Mis-Wired Motorhome Electrical Connection

I attempted to create a 30-amp plug off of my house for my grandmother's National motorhome. I did not do a good job of explaining to my electrician and he hooked up a 240-volt connection instead of a 120-volt connection. When I plugged the motorhome in we heard popping noises and then there was smoke. What should I expect to have burned up?
Steve, (Jacksonville, NC)

Steve, I’m so sorry to hear about that miswiring. Unfortunately, many items onboard the motorhome could be affected. Virtually all the120-volt AC devices need to be carefully checked; refrigerator, microwave, converter, air conditioner, inverter, television, circuit breakers, GFCI, receptacles, switching devices, etc. Most assuredly some components may have been harmed, but it takes special troubleshooting procedures to fully evaluate the situation. Do not energize the coach from any AC source until the unit can be thoroughly tested. 


In addition to the individual components, the wiring itself should be hi-pot tested to reveal any damage to the insulation on any circuit. All of these tests should be performed by a competent, well equipped RV shop employing certified RV technicians. 

It’s unfortunate, but you’d be surprised how often this actually happens. The first rule before plugging into any new power pedestal or receptacle is to measure the voltage and check for the proper polarity. I say this, not to rub salt into your wound, but as a reminder to the other readers. If the smoke was noticed quickly and the coach disconnected soon enough, there is a good chance the damage will be minimal, however, the aforementioned tests should still be performed just to be sure.

RV Oven Flashback

My propane RV oven experiences regular flashbacks to the air shutter at the back of the oven. I have tried adjusting the shutters to no avail. Any suggestions on how to fix this?
Waldo, (Palm Springs, CA) 

Waldo, the first thing to check (or have verified) with any propane appliance issue is the delivery line pressure. Too low or too high LP pressure can cause a plethora of operational issues with any and all of the four propane-burning appliances. It’s quite possible the delivery pressure is set too high. Setting the pressure to the correct level necessitates the use of a manometer which any certified RV service tech will have. 

Once the LP pressure has been set to 11.0 inches of water column, the next item to check would be the cleanliness of the main oven burner. Most can be removed with relative ease. Inspect each of the holes in the burner. Look for plugged ports, soiling by cooking greases or possibly an accumulation of oven cleaner or other debris blocking some of the ports.

Next, though in the oven it’s rarely adjustable, check that the oven burner assembly is in alignment with the orifice fitting at the safety valve near the back of the oven. Any misalignment may cause turbulence inside the mixing tube, much akin to a related problem associated with the water heater. The incoming propane draws in air from inside the oven to be mixed prior to it being consumed by the burner. 

Another item to check is the orifice fitting itself. It can be removed, soaked in acetone or a like liquid and then allowed to air dry. Much like the ports in the burner, it is possible cooking oils may have partially blocked the oven orifice. 

Finally, the air shutter should be adjusted so that the main burner flame is steady, with sharp blue points and not lazy or “floating” above the ports. One other cause of your symptom may be a damaged or bent burner assembly. But a close inspection will reveal if that’s the case.

Another Unstable RV Antenna

I have a Winegard crank up TV antenna, and when it's cranked in the up position, it rocks back and forth when the wind blows. Someone told me that there's a tool that can adjust the antenna. Do you know what kind of tool this might be and what I have to do to adjust the antenna?
Larry, (Wolcottville, IN)
 

Larry, Winegard does indeed have a tool that can tighten the integral mechanical gearbox assembly of the antenna. I was not aware of it until a sharp-eyed reader pointed it out to me. It's their part number TT-1000. It amounts to nothing more than a deep-well 15/16" socket.  In the photo here, you can see the nut that needs tightening. Someone apparently used the incorrect size socket as the points of the nut have been rounded off.

But first check to make sure the antenna is mounted correctly to begin with. I've also seen wobbly antennas caused by worn gears. Winegard also offers a gear replacement kit that will probably help the instability problem caused by worn, old-style gears. You can tell if you have the older gears by inspecting the cranking rod from inside the RV. Remove the crank handle and spring by loosening the set-screw and take a look at the shaft that extends down below the ceiling. If the rod is round, it’s the older style; if it’s a hexagon shape, it’s the newer style. But first make sure the antenna is mounted and secured properly. The base should be securely attached to the roof and sealed properly to prevent water intrusion. The antenna mount must be secured to a solid portion of the roof. If it’s sloppy when fully extended, it’s likely to be the worn or loose gears. I'd suggest tightening the gear assembly first using the Winegard tool or a deep socket. If it's still wobbly, it's probably time for new gears.

RV Batteries - 6 or 12 - Volts, That Is

I'm just wondering if I'm better off with two, 6-volt batteries wired in series, rather than using just one 12-volt battery instead. I’ve heard a variety of reasons why and why not. What is your opinion?
David, (North Andover, MA)

 

David, you’ll find this topic both cussed and discussed often! My take? Replacing 12-volt batteries with 6-volt batteries will usually increase the capacity to store amperage. I am a fan of using 6-volt, true deep cycle batteries for the house system when possible. It really boils down to simple math. As an example; two Group 24 (12-volt) batteries connected in parallel yields approximately 170 combined amps of storage (about 85-amps each). Two Trojan 6-volt batteries wired in series yields about 225 amps at 12-volts. The more batteries you add, obviously the more current you’ll be able to store. Four 6-volt batteries wired into a series-parallel configuration, as another example, will provide about 450 amp-hours of use. Even if you had two, larger, Group 27 (12-volt) batteries in parallel, they only total about 210 amps, still less than two 6-volt golf cart batteries connected in series.

When connecting two 6-volt batteries in series, attach the hot lead (from the RV) to the positive post of one battery and the negative lead or ground connection to the negative post of the second battery. A short section of battery cable will connect between the negative post of the first 6-volt battery to the positive post of the other 6-volt battery, completing the 12-volt output configuration (see illustration at left).

Realize that at the basic level, all DC components found in today’s production coaches are powered by 12-volts. If 6-volt batteries are employed, a minimum of two must be connected together in order to provide the 12-volt output needed. If you were to connect two, 12-volt batteries in series, the output voltage would measure 24-volts. Likewise, two 6-volt batteries connected in parallel would yield a nominal 6-volts only. You can see the importance of knowing how your system is wired!

In effect, what exists on the right are two “sets” of 6-volt batteries. Each set contains two 6-volt batteries wired in series and then the two sets are connected together in parallel. If additional storage capacity is desired, another 6-volt set of batteries can be added. In the series/parallel configuration for 6-volt batteries, remember, they must be added in pairs. You cannot have an odd number of 6-volt batteries in the battery bank. And like their 12-volt cousins, for optimum performance, all batteries in any battery bank should be the same type, the same size and the same age. 

RV batteries are a substantial investment, so it makes perfect sense to be able to get the most out of that investment. And my motto has always been; carry as much battery capacity that you have room for and that your wallet can endure.

Thin RV Cap Causes Mounting Dilemma

The license plate and license light bracket are ready to fall off the rear cap of our motorhome. The screws have become loose. How is the best way to reattach these items to a thin wall (about 1/8 inch thick) with foam insulation behind it? There is just nothing for a screw to sink into. Jackson, (Plano, TX) 

The perfect fastener to use in this instance, Jackson, is called a threaded nutsert. Most astute RV repair facilities will have this fastener and its requisite installation tool, especially if they also perform collision repair and other types of RV body work. Nutserts can solve a multitude of mounting and securing issues in aluminum, fiberglass, and other types of thin, RV siding materials. Take a look at this web page for a neat little presentation on how a nutsert is actually installed:

http://www.avdel-global.com/en/products/threaded-inserts/thin-sheet-nutsertr.html

All professional RV service technicians will, (should), have access to a professional nutsert tool. Hope this helps!

