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McDennys
November 19th, 2008, 06:59 PM
Hello all,
I am very new to this forum and want to thank you for letting me join. I recently purchased a standby generator by Generac Guardian. It also has a 200 amp auto transfer switch. I live in Lebanon, Maine and we tend to lose power alot.
The house is designed with a walk out basement, over the basement I have a 12 x 40 deck which connects to the farmers porch. My electrical is run underground from a pole about 120' away from the house. The meter is mounted to the wall under the deck and just goes through to attach to my 200 amp panel. I would like to install the generator near the meter, but this would be under my deck, and I have read several times, "not under a wood structure", I have seen the questions asked here in the forums, but never really answered. The top of the generator would be atleast 5' from the bottom of the deck. I do have rock retaining wall on both sides of the basement. I could keep the generator away from my basement window, or 5 ' away from the house.
I would also have to run the propane line 75' or so to reach the generator. I was planning on running it into conduit along the bottom of the house and under the deck and down to the generator.
I will gladly take pics if it would help. I am just trying to avoid alot of underground work, and it would be nice if I could mount it under my deck and it be OK.





Any thoughts?

Thanks,
Dennis

yucan2
November 19th, 2008, 07:35 PM
Hello all,
I am very new to this forum and want to thank you for letting me join. I recently purchased a standby generator by Generac Guardian. It also has a 200 amp auto transfer switch. I live in Lebanon, Maine and we tend to lose power alot.
The house is designed with a walk out basement, over the basement I have a 12 x 40 deck which connects to the farmers porch. My electrical is run underground from a pole about 120' away from the house. The meter is mounted to the wall under the deck and just goes through to attach to my 200 amp panel. I would like to install the generator near the meter, but this would be under my deck, and I have read several times, "not under a wood structure", I have seen the questions asked here in the forums, but never really answered. The top of the generator would be atleast 5' from the bottom of the deck. I do have rock retaining wall on both sides of the basement. I could keep the generator away from my basement window, or 5 ' away from the house.
I would also have to run the propane line 75' or so to reach the generator. I was planning on running it into conduit along the bottom of the house and under the deck and down to the generator.
I will gladly take pics if it would help. I am just trying to avoid alot of underground work, and it would be nice if I could mount it under my deck and it be OK.





Any thoughts?

Thanks,
Dennis

Dennis

Your particular concerns would best be answered by your local licensed electrician that is familiar with your local codes.

However, its true that Generac is comfortable with a 4 foot clearance above the unit but your local electrical inspector may not be.

Without seeing a picture, you mentioned walls on (2) sides? And I assume the exit/entry door being the 3rd wall? You're in Maine. Picture this: The deck covered with snow, the generator running due to one of your frequent power outages and the unit enclosed now from above, because of the snow and on the sides by 2, according to your description, or 3 sides by my understanding. Not a good scenario at all. If there is an open window inside this nature created cave with the just rightly or (wrongly) prevailing winds, this could be a recipe for disaster.

But then why would the window be open in the winter?:)

Just food for thought.

SkipD
November 19th, 2008, 08:08 PM
NFPA 37 (and other national codes) and (in many case more importantly) local codes (I'm not referring to electrical codes, and an electrician may have no clue about clearance codes) will dictate minimum clearances from a generator (or any other stationary engine) to walls, combustible materials, and wall openings. The 2006 version of NFPA 37 (the latest one I can find on the web to read without buying the publication) stated a minimum of five feet in any direction (including above) to any combustible material.

In addition, and perhaps more importantly, the 2006 version of NFPA 37 spells out a requirement for a 5-foot minimum spacing between the generator and any opening in the nearby walls (windows, doors, or any other opening that engine exhaust could possible enter the occupied building through). There are a number of state/local codes that extend this minimum dimension to ten feet.

SkipD
November 19th, 2008, 10:53 PM
Quite honestly, I don't see anywhere under the deck that would be safe for a stationary engine such as that in a generator.

It appears to me that the exhaust from the engine could easily find its way into the doors and/or windows in the area under the deck. There does not seem to be a place to get the generator far enough away from wall openings. I would also guess that there's not a lot of air movement past the building walls in that area.

NYS SitePower Corp.
November 20th, 2008, 06:10 PM
Its tight under there. I agree that under the deck is not the place for it. I understand that while it may be easier to locate & install the generator, the potential harmful effects of CO2 buildup or possibly entering the house would be far worse than completing the extra work to make sure you're out in the open where the prevailing winds can keep the generator a) cool and b) well ventilated.

SkipD
November 20th, 2008, 06:17 PM
.....the potential harmful effects of CO2 buildup or possibly entering the house....
Dan, I suspect you meant to write CO and not CO2. ;)

SkipD
November 20th, 2008, 10:18 PM
Can I run them in the same trench as long as they are separate conduit?Dennis, I would suggest that you contact your local building inspector and have him/her find out the details of your local codes and/or national codes - whichever is more stringent.

Don't forget that you need at least four small wires for control of the transfer switch along with the three larger ones - 2 for power (any color other than green) and 1 for neutral (marked with white) - and a properly sized ground wire (green or bare).

It would also be a good idea to run a pair of 12-gauge wires (one colored anything but green and the other white) for 120V hot and neutral to enable installation of a 120V receptacle inside the generator housing just in case you want to power a battery charger and/or tools.

NYS SitePower Corp.
November 21st, 2008, 09:08 AM
Dan, I suspect you meant to write CO and not CO2. ;)

Can you tell that I got in after a long day in the cold? :D Nice catch, you're right. :cool: