Idle or Not to Idle?

I will idle below 20-25 or if its above 80ish depending on humidity. Most of the owner /ops I know are pretty careful about idling. Having said that.......I am not on the APU bandwagon. I don't want to deal with one. MOST weekends I am home, so the appeal for me just isn't there.

 

I have never been able to justify an APU. I do use a Webasto bunk heater in the winter that does a good job, but I stay in the upper midwest all year, and maybe, I idle a week or two of days in the summer because it is too warm. Otherwise window screens and a 12v fan do the trick most other times. I figured that if I spent for a full blown APU, it would take somewhere well over a decade just to break even at best. I go home on the weekend, so I am not going to be sitting in a truck for 34.

For those going the portable generator route, you can get a Yamaha portable that will run tri-fuel... NG, Propane, or Gasoline... which ever you want, whenever you want. And a person can carry, legally, a heck of lot more propane than gasoline and easier to deal with.

http://www.yamaha-propane-natural-gas-generators.com

And one can get a custom box to mount on rail.....

http://www.hayesequipment.com/hayes_products.htm

 

I have one and they are over rated and a pain in the ###..

 

I have a HP2000 APU which runs on a 2 cylinder Perkins engine. It keeps my batteries charged when the truck isn't running and runs my 2500 watt inverter and microwave over. When operating, the APU uses 1/10 of a gallon per hour or 1 gallon during a 10 hour break. I bought it two years ago and I would say it has already paid for itself. The cost was $8000 installed. Oil and filter changes cost about $50 at TA/Petro which I do about every 600 hours.

 

I have been on the fence about buying an apu. We don't stay OTR long enough to be doing 34 resets in the truck, so like a few others, we're not seeing the run-time to get the fuel savings advertised by the apu manufacturers.

However, my new to me truck came with a TK tripak. I was spoiled rotten with it the first trip out. Since it has 24k+ hours on it, it may have even been installed used. If they're supposed to come with an inverter, I either haven't stumbled across it (surely I'd see something like that after a month!) or the previous owner took it. Don't really care. I run few accessories off a 175w sine-wave inverter off a 12v lighter socket. Basically chargers for my gadgets, a all-in-one printer, and a small fan. I've considered upgrading to a larger inverter, but to be honest I could get by with a quality 12v cooler since we're only out a few days at a time.

As with any used equipment it was in poor state of maintenance. I did the PM on the power unit, no big deal. The exhaust pipe for the heater was rusted out so I replaced that to be safe. I didn't like smoke rising under the bunk, even though there was no signs or odor that it was getting inside. The heater also signals a new pope election now and then, so I need to take the heater apart and clean it out and replace the glow pin screen. One of these days. Thanks MN - my belt squeals a little when first started. I just haven't bothered to check it out yet. Next time the cover's off LOL.

My first trip out, the cobblestone path known as I-20 thru Shreveport shook the muffler off. That was fun since I haul a reefer. If the neighbors were unhappy with the big Carrier purring away, I'm sure they enjoyed the hotrod apu sound harmonizing. Being the good neighbor I am, the muffler was replaced that following weekend. It was not gold plated and monogrammed as the price would suggest. Back to it's normal put-put noise at any rate.

The a/c was a little flat so I took my r134a gauges out to the truck and charged a few cans in. The service ports were not covered and pointed forward, exposing them to all sorts of road spray and rusting them out and I'm pretty sure they're leaking. New caps will not even find threads. For now, the new caps are secured with zip-ties until I can replace those lines. It's a little low at the moment, but approaching 80º in Houston and Hammond, LA this week, the cab stayed comfortable in direct sunlight. At one point in the day I zipped the curtain for a nap and woke up freezing, since that effectively cut the volume to cool in half. Before it gets real hot, I will be spending a few bucks at TK for the a/c hoses and get it right.

All that plus the peace of mind of being able to leave my marker lights and other stuff on all night when parked without worrying about dead batteries. I'm sold.

Now just debating on whether my other truck will get a generator style apu (Dynasys) for less money (must run for heat and power), or save up the pennies for a used tripak. I don't have the bucks, nor do I want another loan payment for a new one.

I can see where others don't see the value with an apu. And some others will cobble up a genset of some sort with accessory a/c heat and power. To each his own. On the former, the sting of a $14k in-frame still makes me cringe knowing that truck is idling for comfort plus added fuel consumed. On the latter, the piecemeal solution is too fiddly for me. I would rather pay a little more for the convenience of automation and not rigging a generator or hauling gasoline.

On the idle question, I did disable the auto-shutdown option in my ecm. I don't idle much, but shutdown is annoying. For example when wanting to keep the air pressure charged for tire filling or air tools. I do shut down when stopped for more than a few minutes, such as fueling or checking in at a shipper.

 

I got my TK apu three years ago best money ever spent. Service is every 1000 hours in three years done three oil changes that it. Paid 8700 installed at Detroit MI TK. Use it about three to four nights a week at this rate it was paid for in two years. The first year I cut 897 gallons fuel for the year. The second year cut 980 gallons of fuel. If I sell my truck will move it to the next truck. I to have a cummins ISX and know for a fact it burn a gallon hour at idle not by dash but done by pencil and paper. Also had the arctic package installed. It keeps the engine warm to 100 in the winter and battery at 12 volts use this mode on weekends at home in winter. Also have 2500 watt inverter to power ac stuff. Then there is the espar heater. the TK unit cycles on and off only if battery goes below 12 volts or when AC is on only when the compressor needed to keep the temperature at set point. I was truly amazed at the fuel saving was understated by allot.

 

Also forgot the first 3 months I had apu I was in FL in July my truck AC busted a AC line. I just ran the apu the whole time got my back to MI to get the repairs done at home. Also saved me another time had battery go bad started apu up it got my truck started to get to the truck stop to get a battery. Have been told if your alternator goes out run the apu will get you home or to the shop.

 

FYI - electric heaters are cheap and quiet, mine is a quartz, radiant type deal which fits nicely below my bunk. Keeping the engine warm is as simple as plugging in the block heater. Installation is much simpler than an APU, but the real clincher for me is how quiet it is. fugliness of a roof-mounted AC is in the eye of the beholder I guess, mine is no show truck to begin with so it certainly isn't an issue for me. Another argument for the gen is that generator has value and usability on or off the truck, an APU is more or less married to the truck, very expensive to transfer to another truck and you certainly aren't going to be using it when the power goes out in your house, etc... I keep mine in a 24x24x48 sidebox right now and chain and padlock it to the frame when in use. I have to remove the gas cap and wiggle it a bit to get it in that box, very tight. planning to mount it to the frame, it's more or less "in a box" as it is.

 

and to get any benefit of it, you must start it and run it.


Kind of like cows, a topic that will always be chewed on like cud.

 

i would think you would need better ventilation then that box pictured above.

i mean. that box would fill up with exhaust faster then it could suck in fresh air to make the generator run. unless there was a hole in that box somewhere not showing in the picture for the exhaust to flow out.