I have the "deluxe" (what they call it) cab on my National, well built, nice and quiet inside, with a heater but no AC. The other day when it hit 104 inside despite strategically located shade cloth, all the windows and door open, and both fans going, I said "screw this." It never occurred to me to order whatever factory setup National offers, probably because it'd take too long to get plus cost a lot. So, here is what I've come up with so far.
A $129.00 5,000 BTU AC unit, including freight. A 1000 watt Yamaha inverter generator, $761.00, delivered. Both prices include Idaho state sales tax, as Amazon is now collecting that. If ever audited, as I am of course claiming this as a expense of the business, it will be nice to have the record showing the tax was paid, they have closed that loophole! A skinny wheel was used to cut through the cab sheeting, which is 3/16" thick, National does not mess around, no wonder it's so quiet in there, good counter weight too of course. A simple platform using stuff I had in the shop holds the thing in place, plus the flanges are pop riveted to the AC unit and screwed to the cab wall using self tapping metal roof screws I had left over from building my crane shed. It's also strapped down, just to avoid any movement whatsoever.
A chunk of scrap deck plate that used to be part of my home hydro electric intake system was used to provide a platform for the little gen set. I went Yamaha instead of Honda as it was almost 2 lbs lighter and just a hair quieter in operation, both are very highly regarded, this one will run 12 hours on a half gallon of gas at about 30% load. I can afford that as if it's being used it means I'm working, ha ha. I'll only use pure mo gas in it, the same I use in my plane, it stores a lot better long term then E-10. It will be quickly removable, in case I need to leave the rig at a job site over night, it will easily fit in one of my lockable rigging boxes.
So, it's all done (the pic of the gennie shows it before it was secured, also before the cord was secured so it doesn't end up in the ring gear), and I've run it up and it all works. BUT, especially as it was in the shade of my building, I was a little surprised to see it didn't cool off the cab quicker. It was 89 when I turned it on high, (plugged into my shed's power system, which is solar powered, so free) and I went into town for a couple hours, it was 71 when I got back. With the sun beating in when in actual use, I am starting to have second thoughts about the selection of the 5,000 BTU unit. I expected (don't ask me why) to be pretty much run out of there by the cold, if anything I thought even this small unit would be over sized for as small as the cab is. I did not have the cab fans on, that should help stir things up a bit better perhaps. Monday will be my first real use on the job, I have a 2 hour drive then 4 or 6 hours of work. Since I already have a 2500 watt inverter on board, I plan to "pre cool" it as I drive down the road, using an extension cord strung out on the truck bed from the inverter location next to the Mack's batteries, then I'll switch over to the gennie. This AC only uses 300 to 400 watts, and I at first thought to use only the inverter, saving the cost of the gennie, but couldn't get around how to get the line power into the cab without somehow creating more problems then it would be worth. Plus, I've been looking for an excuse to pick up one of these little generators, for my winter time airplane trips (preheating the engine) and also when on camping trips with my electric mountain bikes. Anyone else cobble up a system such as this, I believe I saw where someone did here but can't find it.....how big a AC unit does it take to provide LOTS of cooling RIGHT NOW? I may upgrade to a 8,000 BTU unit, if this fails the real world test, still within the gennie's capabilities.
A $129.00 5,000 BTU AC unit, including freight. A 1000 watt Yamaha inverter generator, $761.00, delivered. Both prices include Idaho state sales tax, as Amazon is now collecting that. If ever audited, as I am of course claiming this as a expense of the business, it will be nice to have the record showing the tax was paid, they have closed that loophole! A skinny wheel was used to cut through the cab sheeting, which is 3/16" thick, National does not mess around, no wonder it's so quiet in there, good counter weight too of course. A simple platform using stuff I had in the shop holds the thing in place, plus the flanges are pop riveted to the AC unit and screwed to the cab wall using self tapping metal roof screws I had left over from building my crane shed. It's also strapped down, just to avoid any movement whatsoever.
A chunk of scrap deck plate that used to be part of my home hydro electric intake system was used to provide a platform for the little gen set. I went Yamaha instead of Honda as it was almost 2 lbs lighter and just a hair quieter in operation, both are very highly regarded, this one will run 12 hours on a half gallon of gas at about 30% load. I can afford that as if it's being used it means I'm working, ha ha. I'll only use pure mo gas in it, the same I use in my plane, it stores a lot better long term then E-10. It will be quickly removable, in case I need to leave the rig at a job site over night, it will easily fit in one of my lockable rigging boxes.
So, it's all done (the pic of the gennie shows it before it was secured, also before the cord was secured so it doesn't end up in the ring gear), and I've run it up and it all works. BUT, especially as it was in the shade of my building, I was a little surprised to see it didn't cool off the cab quicker. It was 89 when I turned it on high, (plugged into my shed's power system, which is solar powered, so free) and I went into town for a couple hours, it was 71 when I got back. With the sun beating in when in actual use, I am starting to have second thoughts about the selection of the 5,000 BTU unit. I expected (don't ask me why) to be pretty much run out of there by the cold, if anything I thought even this small unit would be over sized for as small as the cab is. I did not have the cab fans on, that should help stir things up a bit better perhaps. Monday will be my first real use on the job, I have a 2 hour drive then 4 or 6 hours of work. Since I already have a 2500 watt inverter on board, I plan to "pre cool" it as I drive down the road, using an extension cord strung out on the truck bed from the inverter location next to the Mack's batteries, then I'll switch over to the gennie. This AC only uses 300 to 400 watts, and I at first thought to use only the inverter, saving the cost of the gennie, but couldn't get around how to get the line power into the cab without somehow creating more problems then it would be worth. Plus, I've been looking for an excuse to pick up one of these little generators, for my winter time airplane trips (preheating the engine) and also when on camping trips with my electric mountain bikes. Anyone else cobble up a system such as this, I believe I saw where someone did here but can't find it.....how big a AC unit does it take to provide LOTS of cooling RIGHT NOW? I may upgrade to a 8,000 BTU unit, if this fails the real world test, still within the gennie's capabilities.
