Wondering about a great new energy-saving deviceyou found on the Internet? Jeff no longer answers questions online.This will remain as a searchableresource for all BHM website visitors. Air conditioning for a pickup camper Thursday, November 27th, 2008 I would like to put Air conditioning in my pickup truck camper shell to keep my dogs cool in the summer. It would only be in use when I was traveling down the road, not while the truck was turned off. Here was what I was thinking – could you offer an opinion on whether it would work or how to to do it, if it is even possible. [I want to] put an RV air conditioning unit on the top of my camper shell and run that off an inverter connected to my pickups battery. I do have a 2500/5000 watt inverter but I wonder if the air conditioning unit would suck so much energy that the alternator could not keep the truck battery charged up going down the road.. My truck has two batteries up front The problem is not battery size, it’s your alternator capacity.

There is no way an RV air conditioner can run off one or two truck batteries for more than a few minutes without draining them. For example, the smallest, newest, and most efficient truck camper AC unit draws 8 amps at 120 VAC. Assuming a 90% system efficiency, this would be a 1,100 watt “run” load on your inverter, and require an inverter that can handle at least 2 kW “start” load since any compressor load is a dead short on the power source for the first few seconds it is trying to rotate. You said you had a 2,500 watt inverter which should be able to handle a small RV air conditioner, but that is not your main problem. Your inverter will have a constant draw of 88 amps at 12 volts DC while an 8 amp load air conditioner is running, and could draw up to 150 amps for a few seconds every time the compressor kicks in. This means your truck alternator and all related cables need to be large enough to handle these larger current flows and still have enough excess power to operate your lights and other electrical loads in the truck.

Each time you stop at a light, there will not be enough amps coming from your alternator even if it is a larger 150 to 170 amp heavy duty model. This is why the air conditioning unit in an RV is always wired into the exterior shore power or generator panel, and not powered from the batteries. Any 120 VAC electrical load on an inverter will draw 11 times the AC amps from a 12 volt DC battery.car ac repair savannah ga I suggest letting the dogs ride in the back seat!sterling auto repair tampa fl This entry was postedportable ac unit 9000 btu on Thursday, November 27th, 2008 at 5:31 am and is filed under Air conditioning, Alternator, Camper, Car/Truck battery, Truck, Vehicles. You can follow any responses to this entry through the RSS 2.0 feed.

Both comments and pings are currently closed.This little rig was home built from a salvaged fiberglass pickup topper because my wife and I did not care for what was commercially available.  When we built the rig we didn’t want a major investment in a larger outfit since we could not travel enough to justify the expense. The Chevrolet Silverado truck that we are now using replaced two older, high mileage vehicles; it was selected for its passenger comfort, cargo capacity, and towing capability.  A special intended use for this truck was to haul a camper, or tow a small camping trailer. During the process of selecting a camper or trailer we came to a conclusion; we didn’t want to use a trailer, and the campers that would fit our truck were very heavy and full of features that we didn’t need or want.  What we needed was a small, practical unit that weighed about 700 pounds, which is about one-half the weight of the commercially available units.  We only wanted a place to sleep, a couch that allowed us to lounge a bit, an ice chest, a sink with limited water supply, light cooking facilities and a toilet.   

The only luxury would be the installation of an electrical system, which would allow us to have an air conditioner and electric heat. We decided that we could build a slide-in camper of our own. An older eight-foot fiberglass topper was found in a local salvage yard for $50, and for an extra $5 a stainless steel sink was harvested from a salvaged motor home.  The sliding windows in the topper only required cleaning and replacement of the screens. Because we had a 6 foot bed, we measured out what our finished roof height would be, and cut a notch out of the front of the 8 foot topper, which allowed us to put about two feet of the topper over the top of the truck cab as a storage area that is accessible from the inside.  To give added headroom in the camper a six-inch high box beam was built between the bottom of the topper and the rails in the truck box. An exterior cargo container was made from furnace ducting and attached to the front of the camper.  These details can be seen in the picture at the top of the article, taken at the Arches National Park.

All construction is either the original fiberglass topper or 3/8-inch to 1/2- inch plywood.  All joints are done with close grain hardwood blocks, high-grade wood screws (stay away from drywall screws) and either Epoxy or Polyurethane glue. All of the construction can be accomplished with common hand tools. Power tools needed, at a minimum are: saber saw, drill, and sander.  Access to a Dremel power tool and hand held belt sander would be helpful. Finished dry weight of the unit is 440 pounds, which is less than 1/3 of the rated cargo capacity for the truck bed, and 700 pounds less than the lightest factory built unit.  Handling has not changed to any degree; there is no wallowing, swaying, or noticeable instability when carrying the camper. Loading is easily accomplished with two lifters made out of boat trailer winches, which were fabricated by a local welding shop. Total cost of the cRamper was about $1.25 per pound.  In five years of use it has paid for itself.  We have spent many nights for no cost, and have found the average cost to be less than $25 per night when using commercial RV parks.