RV Gray Water Drains into Black Holding Tank

We have a brand new motorhome produced by a major manufacturer. We like most everything about the rig but one thing about this particular coach really bothers us. Our shower drains into the black tank. Now normally we could dry camp (in our old rig) without needing to empty our black tank for a couple of weeks. Not true here. We have to dump this black tank every single day. We could just give up on showering, I guess. When we contacted the manufacturer about the issue they pretty much told us to take a hike. Are there other motorhomes out there with this same problem and are there any regulations which govern the installation of black tanks at the manufacturing level? If we can't correct this hang-up our $150,000 coach will pretty much be worthless to us, which is just what we've found the manufacturer to be.
Daniel, (Appleton, WI) 

Wow, I’m so sorry to hear of your difficulty with the manufacturer Daniel. It’s unfortunate, but it is permissible for RV manufacturers to allow a liquid fixture to drain into the black water holding tank and still satisfy the requirements of the NFPA 1192, Standard for Recreational Vehicles. This is typically predicated by the design of the floor plan. In my opinion, not the optimum situation.

Most makers, thankfully, do keep the black and gray waste systems separated and relegated to dedicated holding tanks. In those few instances where a gray waste fixture does drain into the black holding tank, typically it will be an infrequently used device like a lavatory sink. Based on your description, it sure sounds like a very poor waste system design.

Now having said that, in some instances, it is possible to re-route the shower drain to the existing gray water holding tank, or better yet, to a newly installed third tank. A competent RV technician will have to inspect the existing waste system to see if that option is feasible. All drains must enter the holding tank at the top of the tank, so gravity filling from the side or bottom of the holding tank is not allowed. A thorough inspection will determine how best to accommodate the modification. I wish I had a more definitive direction for you. But try to find an experienced RV repair facility in your area that can make the alterations. All is not lost yet!

RV Water Heater Pilot Flame-out

My water heater pilot light will not stay lit. I light the pilot and after a short time I am able to light the main burner. However it appears that when the water gets to temperature, the burner shuts off and so does the pilot flame. Any ideas?
George, (Artesia, NM)

 

Here are a few things to check George. First of all, be sure the LP delivery pressure is set correctly to 11.0 inches of water column pressure. My recommendation is to only allow a Certified or Master Certified RV service technician adjust the propane delivery line pressure. Plus I'm guessing it's time to perform a clean & service on the water heater. There are a couple things you can do yourself, however.

First, be sure the control valve is in the "off" position. Then disassemble the pilot burner assembly and be sure it is free from blockages. You can soak the pilot orifice in acetone or denatured alcohol. The pilot assembly itself can be cleaned using a common pipe cleaner after soaking. Allow the parts to air dry. Do not insert any item into the orifice and avoid using compressed air pressure. Inspect the flame spreader portion of the burner assembly and look for bent or damaged components. It must spread the pilot flame evenly in order to heat the thermocouple properly.

Remove and clean the large “J” tube or mixing tube and be sure it is free from blockages of any type, (check out the spider's nest in the photo above). The main burner flame spreader must also be centered in the opening of the “J” tube. Once the mixing tube is removed you can gain access to the main burner orifice. Soak and air dry this orifice also. The main burner orifice must be centered in this mixing tube when you re-assemble so take care to align the parts carefully. 

On the thermocouple itself, clean the tip using 0000 steel wool. Remove all carbon deposits. Re-assemble all components taking care not to over tighten the thermocouple into the gas valve. Just one-quarter turn past finger tight is all that is necessary. Check for gas leaks on any connection you disconnected and re-assembled using a soapy solution or an electronic leak detector. Be sure the soapy solution does not contain ammonia. 

