APU Questions

Bohemian

New Member
I have a few questions, but first some background. My wife is a Central Refrigerated/Swift lease op and I ride with her. We have a 2013 Cascadia.
We are exploring the possibility of buying an APU, but I need some info.
Do all APUs or only certain types keep the engine oil temps warmed in the winter so you don't have to idle?
How difficult are they to install or move from one truck to another?
What are the pros and cons of new vs used?
How much fuel does it save vs idling?
How much fuel will they save for team drivers vs solo drivers?
 

Injun

Rabid Squaw
Staff member
Supporter
As for engine warmer, I would suggest plumb the cooling systems together. The warmth of the coolant circulating from the APU will keep the engine warm. This can be done with any water-cooled APU.

@SkateBoard will tell you to get a RigMaster.
@mndriver will tell you get a TriPak.

Both have advantages and disadvantages. Skate and MN can run you through them.

There are other brands, but service locations may be difficult to find and/or get to.

Also, if Mrs Bohemian ends up not keeping the truck, she will not be able to take the APU. It will become property of IEL. She will still be responsible for paying it off. Keep this in mind when considering APU.

I run for Swift and have run for another company that had APUs on lease trucks. Even running OTR, I found the APU to be awesomely convenient, but not cost effective for business when all costs are weighed against fuel burned idling.
 

8978

** Commie Express **
Supporter
Do all APUs or only certain types keep the engine oil temps warmed in the winter so you don't have to idle?
No, some are plumbed into the coolant systems.Others have a real generator that puts out 120 volt and can power a block heater. There is no reason to heat an engine unless your batteries are bad. Every APU keeps the batteries charged so I wouldn't worry about keeping your engine warm

How difficult are they to install or move from one truck to another?
I've never installed one but I don't think I would attempt to. I'm sure I could do it but may not know the little secrets that professionals know that could get me in trouble.

What are the pros and cons of new vs used?
Same as buying a used car. It's a complete crap shoot.

How much fuel does it save vs idling?
How much fuel will they save for team drivers vs solo drivers?
I have a Rigmaster and it uses .2 gallons per hour. During the summer months it runs pretty much for my whole 10 hour break for the AC.

Given those figures and a truck using maybe .8 gallons per hour and fuel at $3.80

APU costs $7.60 to run for 10 hours
Truck costs $30.40 to run for 10 hours

You can do the math from there.
 

krelithous

Well-Known Member
Supporter
I personaly would not install anything on a lease truck unless it was mine and my names on the title!! is she willing to gamble away anywhere from 8,000- 17,000 if something goes wrong:confused-96:. my tri pak uses .28 gallons an hr. it heats and cools the cab keeps the engine warm monitors the batteries. the one downfall of the tri pak is it has a 1500 watt inverter!! and it's 17,000 :stare1:. if you wanna run something like a keurig machine then you'll need a higher wattage inverter since a keurig machine is like 1800 watts. I know they just redid the tri pak from the last model so I don't know how much the inverter is as far as power. are you allowed to carry a gen set :confused-96: as much as running cords into the truck and fueling the set set can and will get old but atleast your not out $$$$:stare1:
 

Injun

Rabid Squaw
Staff member
Supporter
Most of the time, cost/benefit calculations are done on the assumption the truck idles every minute it's not moving. I don't idle enough to justify the cost.
 

mndriver

curmudgeon extraordinare
Supporter
buy what you can afford.

Skateboard is sold on his Rigmaster. I have a friend that is sold on the Carrier Unit he just purchased. Installed was like $9500 brand new out of the box. I run the TriPac.

Thermo-King will try to sell you THERE inverter which is rated at 1800W. You can buy larger ones including full sine wave inverters inplace of what is offered. Just make sure you size the battery cables accordingly.

I would NOT run a truck without an APU anymore. Especially with all of the emissions crap that's on our trucks now. Idling will screw you up on those systems more than anything else will.

Nor would I install one of these systems on my own. Could I? sure. but there are A/C hoses that are custom made to size. As well as an A/C system that would have to be evacuated and then charged. You might be able to get by with hanging some of the components on the truck, but why only do portions of the job. Plus most of the installers I know either do it all or will likely charge a premium to do a partial job.

My engine is a 2 Cyl Yanmar that drives an alternator and an A/C compressor. Considering I drive a Condo Century, unless it's over 90 or under 0*, I do ok keeping temps. I think that has more to do with lack of adequate insulation more than anything really.
 

mndriver

curmudgeon extraordinare
Supporter
As an addition....

