Increased Milage/APU Idea

Heres my opinion. I think you would lose a lot of efficiency by removing the engine compressor, and I dont think you want to remove your engine fan either.

I would look into changing the engine fan to a lesser blade one, (theres a recent thread about a guy switching from a 12 to a 8 blade and saving a lot of power but not sacrificing cooling)

Second going from mech to elec back to mech is extremely inefficent, I would look into a home a/c unit instead. I have seen trucks that cut a hole in the back wall of the sleeper and mount it that way. Not a bad Idea but I think you make a more discreet version. I think use all the guts minus the ac motor and swap it out for a dc motor. I havent seen the inside of a home ac unit in a whie but I believe it can be taken apart and made to fit in a side box. just have to figure out an outside vent for the condensor.

One more alternative is look into hotrod a/c units, you can make a APU unit for way less than a $1000. gas 6hp ohv engine about $2-300, high ouput alt minimum of 100-120 amps and a a/c compressor from either the hotrod kit or figure out a way to elec clutch the home a/c compressor.

If you found a water cooled diesel motor then you can just plumb it into the bunk heater core for its cooling system, run it in series where it goes from main system-apu-bunk heater core-main system. that way in winter you can still hopefully keep some heat in the main engine, or route the coolant line from the apu engine to the bunk to the fuel tank (if they still have that water line that runs through them) to keep it from gelling. obivously in spring thru fall you reroute to the main engine cooling system to keep the fuel cooler.

Your going to want marine batteries or those big monster fleet farm ones that busses and farm implements use. You want reserve capacity not cranking amps.

Im sure ill think of more or revise it after I think more into it.

 

Another idea for charging would be some sort of solar panel on top of the cab as well as tied into the factory charging system. All you would need is a battery isolator between the factory system and the new batteries. I have been doing a lot of research on home solar setups and it's amazing how much power you can get from one. You can pick up used panels on ebay for pretty cheap too. And yes, your blower motor and all accessories are 12 volt.

 

Solar prob wouldnt help you any if you run during the day and sleep at night. plus the panels you get at harbor frieght only put out 55 watts a pieces for a 2'x4' panel plus there like $400 a piece.

Back to engine fans, I think adding a set of dual fans say from a taurus or aftermarket would be a good improvvement if you had the switchs and relays to control both the mech fans and elec fans. I would mount the fans directly behind the intercooler so that the air charge is as cool as possible thats being fed to the engine, cooler charge air keeps the engine cooler so its a double give me for cooling and more power.
For example If I had my own truck Id instantly look for a lesser blade fan /shallower blade pitch or modify the existing one by removing a couple blades then rebalancing it. Then have a setup or relays/ temp senders. nothing to complex just enough where its pretty much automatic to do what i want it to do. For example if i was in the mountains i would want my mech fan on anytime i am coasting down hill and the engine temp is anything above what the thermostat temp is so its as cool as possible for the next hill. Along with that I would have an adjustable temp sender set for 2-5 degs above thermostat setting hooked up to a relay so it will kick in the elec fans basically right away when you start climbing (an elec fan doesnt draw hardly any power from the engine via the alternator) the other reason to kick the fans on as early as possible is to prolong the heat soak of the intercooler. Im basically just trying to prolong the mech fan from kicking in as long as possible to save MPG and all the power to get over the hill.

The other thing is a puller fan is ALWAY better than a pusher. however someimes theres just no room for pullers so you use a pusher. Reason being pullers are better is that with a puller normally its mounted more then a inch away from the rad core and has a shroud box that pulls air through the entire core inside the shroud. with a pusher however they are normally mounted tight up against the core causing a hot spot in the core where the fan motor is and no airflow can flow through it. Im sure you guys know this but most fans can only be ran in the driection they were made from factory if its a puller must be ran as a puller, only very specific fans are uni direction pusher/puller types. You can tell by the look of the blades/pitch whether its uni directional or not.

 

the one thing about trying to use existing equipment its difficult to tie into it and make it work even half as good as oem. But adding a separate system I think would be easier to workk into the truck and look semi professional, and probably cheapier. I think the hot rod a/c is the way to go with a small engine and a dc alternator.

The next section is just scattered ideas that are running thru my head at the moment so there not organized.

If I had my own truck heres what Id want in it
a dorm fridge, min of 1000 watts for a microwave/ laptop charger/ tv

Having a small engine with a alt to keep the batteries topped off. One more thing with the small engine (if its air cooled) I would make an exhaust manifold that has water running through it/around it and into the trucks cooling system. So you will have heat in the bunk heater core along with hopefully in the engine.

I would like some peoples input on there experiences with a generator vs using a 1000+ watt inverter.

Which one do you feel is better as far as RF interference, battery time vs fuel usage and and limitations to both as far noise vs having charged batteries.

I guess my biggest question is what combination would be better and what would you choose, Ill throw out some price ranges just so you have an idea

1. ac generator that you have to run anytime you need ac power with no dc charging (possible to incorporate a dc alt into the system though) 3-4000 watts $4-600 for gas, unknown for what a diesel gen costs.

2. A small engine with DC alt, and a big inverter, and air conditioner either engine ran or inverter ran. $3-400 for gas eng, $250 for home a/c unit and alt, or $800 for hot rod unit. $300 for brackets, cable and 1500-3000 watt inverter, 2-4 reserve batteries $1-300

3. AC generator with dc alt and a med inverter for small loads without having to constantly run the engine. $500 for gen, 150 for alt/brackets, $100 for 1k inverter

4 the most costly of all everything a apu has. generator, A/C, dc alt, water cooled (main engine heated and bunk heater) engine $5-700 for gas $1000 for diesel, hot rod a/c $800-1000, alt $150, $200+ for wiring and plumbing. Im sure im missing something but these are just brainstorms

 

6500watt Diesel gen set $1600, 12000 btu heat pump $599, circuit breaker box apx $50, wire $30. Gen set needs ultra LS disel and has remote starter. Heat pump is single hose stand alone system. OR use Mini split heat pump system 21 EER, 18,000btu $1799.

The breaker box is ony for additional safety and to split 220, less wiring. Gen set use .3 gph. runs about 12 hours on 3.3 gallons at load.

 

There is already a system that does everything you are asking for. Google "Sun Power Tech" they have a battery based APU system with 12 volt AC system. They recomment a 200 amp alternator.

I have looked at a 3 cylinder deisel engine to run an ac compressor and a large alternator before too and by the time you put all the parts needed together, you might as well by the complete system.