If all checks out, light the pilot and observe the pilot flame as it engulfs the tip of the thermocouple. It should only impinge on the first 1/8-inch or so of the thermocouple. A too big pilot flame could result in pilot outage after the heating cycle. It would also be wise to have a Certified RV service tech measure the thermocouple output; it should produce a minimum 12-14 millivolts DC. A weak thermocouple output could also lead to pilot outage. If all the above tasks prove futile, the cause just may be a weak electromagnet or a faulty internal device called an ECO, both integral components of the gas control assembly in which case it will be necessary to replace the complete gas control valve.

Class C Motorhome Fuel Sending Unit

Where can I find a fuel sending unit for a 1976 Class C, Vogue motorhome?
Chuck, (San Francisco, CA) 

Chuck, if the maker of your Class C Vogue chassis is Dodge, which I suspect it is, I’m guessing the sending unit is a side mounted model with what is called a 78-ohm wrap. It probably has a single draw tube and no vapor return tube. If the problem you are experiencing with the sender is that it reads empty all the time, the problem may or may not actually be the sender itself. Here’s how to tell. 

Use an ohm meter and measure the resistance at the sending unit. It should measure between 8 and 78 ohms if it is working properly. If indeed it does measure a resistance within the above range, check that the wire running from the sender to the fuel gauge is intact. You can do this quickly and easily by turning the ignition key to the “on” position and touching the sender wire at the tank to a good frame ground. If the fuel gauge goes up past the full mark when that wire is grounded, it ensures the sender wire itself is in good condition. If the sender does not measure within the above resistance range, it may simply just need a good cleaning. 

After confirming that the fuel level in the tank is well below the side-mounted sender opening, remove the sender and inspect the wire windings (wraps). Use an electrical contact cleaner to remove any corrosion that may be on the windings. Work the float back and forth; making sure the contact cleaner reaches the full travel. This may be all that is necessary. If it still does not register the fuel level properly, chances are a new or rebuilt sending unit is in your future. If you cannot locate a used one at a local automotive recycling yard, contact Transfer Flow Inc. at 800-442-0056, extension 11. They also repair older senders.

De-tails of De-winterizing an RV

Last autumn, I bought my first RV and had the dealer winterize it after I was done traveling for the year. I want to de-winterize it myself but I'm not sure of what's involved. Can I just flush it out to remove the RV antifreeze? Can I obtain a pamphlet somewhere that covers winterizing/de-winterizing?
Peter, (New Kensington, PA)

Indeed flushing the fresh water system will rid your coach of RV anti-freeze, but there are certainly additional items to check and sequential tasks to perform depending on the extent that dealer performed the winterizing precautions last fall. The steps are too numerous to include in this response, but the November 2009 issue of Family Motor Coaching Magazine published an in-depth look at all the necessary winterizing steps. Additionally, the March 2010 issue holds the companion article for de-winterizing your motorhome. Each article details, step by step, all the procedures necessary for any motorhome. Give FMC Magazine a call and see if you can obtain a reprint of those articles. They'll be good references to rely on each year.

Non-Stop RV Refer Operation

I have been told through second hand information that it is better to let an RV refrigerator run all the time, even when the motorhome is not in use. The technician claimed that when the refrigerator is not running that the fumes from the ammonia will cause corrosion and thus will rot the aluminum to the point that it will leak. He claimed that when left running all the time you will not experience the problem of replacing the unit. Any thoughts on this?
Bob, (Sebring, FL) 

Bob, I can’t say I would put much stock in what that technician told you. There are no ammonia fumes associated with the absorption refrigerator. It’s a completely sealed system. Ammonia is corrosive, true, but 90% of all leaking cooling cores are due to moisture intrusion from outside of the cooling unit pipes, typically inside the foam pack area where it is most difficult for condensation and moisture to evaporate. All the tubing in a cooling unit, by the way, is made from steel, not aluminum. Additionally, during the charging process, a chemical called sodium chromate is induced into the sealed system which coats the inside of the cooling unit tubes, thereby protecting them from any corrosive action of the liquid ammonia.

