wear on Uni-trol replaceable rubber disk and found a nest and dead mice. They must have moved in there for winter and died when owner used it to clear snow.

So ensure your outside enclosure is vermin proof. And as a CYA, check cooling shroud before using it.



My portable generator lives in the garage and works outside under the far edge of an open covered patio---keeps most of the weather off while in operation---and connects to house through single 240v whole-house transfer switch. Takes ~15 min to set up. I use a Kill-A-Watt meter to manage my power budget; I assume I'm okay if voltage remains >113v. But wish it were whole-house NG automatic.

Haven't had a serious power outage since getting it. (Knock on wood.)



OP was planning to use existing exhaust flue. I had a chance to talk to city about reusing installed exhaust flues.

Exhaust flue size. I learned that exhaust flues are sized to vent by installed BTU capacity. A too large flue will allow the exhaust to cool too much, acidic condensation will corrode metal flue and allow combustion byproduct to leak into home. A too small flue will not properly vent and allow combustion byproducts to spill into home.

So flue must be sized to fit installed appliances. Code will not allow the exhaust flue to be too big, too small, or the addition of additional NG appliances that exceed flue BTU capacity. (It's also difficult and expensive to install a larger exhaust flue.)


In my case, my exhaust flue is sized for my basement NG forced-air central heat + NG standing-pilot tank-type water heater. I wanted to add a millivolt-powered NG backup heater, tied to same exhaust flue, and use transfer vents in basement ceiling to heat the upper floor by thermosyphon loop during a power outage.

City: No, you will exceed BTU capacity of installed exhaust flue.
Me: But, but, ...during a power outage, the central heat will be off, those BTUs will not be used.
City: You know this. We know this. But some idiot will try to use the backup heater with the central heat, exhaust flue BTU capacity will be exceeded, exhaust products will spill into basement, and CO will kill him.

Codes are to protect the idiots.

The city also has rules for required air flow into an area containing a combustion appliance---can't be installed behind a closed door.

Bottom line. If I ever build a home, I will size combustion vents (intake and exhaust) for all NG appliances, including a backup heat source. It's on my list. :)
d.r.a., not dr.a. | I'm a novice investor, you are forewarned.

fru-gal
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Re: Garage Generator Install

Post by fru-gal » Sat Nov 16, 2019 8:02 am

Valuethinker wrote:
Fri Nov 15, 2019 6:45 am

The generator housing should be able to fit quite tightly to the generator (sound baffles). Just for the sheer improvement in one's own condition + that of neighbors it would be worth it.
I'm a little confused. The enclosure (not sure if that's the correct word) of my generator has some sound insulation lining some of its walls, but not enough to keep the generator from being a noise nuisance. Adding more, according to Generac, voids the warranty.

Or, are you taking about something built around the generator?

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onthecusp
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Re: Garage Generator Install

Post by onthecusp » Sun Nov 17, 2019 1:41 am

lazydavid wrote:
Fri Nov 15, 2019 2:28 pm
onthecusp wrote:
Thu Nov 14, 2019 8:55 pm
Even the idea of running it inside a dedicated shed is problematic with respect to carbon monoxide. The vent idea with a fan assist just moves the failure point to the fan. A small shed with wide open doors, and a CO detector check before entering could work for temporary use.
I think you are conjuring the wrong image when reading the word "shed". A generator shed is typically nothing like a garden shed, but more like a large "deck box". It is typically large enough for the generator and not much else. Something like this: https://www.samsclub.com/p/keter-premie ... roduct_1_6

Mine is somewhat larger than that, but still not big enough that I can get in there with the generator and close it up. Besides, by the time I lift off the roof, which releases the front doors, and then open both of those to actually get access, CO would dissipate extremely quickly--whatever was remaining that hadn't left through one of the 24x24" vents I installed on either side (one with the fan on it).

This is the one I use: https://www.amazon.com/Lifetime-Product ... B01BHMKTAU
OK, I see now. That would work great.

Valuethinker
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Re: Garage Generator Install

Post by Valuethinker » Sun Nov 17, 2019 12:18 pm

fru-gal wrote:
Sat Nov 16, 2019 8:02 am
Valuethinker wrote:
Fri Nov 15, 2019 6:45 am

The generator housing should be able to fit quite tightly to the generator (sound baffles). Just for the sheer improvement in one's own condition + that of neighbors it would be worth it.
I'm a little confused. The enclosure (not sure if that's the correct word) of my generator has some sound insulation lining some of its walls, but not enough to keep the generator from being a noise nuisance. Adding more, according to Generac, voids the warranty.

Or, are you taking about something built around the generator?
The latter. Ones I have seen are a box with sound baffles. Can drop sound by 10 DB I think.

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firedawgy
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Re: Garage Generator Install

Post by firedawgy » Mon Nov 18, 2019 8:53 am

I appreciate all the inputs and it pretty much confirmed that its not worth the risk. I would like to ad that if you would like to respond to me or anyone else with your input please read and understand the entire posted statement. Several people here stated that I could not combine my hot water heater and generator exhaust, what I actually said that the original water heater was change to a tankless and it had its own exhaust, leaving the original stack solo. Several comments about the room over the garage and obviously if you don't understand what that is or how exhaust ducts off a gas water heater then you really don't understand and shouldn't comment. Anyway I appreciate the comments from the ones that understood what I was asking and I think I'll shoot for the exterior install, though it will be a [pain -- mod oldcomputerguy].

smitcat
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Re: Garage Generator Install

Post by smitcat » Mon Nov 18, 2019 9:27 am

firedawgy wrote:
Mon Nov 18, 2019 8:53 am
I appreciate all the inputs and it pretty much confirmed that its not worth the risk. I would like to ad that if you would like to respond to me or anyone else with your input please read and understand the entire posted statement. Several people here stated that I could not combine my hot water heater and generator exhaust, what I actually said that the original water heater was change to a tankless and it had its own exhaust, leaving the original stack solo. Several comments about the room over the garage and obviously if you don't understand what that is or how exhaust ducts off a gas water heater then you really don't understand and shouldn't comment. Anyway I appreciate the comments from the ones that understood what I was asking and I think I'll shoot for the exterior install, though it will be a [pain -- mod oldcomputerguy].
Hello Firedawgy -
I believe you have some pretty good feedback from this site even though it is primarily for financial issues.
While searching for additional insight regarding your proposed genset install you will likely find them at constructions websites, genset manufacturers sites as well as getting great inputs from your local architects , your local fire department and your local building departments.
Dependent upon your location and the specific details your potential options will likely vary considerably.

jwtietz
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Re: Garage Generator Install

Post by jwtietz » Mon Nov 18, 2019 9:40 am

I did a generator shed. Works well and it just stays in there. Not a cheap option but better than risking the safety of the family. There are plenty of designs but here is just one- https://www.youtube.com/watch?v=W_Pfc8TMF_8

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