Company I used to drive for has owned the same apu's going on 10 years now. Every time he trades a truck off, he swaps the unit off the old and onto the new.

My personal unit has over 10400 hours on it and shows no signs of wearing out soon.
 

Duck

Quack
Supporter
An APU will probably not benefit a team operation very much unless the truck sits around a lot. And even then, with the little amount of sitting around that teams do, the benefits would not be in fuel savings. At 10 grand, it would take a lot of sitting around with the APU running to pay for the unit in fuel savings. The benefits to a team truck would simply be in keeping maintenance & down-time costs down on the truck's extremely unreliable emissions system. Fuel doesn't burn completely enough at idle, so it puts more "global warming" in the exhaust, which causes even more problems then those systems have already.

And @SkateBoard is wrong about there being no need to keep the big engine warm as long as your batteries are good. He runs a pre-emissions Detroit 60 engine & never plans to replace it with anything newer, so he has no reason to really educate himself much on the emissions systems or even think about them much.

Cold engines are even worse at not burning the fuel completely, especially when it's a diesel that relies on heat to ignite the fuel instead of a spark. In winter, you're going to be blowing unburnt fuel into the emissions garbage whether you idle it or not, because if you don't idle it, you're going to be blowing that crap into the exhaust when you fire it up in the morning, until the engine warms up.

Keeping the oil warm is good for any engine, but if you can keep the upper cylinders warm too it's the way to go with these modern engines as far as the emissions systems are concerned. And the best way to keep the upper cylinders warm would be to circulate hot coolant through it.

I think Skateboard's got the best APU setup in this case. He doesn't have his cooling systems tied together but he's got both an AC generator and a 60 amp 12 volt alternator. Using it's alternator he can maintain his truck batteries but if he needs lots of power to run several block heaters all at once, or run a big 200 amp booster to quick-charge the truck batteries in an emergency, he's got the power available. And he can run an electric block heater too, he just doesn't want to because he had some back luck with one.
 

8978

** Commie Express **
Supporter
Stopped into to Kenworth in Williston, ND to get an airbag. Service manager was at the parts counter. @Duck, he said he wants to know what planet your from. They don't idle, block heat or anything and there is nothing in the manual about keeping the engine warm at any temp. He said about the only thing a company will do is have someone go around and start all the trucks an hour before they head out to get the inside warm and make it easier to shift.
 

Tazz

Infidel
As an addition....

Company I used to drive for has owned the same apu's going on 10 years now. Every time he trades a truck off, he swaps the unit off the old and onto the new.

My personal unit has over 10400 hours on it and shows no signs of wearing out soon.
I know Big G runs theirs for 30k hours. Three different trucks and then they sell them as "slightly used".
 

Duck

Quack
Supporter
Stopped into to Kenworth in Williston, ND to get an airbag. Service manager was at the parts counter. @Duck, he said he wants to know what planet your from. They don't idle, block heat or anything and there is nothing in the manual about keeping the engine warm at any temp. He said about the only thing a company will do is have someone go around and start all the trucks an hour before they head out to get the inside warm and make it easier to shift.
That service manager is an idiot then. Probably just a parts changer. No ability to think outside of what his code reader tells him. It's common sense once you understand that cold engines don't burn the fuel completely & unburnt fuel plugs up the DPF during warmup.
 

Copperhead

Well-Known Member
Cold engines are even worse at not burning the fuel completely, especially when it's a diesel that relies on heat to ignite the fuel instead of a spark. In winter, you're going to be blowing unburnt fuel into the emissions garbage whether you idle it or not, because if you don't idle it, you're going to be blowing that crap into the exhaust when you fire it up in the morning, until the engine warms up.

Keeping the oil warm is good for any engine, but if you can keep the upper cylinders warm too it's the way to go with these modern engines as far as the emissions systems are concerned. And the best way to keep the upper cylinders warm would be to circulate hot coolant through it.
There are far cheaper alternatives, and better, that can solve those issues than using a full blown APU as some do. There are diesel fired coolant heaters just like those under bunk sleeper heaters that can have a completely cooled engine up to 150F in about an hour. Set the timer to kick on about an hour before a break ends. And there are oil pan heaters that use little power, but can have oil warmed to 100F very easily. Now all of that, along with a very good portable generator would be less than $3000, tops. I do this and my Xantrex inverter is also a battery charger version. My Yamaha EF2000is generator can run almost 10 hrs on a gallon of gas and run all of this. The coolant heater runs off batteries like the bunk heater. The oil pan heater is AC but only uses about 500w. I just start the generator before going to bed and hook it up, via a common receptacle, to the inverter/charger and the oil pan heater. It just purrs along at a lower decibel level than most APU's and keeps everything running great. The generator is in a custom made vented box that is mounted on a frame rail. Nice and secure from theft.

