Home Depot was selling off the Generac GP5500 last year so I bought one. I didn’t have a Shed or a Garage to store it in so I used a Suncast GS2500 to store it in when not needed.
After a while I thought about what it would take to run the generator inside the Suncast and this is what I ended up with after looking around the internet for ideas.
http://youtu.be/3s6IcmKv8XI
The issues to overcome were getting air in to the Generators engine, getting the heat and exhaust gases out.
I found a 10″ shuttered fan by Fantech (2SHE1021) on sale, but I’d recommend something larger if you plan on doing something similar. Amazon.com has the Fantech 12″
for $117 (cheaper than the 10″).
2″ Attic Vents (SKU # 388719) were mounted in the shed wall where the Generators Air Filter was located and I put the Fantech on the opposite side.
To get the exhaust routed to the outside I used various pieces from the HVAC Aisle (Item numbers are for Home Depot).
Speedi-Products 4 in. Round Galvanized Wall Vent with Spring Return Damper
Model # SM-RWVD 4 Internet # 202907283
(Photo is of an Aluminun one)
Frost King 3 in. x 25 ft. Foil Backed Fiberglass Pipe Wrap Insulation
Model # SP42X/16 Internet # 20226232 Store SKU # 710539
Deflect-o 8 ft. Semi-Rigid Duct
Model # A038/16 Store SKU # 185868
Master Flow 3 in. Round Duct Cap
Model # DC3 Internet # 100197348 Store SKU # 259913 Store SO SKU # 755578
The Magnet in the video below is 5685K33 from McMaster Carr.
http://www.youtube.com/watch?v=TbXiElx5J5s
To monitor the internal temperature I use a themometer from WalMart, its meant to display the outside and inside temperature but has a wireless remote sensor which I put inside the housing and can see the temperature on the Display in my House.
I also added a high temperature cut off to the built in low out cut off. That way if the fan stops working the temperature will increase but once it gets to the activation temperature of the Normally Open switch I purchased from eBay it will short the ignition coil to ground which cuts the engine. I have mine set to 50 Celcius, but comments on my video suggest I should go higher.
http://www.youtube.com/watch?v=KSTIbvAZlu0
I have installed a tri-fuel converter from US Carburation. Was wondering about the emergency cutoff switch because I am supposed to turn off the generator by turning off the propane; not the kill switch. Have you encountered this issue? It is my understanding the propane keeps running to the carb. unless you turn it off manually. I’m thinking this could be a problem. Thanks for the info.
Sorry for the delay (I havent been able to turn on notifications when someone replys and I dont often check here).
It seems like you would need a circuit that would detect the grounding of the ignition by the temperature sensor and would then trip a solenoid valve to turn off the propane. How to do that isn’t something I’ve looked into unfortunately.
In the “Step 1 Warning’s” section of this webpage –
http://www.instructables.com/id/Converting-a-generator-to-run-on-propane/
He does say that commercially available propane kit’s (which yours is) have an automatic shut off if they detect the generator has stopped so unless someone converts their old gasoline carb to propane it seems like its built in?
You would use a 24 or 28vac natural gas solenoid that is found on all home gas heaters, wired to a small plug transformer and plugged into the generator itself. Power goes out (ie: generator stops), the flow of propane stops. Plumb it in after the regulator.
Thanks for the idea & parts list. I located a magnet on eBay and with the end cap # I’ll be able to complete building the enclosure for my 7.5KW generator. With proper Watt management I can run everything in the house as we use propane for heat, hot water, cook, cloths dryer so the loads on the generator are just lights, motors (fans, refrigerator compressor) and TV. I build a transfer panel using 20A break berofe make three way switches, and an additional seperate circuit breaker panel. The common terminal of the three way switch goes to the load, “A” terminal goes (normal street power) “B” terminal goes to the (generator).
Instead of using dryer vent flex hose I used Walker Automotive Flexible Exhaust Hose Repair Kit Galvanized 3 Inch I.D. 18 Inch length. It can withstand the heat generated from the exhaust far better than dryer vent hose. Available @ Advance Auto & O’Reilly Auto Parts from $10-$15.
Gotta agree. My first trial run to see how the semi-rigid dryer exhaust hose works showed excessive smoking along the entire tube within a minute of starting up. And it got blazing hot quick. Gonna get some Walker flexpipe.
It’s impossible to find the 3 inch duct cap in-store in my area. Lowes, Home Depot and the local Ace all carry 4″ and up. Frustrating because that’s the only part I’m missing! I even found the 3″ magnet at Harbor Freight. I’ll probably have to order it online and pay 5 bucks shipping for a 3 dollar part…. Grrrrrrrr….
Ask at Home Depot, they may special order it for you so you don’t have to pay shipping.
It’s –
Model # DC3 Internet # 100197348 Store SKU # 259913 Store SO SKU # 755578
(I dont know how they order parts so I’d write all that down and take it).
I took it off this past spring when I changed the oil on generator and it was still magnetic. Sorry for the late response.
Thanks for the great information here. Appreciated.
On the generator enclosure you mentioned that you hope no one puts the enclosure next to their house or garage. I was curious what your reason for not putting it next to the house?
Carbon Monoxide Emissions could get into the house and they are deadly.
Greetings…do I understand you’re suggesting installing two fans and not one? wouldn’t a one 12″ Fantech be enough to do the job? would appreciate your feedback. Thanks.
Also, would appreciate it if you can share the type of exhaust fan you’ve used…the ones I’ve checked so far are in the range of $150…Thanks.
I used a 10″ FanTech, there should be links to them on Amazon within the post.
I used a single 10″ fan. A 12″ fan is what I’d recommend. I only went with the 10″ because I found it on sale.
Just curious, did you have a problem with insulation burning and wall of shed melting? used the same foil backed insulation you used on 3 inch flex
tubing and the same on the 4 inch dryer vent going thru the wall. the insulation got hot and burnt and the wall of shed started melting. I have a 5 inch hole in wall for the dryer vent. other than that I followed your directions. special liked your idea of the 125 degree shutoff switch. good thiinking
I didn’t have that issue at all, Perhaps a piece of the inner exhaust is touching the outer part conducting heat to the shed. Or you might just have a very hot Generator.
Thats pretty slick. Probably the best actual example of an enclosure I have seen, that actually works
how did you hook the power from the fan to the generator? It only came with a black and white wire, no 110v plug
you know what, just go ahead and ignore that. Found out how to make it work.
Any chance you got an answer to your question? Do you need a plug or can the generator provide the power?
I wired the 2 wires on the fan to a reuglar 2 prong plug using wirenuts. In the US and using a US plug the Black wire is hot (narrower pin on the plug), white is neutral (wider ping on the plug).