In my opinion, running the refrigerator when not necessary is basically a waste of energy (120-volts electricity or propane), and puts more wear on the system controls than starting it up as needed. The life of the heating element will likely be shortened if allowed to run continuously on the electric mode. Plus when operating on propane, the burner and flue will need to be cleaned more often. If you have a fairly new RV and refrigerator, battery consumption would also be a concern and the constant operation of the circuit board(s) will also take its toll eventually. I honestly cannot see where there is anything to gain and actually more to lose by letting the refrigerator operate non-stop. But that’s just my opinion. 

Basically it goes back to the definition of an RV as put forth by RVIA; it’s a vehicle made for “temporary” living. A switch to a household-type compressor-driven refrigerator, however, would be a viable option for those RVers with full time hookups and no need for LP operation.

RV Fresh Water Chlorination

The water in our RV had a bad odor; a musty smell, so we added some Clorox to the tank and let it set awhile. Now we cannot get the Clorox taste out. What do you suggest we add to get rid of the Clorox taste?
Stacey, (Sacramento, CA) 

Stacey, foul or stale tasting water can not only ruin a vacation but may even be harmful. But the pungent flavor of Clorox might even be worse; like drinking water from a swimming pool! There is usually sufficient chlorine in most city water supply systems for safe storage in an RV, but if foul tasting water persists, it may be necessary to treat the fresh water system from scratch. Of course, the fresh water container only stores the quality of water put in there, so be sure to taste it prior to filling up. Here’s the approved method of chlorinating the entire fresh water system:

1. Drain and flush the fresh water tank; leave empty. Be sure the water heater is not in the bypass mode.

2. Mix 1/4-cup of liquid household bleach (sodium hypochlorite) solution with one gallon of fresh water. (A clean 1-gallon milk bottle works great for this).

3. Pour directly into the fresh water tank.

4. Pour in one gallon of the chlorine/water solution for every 15 gallons of fresh water tank capacity.

5. Top off the tank with fresh water.

6. Remove or bypass any water purification equipment and/or filtering cartridges.

7. Turn on the water pump and open every faucet in the RV, including exterior faucets or showerheads.

8. Allow the solution to pump through the system to the toilet, through the water heater and to every hot and cold faucet at each sink until a mild odor of chlorine is present at every fixture.

9. At the city water inlet, using the eraser end of a pencil, push in on the check valve spring allowing the solution to pump out through the city water inlet until the chlorine odor is detected in the discharge.

10. Close all the faucets and turn off the water pump.

11. Allow the system to stand for four hours. This will chlorinate and disinfect the system, including the fresh water tank, the water heater, the faucets, the complete piping system and all fittings to a residual level of 50 ppm (parts per million).

12. At four hours, drain and flush the system with fresh water once again.

If 100 ppm residual concentration is required or desired, use 1/2-cup of bleach instead of 1/4-cup with each gallon of the solution and let stand for at least one to two hours. Do not allow the chlorinated solution to sit longer than four hours in the fresh water system to avoid damage to some delicate plumbing components found in some water pumps. This is the approved method to be sure bacteria are effectively eliminated. This process should be performed after any period of nonuse or storage, or whenever stale or distasteful water is experienced. 

Since you’ve already put Clorox in the system, you may have used too much. Just keep flushing it out. Fill the tank, pump it through, drain and refill. If the heavy bleach concentration has permeated the plastic piping severely, you may have to keep pumping fresh water throughout the entire system to be sure all the bleach is eliminated. Eventually the odor of the Clorox will subside. There are aftermarket fresh water additives that can be added to the fresh water tank, but those that I’ve tested consist primarily of chlorine elements and I don’t think you need any more of that. I’ve also heard of adding distilled vinegar to the water system. Add about 1-quart for every 5 gallons of water capacity and pump it through the system as you do with chlorine. Let it stand in the system overnight and, as with chlorine, fully flush the system until you are satisfied with the taste and smell. I’ve not tested this method personally, but if the Clorox taste still remains, it just may be a viable alternative method.