New RVer

Discussion in 'Beginning RVing' started by 3DPiper, Oct 2, 2008.

  1. 3DPiper

    3DPiper New Member

    I just purchased an RV! I'm hoping you guys can help me with some questions..


    1987 American by Cobra Class C
    Ford E-350 Chasis, 60K miles
    Parallax 7355 Converter
    Onan Emerald I Genset
    G6A-7SPK Water Heater
    Thetford Aqua Magic V hand flush toilet
    GE 700W Microwave
    Dometic Americana RM 2652 Refrigerator
    RV Products 8333D876 Series 8000 A/C

    1. I have no RV owners manual. I can't find anything about American by Cobra (although I did find out it is NOT American Coach). I DO have manuals for the converter, toilet, microwave, refrigerator, and A/C.

    2. Help me understand the converter. The generator creates AC that feeds the AC plugs and appliances (A/C, refrig) and the converter. The converter converts the AC to DC for the DC devices (lights?) and charges the generator battery. When the generator is not running, I can still turn on interior lights. Does this come straight from the generator battery?

    3. Can I run the generator while driving (so I can run the A/C)? Unless plugged into a power source, running the generator seems to be the only way to run the A/C. Do I have to worry about overcharging the generator battery (the engine alternator charges the generator battery AND the converter)?

    4. Would it be advantageous to get more stuff that runs off of DC (TV/DVD) and add a couple of extra batteries? Possibly replace all the lightbulbs with LED bulbs?

    5. The one thing that does not work is the fuel gauge (very important!). :(

    Overall I am very happy. It has new tires, all new belts and an engine maintenance check, seems very clean, and drives very smooth.

    The only red flag: my wife noticed today that when we let all the shades down, there is a noticable water stain that is at the same level on all the shades.. Could this have been underwater? Any way to know?

    I still have to figure out all the pumps and ins/outs/hoses for the various waters..


  2. Kirk

    Kirk Senior Member

    Re: New RVer

    1) You will probably not locate an owner's manual since the RV is more than 20 years old and the Cobra company has been out of business for a very long time.

    2) The RV has two different electrical systems, one for 120V shore power and the other is 12V-dc and the prime source for that is the coach battery or batteries. The converter is a device that takes 120V power from any source and converts that to 12V-DC to supply the primary systems and to recharge the battery.

    The on-board generator does use the coach battery as a source for starter power, but it does not supply any 12V power. What it does do is to supply 120V power to the same places that your shore power cord does and one of those is the converter.

    The most vital electrical items in an RV are powered by 12V-dc so that you can use them with no shore power and without the generator operating. Those systems can get power from the coach battery, or from the converter and when the chassis engine is running it too will supply 12V power to supply the appliances and to charge both the chassis battery and also the coach battery. The chassis battery is separated from the coach battery when the chassis engine is not in operation, to prevent it being depleted by the coach loads.

    The coach uses 12V power to operate the control circuit boards of the refrigerator, the water heater, the controls and blower of your furnace, your lights, and the water pump. The reason is to allow you to use everything if you do not have 120V-AC power.

    The refrigerator, water heater and furnace do not work with no 12V power. The refrigerator will not work from 120V power if there is no 12V power because it is required for the control circuits.

    Your air conditioner operates from 120V power only, but if it has thermostat control then it too will require 12V power as well. With and 87 model, you probably do not use the thermostat for the air conditioner and it has a local control on the face of it instead, but you will have to test to make sure.

    3) The on-board generator system is designed to be used when traveling on the road or when sitting still. It is a very common practice for motorhome owners to operate the generator in hot weather to supply extra air conditioning since the dash air is not nearly enough to keep the entire RV cool. There is no problem from your converter harming the coach battery when the chassis engine is charging also as it will just idle since the chassis generator is a much better charging device and only the higher voltage one actually does any work. Nothing to be concerned about there at all as it was designed to be used in that way.

    4) That just depends upon you and how you expect to use the RV. If you usually go where you have shore power, there would be nothing to be gained from this. If you expect to do a lot of camping in places where there is no shore power, then more batteries will be helpful. But keep in mind that the more you try to operate from the batteries, the more batteries you will need and the longer that it will take to recharge them. The best source of charging for your coach batteries is the chassis engine.