Nice thing is, I can also pull out the generator and use it for remote power when I am using some electric devices around my property. Works great for a 18" 4.5 hp electric chain saw I use along with some other items. Generator only weighs in at about 50 lb with fuel.
 
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krelithous

Well-Known Member
Supporter
There are far cheaper alternatives, and better, that can solve those issues than using a full blown APU as some do. There are diesel fired coolant heaters just like those under bunk sleeper heaters that can have a completely cooled engine up to 150F in about an hour. Set the timer to kick on about an hour before a break ends. And there are oil pan heaters that use little power, but can have oil warmed to 100F very easily. Now all of that, along with a very good portable generator would be less than $3000, tops. I do this and my Xantrex inverter is also a battery charger version. My Yamaha EF2000is generator can run almost 10 hrs on a gallon of gas and run all of this. The coolant heater runs off batteries like the bunk heater. The oil pan heater is AC but only uses about 500w. I just start the generator before going to bed and hook it up, via a common receptacle, to the inverter/charger and the oil pan heater. It just purrs along at a lower decibel level than most APU's and keeps everything running great. The generator is in a custom made vented box that is mounted on a frame rail. Nice and secure from theft.

Nice thing is, I can also pull out the generator and use it for remote power when I am using some electric devices around my property. Works great for a 18" 4.5 hp electric chain saw I use along with some other items. Generator only weighs in at about 50 lb with fuel.
I can't see forking out 10 - 20k for an apu again when a decent genset would do the job just fine. and like you said also in a custom made box for theft and so you can run it in bad weather as well. I have a Honda EU7000 and I paired it up with a room AC unit and I still came out cheaper than buying an APU and I can run the microwave fridge coffee pot and ac all at the same time with out having to unplug and re plug crap back in that shits for the birds
 

DubbleD

Color Commentator
I can't see forking out 10 - 20k for an apu again when a decent genset would do the job just fine. and like you said also in a custom made box for theft and so you can run it in bad weather as well. I have a Honda EU7000 and I paired it up with a room AC unit and I still came out cheaper than buying an APU and I can run the microwave fridge coffee pot and ac all at the same time with out having to unplug and re plug crap back in that ****s for the birds
Pictures please!

Unless you licensed it... In which case.... Pictures please!
 

krelithous

Well-Known Member
Supporter
Most of the time, cost/benefit calculations are done on the assumption the truck idles every minute it's not moving. I don't idle enough to justify the cost.
theres some that idle when they don't need to idle when it's not to hot or cold out there sitting there idling there asses off:stare1:. i'm in and out I don't idle my wallet gets tight when I think of spending money. I wonder what those drivers would do if they were in an rv park and they can't idle between certain hours :confused-96::D
 

DubbleD

Color Commentator
theres some that idle when they don't need to idle when it's not to hot or cold out there sitting there idling there asses off:stare1:. i'm in and out I don't idle my wallet gets tight when I think of spending money
I suck at meditation.

I got my tv going, microwave just finished cooking some Act II popcorn, cb is on, GPS, fridge, lights, charging my phone and puter....

Try that without something other than battery power and a clip-on inverter.
 

krelithous

Well-Known Member
Supporter
I suck at meditation.

I got my tv going, microwave just finished cooking some Act II popcorn, cb is on, GPS, fridge, lights, charging my phone and puter....

Try that without something other than battery power and a clip-on inverter.
agree though if I really needed the gps and cb I could run out and buy a 120volt to 12 volt converter box :D. but why in the hell would you want to hear the trash on the cb while resting I know entertainment:D
 

DubbleD

Color Commentator
The Stryker 955 HP monitors voltage as well as hosting my favorite voice....

Contrary to popular belief...I do pay close attention to the needs of my ride.

For the OP....

I have a couple trucks with TriPac apu's.

Far and away, my largest expense is the EPA junk ..... But running second is top brand alternative power units.

I hate wasting money but I'm pretty confident in the newer alternatives that have been mentioned above.

My next retrofit will be a 6500 watt diesel powered generator along with a 10,000 btu AC unit mounted on the back wall like @SkateBoard did along with other key components.
 

DubbleD

Color Commentator
since being mainly local I don't have no use for the genset now :cool: . nor do I have a microwave in my truck either I am home in my bed every night :)
I did local for 3 years...

694/494...694/494 ... 694/494 over, and over .... Always counterclockwise.

I'm now unwound!
 
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