Best APU To Buy That Does It All ?

Depends on the truck, for flat top sleepers I wouldn't want less than 7500btu, for mid roof and condo sleepers nothing less than 10,000btu. Personally this is one of those things where bigger is better, there is nothing worse than sitting around let alone trying to sleep when you aren't quite cool enough to be comfortable.

 

Mine's 7000 Btu's and 100+ degrees outside it might get the top bunk down to 89 degrees. With a big fan at the foot of my bed I can survive that but my dog really suffers downstairs so have to idle the truck during the really hot days.

Something I am interested in is the Cabcool Backwall air conditioner seen on truckcomfort.com. Just not sure a honda 2000 could power it.

 

A/C and heat units are misleading when it comes to truck APU's. I have a Rigmaster and the A/C just wasn't doing it. I tried a portable A/C stand up unit which was useless. I put a 15,000btu unit on the roof of my truck. Also useless.

I was pretty much how can this be. I have a 12,000 btu at home and it will freeze me out of my condo. I also noticed the airflow coming out of my home AC was a lot stronger then the ones in my truck so I started to dig.

When I looked at the specs for my home AC unit it said something like 900cfm. That's the airflow coming out the vent. When I looked at the specs for my Rigmaster and roof top AC unit it said something like 600cfm BUT.....with an * next to it. At the bottom it was air flow before the condenser. Now it made sense. By the time I figured it out they all put around 278cfm out the vent! Plus! The condenser is only about 1/4 the size of a home AC unit.

So, your comparing apples to oranges.

I ended up doing this..It's a 15,100 btu AC unit.









Here is a test I did in Las Vegas in the summer. It was the first real hot day I could test. I pulled in and shut the truck off with the windows up. I went inside and took a shower and ate. When I came back out it was 150 inside the truck. I fired up my APU and the AC unit. At the end of one hour it was 67 inside and the fan stayed on low the whole time. It was also cycling on and off to maintain 67 instead of going lower. This is also with the cab curtains open so it was cooling the front of the cab. This temp was taken from the drivers seat. I did have curtains up in the windows though.





This unit is too big for my truck and if I were to do it again I would put a 10,000 btu in.

I have a few tips. I have a Rigmaster with a 6kw generator this AC is nothing for it to run. If you go with a Honda 2,000 you could possibly power a large unit like this but you need to read the specs on the AC unit. It must be a slow start unit. They did this because many old house are still on 75 and 100 amp service and blow the fuses when the AC compressor starts up. The compressor only surges when it starts. A slow start unit has a giant capacitor in it. For those that don't know, a capacitor can be used as a large battery used to take the surge.

Many rental places rent the Honda generators. I would suggest doing a test. Rent the generator then buy an AC at Home Depot and run it for a few hours. If it doesn't do it bring the AC back for a different size.

 

A Honda EU2000i would struggle. I have one. You can even borrow it if you want to try one. I also purchased an 11k btu portable a/c unit, opened it up, and installed a start capacitor. If you try to run the gen in eco mode to save fuel, it will trip the breaker on the a/c unit when it attempts to start the compressor. Switch eco off and it will run ok. The a/c unit is rated at 11.8A max, and it momentarily overloads the gen when the compressor starts, even with a capacitor to kick it. In eco mode, the gen isn't spinning fast enough to carry that overload and the voltage drop causes a current overload that trips the breaker. When running, the a/c would keep a FL Century with a condo bunk comfortable. Had we taken the time to rig up a better exhaust solution for the a/c unit (a sealed duct instead of just putting the hose out a window and covering the gap with cardboard), it would have been even better.

Add to that, with the a/c running you're already working that 2kW gen hard, so forget about running much else other than a cell phone or laptop charger. Just enough left for maybe a TV, but definitely not a coffee maker or microwave. You'd have to shut the a/c off to use those. On the plus side, walking your gas can to the car pumps will be heart healthy. Unless that's where you parked LOL.

 

My little honda 2000 does OK with the 7000 Btu portable. What I do have to do though is run the generator on full throttle for about 20 minutes or so so that the A/C begins blowing cool air. After that it can be put on low idle Eco mode for the duration.

Have to get up about every 5 hours to walk the dog so will top off the gas and it will get us through the full 10 hour break. Been a few times though the thing ran right out of gas and had to get up and turn on the truck to cool things down and start over with gassing up the gen and 'priming' the A/C for the 20 minutes on high idle.

2 gallon gas can and 1 gallon capacity generator represents about 20 hours run time. So on about an every other day schedule to get gasoline for it. If I wanted to stay at a rest area, I have to think about how much gasoline do I have onboard lol. Sometimes just whip into the PFJ and top off the gas can, using the rewards card gets a $0.99 coffee as a bonus.

The generator rides on the passenger seat floor, so never put gas in within 2 hours of putting it away or will have to run with the windows down til the gasoline vapors from the freshly closed cap vent evaporate.

This thing was a real lifesaver, many times while at Swift customers they would take my keys so at least we had A/C while being unloaded. I recall the one forklift guy's response to another Swifty when he protested about the temperature and not being able to idle for comfort-- "I don't care..."

 

APU's are good, the diesel powered ones like Thermoking, Carrier, and Dynasys. There's others, the battery powered ones have not heard such good reviews, mixed reviews on other options. But yah, they're like $10,000. So some of us get gasoline generators and 110 AC's and quartz heaters instead to save money. The Honda gen's run quieter and cheaper than an APU. you just have to walk over and fill your cans.

for heating the diesel fired heaters, aka Espar and Webasto are awesome, sometimes you have to clean the screens and glo stick. but they will roast you out of there and are dead quiet, don't drain battery. perfect. But sometimes if you already have a gen. Maybe you run it to power your laptop or a microwave or something, well, it's just easier to plug in a quartz heater, they work fine too.

 

My espar heater broke down a couple winters ago-- basically the screen got fouled. At the time I didn't know anything about servicing it. Learned that to replace the screen would have to pull out the glow pin. To pull the pin would have to spend $225 for a new glow pin which comes with the tool so we could replace the $10 dollar screen.

Had to take the bottom bunk bed apart to access. Worked on the thing for 2 days couldn't get the screen out so put everything back together. Some time later found some tool tweezers which should reach down into that hole and get the screen out but haven't had the desire to take the bed apart again so bought a $50 buck heater which works perfect.

 

My espar quit working at the end of winter,. I only had it a few months, purchased at beginning of winter.... I'll clean it out come winter again. Kind of a finicky unit. But awesome when it's working. I just need to get a kerosene bottle to run on occasion to clean it out or run kerosene full time to extend service intervals.

For AC, I'll probably go the home brew route with a gasoline generator and portable ac. I'm usually fine with just two little fans going to keep the air circulating.

Most people talk about return on investment, ROI, with these over priced APUs, but for an owner op, like me, the ROI is much longer. I don't idle much as is. Nor would I idle on a nice day. I'm good from 45 - 65 degrees. Now the espar heater was great, when working, but had I already had a generator, I wouldn't have gotten it. A regular plug in space heater would suffice.

To to add to that though. Once I had my espar I was running it a ton to stay in that comfort zone. More so than I would a generator and space heater. It's a slick unit, that doesn't cost anything noticeable to run once initial purchase, install and service is accounted for.

Now add up all the hot days it's over 65 and all the time I'm just sitting in the truck. It would take me 7 years for that expensive APU to pay itself off, especially adding up the service costs. That's my numbers. And I have to add something against myself. If I did have an expensive APU, I'd use it all the time and love every minute of it. I'm just too cheap and stubborn to fork over $8-10k.