    5) I'm not sure what I can tell you on this, other than the fact that this usually requires dropping the gas tank.
  3. C Nash

    C Nash Senior Member

    Re: New RVer

    The stains on the shades are most likely caused by condensation of the windows or just sun fade.
  4. 3DPiper

    3DPiper New Member

    Re: New RVer

    Thank you very much for the info!

    I do know that I have two batteries: one for the engine and one for the generator. The generator battery is a very large deep cycle type.. I assume when nothing is running (generator, engine, shore power) when I turn on lamps I am using the generator battery?

    We did a little back-yard camping last night and I discovered a few more things:

    - there is no garbage can

    - I can't figure out how to let the awning out. Well, I can get it out, but I can't seem to get it to the correct height. You have to duck to go under it and the door scrapes it.

    - The main door is ill-fitting, you have to lift the handle for it to close properly. Is this something I can fix, or do I need to have it serviced by an RV dealership?

    - You can't run the A/C and a vacuum cleaner at the same time ;)

  5. hamdave

    hamdave New Member

    Re: New RVer

    As Kirk explained, but apparently didn't make it perfectly clear, You have a 'coach' battery , NOT a generator battery. The generator uses the 'coach' battery in order to be started, and once it is started the generator supplies 120v ac for your RV and powers all AC loads.
    I don't have a garbage can either that came with my rig. I have a plastic one we keep next to my couch and another in the lavatory.
    Your awning should have an adjustment on each end that extends the rail that holds the awning up. I can't tell you how yours works because you didn't supply any pics, but maybe one of the others can do that for you.
    Can't help you with your door.

    What type generator, and power rating is it? Since your rig is 20+ years old, I'm assuming it could be 20 amp or 30 amp rated. My old class-C didn't have a genny at all.!!It was a 1974 Dodge Utopia (about 23 ft).

  6. 3DPiper

    3DPiper New Member

    Re: New RVer

    Ahh.. Sorry about that, you are correct, I didn't understand that 'coach' meant the second battery.. I get it now.. Re-reading Kirk's post now makes a lot more sense..

    The fellow I bought it from never called it a 'coach battery', he just called it the 'generator battery' which is confusing because then he would say "It's only used to crank the generator"..

    I'll post some pics later today..

  7. Kirk

    Kirk Senior Member

    Re: New RVer

    The way that your awning adjusts depends upon what make you have. The two common ones are from A&E or from Carefree. Either one will have arms on each end which hold the roller tube and that hinge out and away from the RV as you pull the awning down. Both types have a latch on the end of the roller tube at the front of the motorhome which has a lever or arm that you use to sift it from rolling up to unroll it. In both cases, there should be a strap with a loop hanging out of the rolled awning near the center which you hook with a metal rod for the purpose and use that to pull the awning down.

    Once it is down, there will be a second set of arms at each end which hinge from the top near the bracket holding the edge of the fabric and that can be slipped up the arms as they telescope to adjust length. On these smaller arms, there will be some type of latch to allow it to telescope, and once it has been extended into the raised position, tightened again.

    Next, look at the heavy arms that hinge at the bottom and hold the roller tube as they will have some type of latch which you release and the extend these to raise the roll tube making it farther from the ground and increasing the distance to the awning fabric. If it happens to be raining, always leave one arm lower than the other to promote drainage.

    To retract the awning, reverse the process.

    As to the air conditioner and a vacuum cleaner at the same time, did you try that when operating the genset, or were you attempting to do so when connected to a standard outlet from your house? If from the genset it should easily serve both and there is some very serious problem if it does not carry the load. If, as I suspect, you had the shore power cord connected to the house, by using an adapter to make your 30A power cord connect to a standard 15A house circuit, then the reason is quite simply that you are trying to run more than 15A worth of equipment from a 15A outlet. It is a safety device that your house trips a circuit breaker. It is supposed to do that.

    It is never wise to operate the RV air conditioner from a house circuit unless you first verify that the voltage is not falling off as it usually does in such circumstances. If you do that a great deal, you will damage the air conditioner. If the voltage does not fall below the 110V level, they you can do so but the air conditioner requires a run current of 13.5A and so you have only 1.5A left to operate anything else. Since most vacuum cleaners require at least 5A it just don't have enough power and the breaker trips, thus preventing the over heating of your wires which could cause a fire in your RV or in your house.

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