RV Ideas to consider ???

[FrankR]

Inverter mounted in bed of puller truck.. Separate power cord to trailer from inverter. Great for quickie lunch breaks. Electric power always available.
Using timer connected to converter to keep batteries charged. Some trial and testing needed. Usually about 2 hours a day will keep voltage at 12.6..
Rigging auto alarm remote to make ICC/clearance lites come on.
Install new phone lines with wall phone.
Provide cable for DSS or cable from shore connection.
Install central thermostat to operate exhaust fans when temps rise to chosen temperature.
Install small lite with switch at front center near hitch coupling for connect or disconnect.
Install small fan at rear of refrigerator[help exhaust heat upwards] manual switch controlled with ac or dc power
Just thinking??.Frank

[hex]

Frank R. wrote:

Inverter mounted in bed of puller truck.. Separate power cord to trailer from inverter. Great for quickie lunch breaks. Electric power always available.

Frank I thought I read that your inverter was in the bed of your dually.
Since electric power is always available in trailer (Battery), are you talking about running Air-conditioner and perhaps Microwave during lunch break? If so how big an inverter would be necessary and would you need to leave the truck running? If you did not leave the truck running what would be the effect on the truck battery? Say you dozed off after 45 min. lunch for say 60 more minutes?

Where would you plug in the inverter?(you said separate cord)
Is this a feasable way to leave the Air-conditioner and perhaps a 110 Refer running while underway on the road?

BTW I have been hoping you would weigh in on my Safety/Lightning question somewhere in the Community/Gen.Discussion section. I enjoy and look forward to your posts.

thanks,

[74Argosy24MH]

Air conditioning is basically impractical to run off an inverter. The real problem is the battery drain. Any current on the AC side is 10x greater on the DC side (plus any loss in the inverter). My air conditioner draws 13.5 amps, it would draw more than 135 out of the batteries. Unless you have an aftermarket high output alternator it would kill the battery in a very few minutes.

You could probably run the microwave for reheating leftovers, but again they are a heavy draw (usually somewhere around 1500 watts for a 1000w unit, or 12.5 amps). I would leave the truck running and make sure the battery had time to fully recharge. Nothing worse than getting up from lunch to a dead battery.


John

[hex]

Great idea about "capping" that male plug!
Now how do you get the extension into the TT to plug into the 120v wall outlet?
And is there any problem in the backfeeding of 120 thru the system?i.e. what happens at the trailers breaker box? Would an overload still trip the trailer breakers? (I am assuming that there are some less than 30Amp breakers in there)

Can a generator in the truck bed be backfed into the 120 system the same way (wall outlet)?

How big is your inverter? Physically? About what is its weight? What are the best brands?

You say it is monitored and controlled from cab. What attention does it need while in use?

Lastly for now: Can I assume that there is no easy or good way to operate the Air-conditioner while underway on the road.

[hex]

Frank I have gone back and edited out my refernces to 110v changed them to 120v.
Hope this makes you feel better.

Each electrical system must be tested and researched. Basic electrical knowledge is required. Did I mention a wind generator and solar panels??

Could you be annoyed one more time long enough to reccomend another Airstream site where those of us with less than your idea of "Basic electrical knowledge" might be welcomed?

Nonetheless:...Thanks anyway for your trouble.

[FrankR]

I shall not offer more info..... Ya got me..

[davidz71]

A friend of mine in East TN. is looking at a wind driven generator to power his house along with solar. Last year he did all the research and was planning on tackling this sometime soon. I will email him to see what he has accomplished.

[74Argosy24MH]

Frank-

You mentioned something I have been considering for some time, adding a fan to the cool the refrigerator coils. I am going to use a little knocked up thermistor-transistor circuit to control it, but have thought a lot about placement of the fan. I go back and forth between beneath the coils and at the top beneath the cap. Any thoughts?

How's your AC installation coming?

John

[Pahaska]

Doesn't seem to matter a whole lot. I have had fans both places and they worked equally well for me.

If you consider that the refrigerator is designed to operate with just the airflow caused by thermal currents, it is pretty obvious that you don't need to have a whole lot of airflow. The solar fans that CW sells seem to work as well as anything I have seen.

Personally, I have always used surplus 12v computer fans at a couple of bucks each. Two small fans in series or one fan with a dropping resistor makes them super quiet and reduces the battery drain.

[74Argosy24MH]

Maybe that is why I can't decide, it won't make that much difference. I can think of pros and cons for each, but like you say anywhere beats convection. I have a couple of 3" muffin fans I was going to use, so I guess I will stick them where there is room (anywhere but behind the door).

Thanks
John

[uwe]

They ( online RV Fridge dalers) say that sucking out the hot air with fans near the top of the chute is more efficient and less prone to disturbing the flame?? It sorta makes sense.
One thing deas absolutely make sense - creating a narrow spot near the cooling fins for air to rush by. I looked behind my fridge and there is a large area behind there, probably 6 or more inches or airspace. One should make a baffle that directs the air over the fins, instead of ignoring the fins and rushing past aimlessly.
This alone should already increase cooling efficiency enough, the added fans being a safety margin. The distance should be 1" or so. Basically like a firebreak in a stud wall, but sticking out to almost reach the cooling fins on the rear of the fridge.
I have yet to install my fans, don't want to get into a project while it's still nice out. Ahh, Winter is just around the corner.

[74Argosy24MH]

Disturbing the flame was one of my concerns with a low mounted fan, but blowing the air directly on the coils seemed more efficient. I like the idea of a venturi over the coils, the fan could be at the top, the bottom can be open with no flame problems.

John

[uwe]

Thanks,, John. Venturi was the word I was looking for but could not remember in the previous post.

[74Argosy24MH]

Thanks for the idea, I hadn't considered that. I could see pro and con for high and low mount, but yours seems like the best.

John

[hex]

Hey guys is the reason for doing this primarily to enhance the cooling efficiency of the refer?

Or to lower the ambient temperature in the coach?

Is there actually a draft of warm air coming out around the refer or through a wall or spreading along a wall or what?

[74Argosy24MH]

Primarily to make the refrigerator more efficient. Cooling on these is by convection and they work well as long as there is a large temperature differential. As soon as it gets hot you have the dual problem of not getting the air flow over the coils and the refrigerator needing to cool more to make up for the air temp. They don't have all the fans internally and externally that move air like a home refrigerator and don't compress a gas which is more efficient for cooling to start.

All of the area around the refrigerator should be sealed from the inside of the trailer. Anytime you have a flame (furnace, water heater, refrig.) it should have an outside air inlet and exhaust to prevent carbon monoxide from entering.
John

[davidz71]

So if I mount a minibox fan, say 4 1/2" dia., above the coils and pointing upward to pull air toward the vent then it will be more efficient?

[74Argosy24MH]

Much more efficient. I had a pickup camper and thought the refrigerator was dying. I put a fan about the middle of the coils (as high as I could reach to work on it from outside) with a switch for on-off. I would turn it on around noon and off in the evening. It made it an actual refrigerator again.

John

[53flyingcloud]

For the last two seasons, I've ran a small floor fan in there tilted/pointed upward with no problems..Best of all, it really kewl its off..Plug'd in the ac outlet and it has it's own sw. KISS...know what I mean? total cost of fan, less than 10$
ciao