Layout of the unit is conventional for the couch, which is about five feet long, being oriented from front to rear; a fold down extension extends this to a full six feet long.  Since there is limited headroom, the top bunk is oriented across the unit, and elevated about two feet above the bottom bunk.  The result is that the occupant of the bottom bunk has feet and lower legs beneath the top bunk.  The picture shows the unit set up with the top bunk in place, but lacking the mattresses, which were in winter storage when the picture was taken.  Mattresses are base camp type foam and air products, which are available from most outdoor stores, or found on the Internet. For a toilet we chose a Fiamma, which is very similar to the Thetford brand and others, which can be purchased at most stores that have a selection of camping goods, or through a well-stocked RV dealer.  Ours is placed on a securely mounted stand, and held down during travel with a heavy cargo strap The main part in the water system is the $5 sink, which is mounted in a counter and cabinet arrangement just forward of the toilet. 

Water is pressure fed from a new, unused three-gallon yard sprayer, which is mounted near the ice chest, and plumbed into the sink with a longer hose. Grey water is collected into a 2-1/2 gallon lawn mower fuel container located near the back wall.  The interior pictures do not feature the water tank since it is in winter storage. We use one of the newer ice chests, the more heavily insulated type, which is securely strapped down while traveling.  Depending on the weather, a 10-pound block of ice and some cube ice will last at least two days, and up to five days. Air conditioning is with a common residential 110 Volt window unit mounted through the back wall, and if the temperature drops, a portable ceramic element bathroom heater keeps us quite warm. The unit is wired with automotive multi-strand wire rather than the single conductor residential wire, for flexibility and vibration resistance.  There are three wall sockets in the unit to power the air conditioner, electric heater, laptop computer, and various battery chargers.

Lighting is by small wall mounted 110 Volt AC, and 12 Volt DC florescent lights.  These smaller light fixtures can be found in hardware and RV stores. Our “entertainment center” is a $20 portable AM/FM radio. While camping we prefer to keep the preparation of meals as simple as possible.  If we are camped out in a national or state park that has no electrical hookups and decide to prepare a meal, it is done with a one-burner back packing stove.  Eating out is done quite often while traveling because of the unique dining experiences available while on the road. We do not “live” in the cRamper, it is what gets us to where we want go, to “do things.”  The type of travel and camping that we do generally has us moving location every several days. Many of our zero cost overnight stays have to do with stopping on the way to a destination, and needing only to stop and sleep.  A considerable part of our travel is on the old main highways that have been superseded by the Interstate system.

Traffic is much lighter on the old main roads, which is a pleasant change from the pressure of driving “the slab.”  Many of the area attractions are located along the older main roads anyway, and opportunities for low cost camping are plentiful. There are local restaurants in the off-Interstate areas that are worth taking the time to find. Fuel consumption of our truck remains in the 16 – 19 MPG range.  Cruising speed is selected to blend with the existing traffic flow, and has been as high as 85 MPH.  We can park anyplace standard automobiles can, except in the older multi-level parking garages, since the top of the camper is at 7’ 3”. Our travels with the cRamper have taken us “from sea to shining sea,” the Gulf Coast, Great Lakes, the Banff-Jasper area in British Columbia, and places in between.  Metropolitan driving has included Chicago and New York City. We will use our cRamper for another two or three years and then plan to convert a commercial van into a unit that has more homelike amenities and more interior space.  

There are no plans available for the “cRamper.”  We did some measuring and figuring and then just built it.  Most of the items used to put the unit together can be found in large full-service hardware stores or through RV dealers.   Information on how to use the items and materials is available from the retailer, or on the manufacturer’s website.  “Shopping “ in auto wrecking and general salvage yards is highly recommended. While there are not a lot of details on how to replicate what these folks have done, there really can’t be. Your pickup bed may be a different width and length, and your shell will certainly be different. However, they have several ingenious ideas we can all benefit from: 1) Take what you have, and can afford, and make it work. The cRamper works much better for them than campers weighing and costing 10 or 20 times as much. 2) Pickup shells can be found very easily and modified to gain the extra height needed. This is a huge advantage over living/traveling in a van, which are very difficult to raise.