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Monday, March 23, 2015

RV Battery Capacity Question

Hey Doc, will two, T-105, 6-volt batteries be able to crank over and start a generator on a toy hauler? Frank C., (no city/state) 

Indeed and with plenty to spare Frank! But I assume you mean two, charged batteries, right? Two dead batteries of any make would have trouble. But two Trojan T-105s are often used to provide DC power to a whole RV. That’s almost 450-plus amp-hours of storage capacity. If that generator won't crank, there's something else amiss. 

Tuesday, March 17, 2015

Elusive Water Leak

I really enjoyed your training sessions at the Seattle RV Show. I need some suggestions from you. I have a 2007 Navion that I purchased recently. It had a wet spot on the ceiling on the driver's side above the shower. The dealer took it back but couldn't find the leak so they re-caulked all around the skylight and the rear terminator cap. They ran leak tests for three hours and said it didn't leak. They then dried everything out and removed the small stain. This was two weeks ago. Today I felt up there and it is damp again. I will take it back to them, but am worried they won't be so gracious about fixing it. Where would you suggest I have them start to find this leak? Could it be leaking in one of the lights? If they aren't helpful, is there someone you would suggest I take it to. Thank you very much for your help and suggestions. It is appreciated. Donna, (Western WA)

Donna, with so many items attached to the exteriors of RVs water leaks are some of toughest to diagnose and find the entry point(s). There’s truly only one guaranteed method of finding water leaks in an RV. It’s by using the SealTech method. 

Watch this little 3-minute video and you’ll see why.

I’m not sure if your particular dealer has a SealTech machine, but they should! SealTech publishes a list of all companies that have purchased one of their machines. It looks like there is a repair facility in Centralia that has one, but for everyone's benefit, here’s the updated and official SealTech list:

And as I mention in that little video, once water gains entry, it could flow anywhere before it is actually discovered. So I believe SealTech is the best way to go. It’s then up to the expertise of the shop to seal the leak properly. Obviously your dealer wasn't as thorough as they thought they were! 


Wednesday, March 11, 2015

Where To Connect Fresh Water Filter/Purifier

I am new to the RV world and have a question. Should our water filter go between the faucet and the hose, or between the hose and the RV? Or, does it not matter? Thanks, Debi (no city/state)

Welcome to the world of RVs Debi! Believe it or not, this question comes up more often than you'd think. From a water flow perspective, it really doesn't matter. But I subscribe to the thought that it’s best to place an in-line filter or purifier as close to the water source as possible, typically right at the campground spigot. That way you are protecting the hose itself, as well as the fresh water demand system in the RV. Oftentimes it’s near impossible to drain all the water from the hose, and over time, contaminates could gather in a stored hose and then be forced directly into the system the next time you hook up. 

Additionally, it’s wise to connect both ends of the coiled hose together prior to storing it in the rig. And it's always beneficial to carry an adjustable city water pressure regulator as you travel too.

Monday, March 9, 2015

New RVing Blog! - RV Open Road!


Hey RVers! I'm happy to announce a new RVing blog! Take a look at  RV Open Road! 

Published by Lippert Components, Inc., this new interactive blog features, not only never-before-seen RV Doc Q&As, but valuable RVing information from a host of RV experts, bloggers and authors.

I'll be posting regularly and LCI encourages you to comment, quip and suggest topics for future features for not only the blog, but for their new print magazine of the same name, RV Open Road Magazine.

As many of you know, the success of a blog, especially an RVing blog, is directly proportional to the amount of participation by its readers. So feel free to contact RV Open Road at any time regarding an idea, topic or product you'd like to see featured on the blog.

Look for the big green box on the left side of the home page to sign up for an email notice whenever a new blog post appears. Or simply click on the blue box below and do it now! And while you're on the blog, you might as well sign up for the web version of the upcoming RV Open Road Magazine. 

Have a technical question regarding your RV? You can write to me directly at RVdoctor@lci1.com with any questions or issues you may be having with your RV. I'll make every attempt to respond as quickly as possible. And your question just might appear as a post on RV Open Road! 

So I encourage you to take advantage of this new RVing resource today! Subscribe, submit and support, because RVing is more than a hobby, it's a lifestyle! 

Subscribe to RV Open Road Blog

Tuesday, February 17, 2015

RV Furnace Misunderstanding

In a recent RVtravel newsletter a lady states: "I am new to owning and living in an RV so I am not familiar with propane heat. I have read that propane heat also puts out moisture." I believe it may have been prudent to tell her that the propane furnace, being a closed system to the outside air, will have no affect on moisture within the RV.  (No name) 

Actually No name, fresh air is drawn from outside the RV into three of the four propane appliances to mix with the incoming fuel, including the forced air furnace. Yes, it has a sealed combustion chamber, but moisture can still be generated inside the fire box through that fresh air intake. I’ve replaced many RV furnace combustion chambers that have rusted through. All propane flames/burners require a mixture of air and gas in order to support combustion and all will create moisture. The primary air volume is drawn in from outside the coach. That’s why it’s important to have the furnace inspected each camping season. If a rusty hole is created, carbon monoxide (CO) can escape into the living areas of the RV.

Saturday, February 14, 2015

The New LCI Online Parts & Accessories Store


Hey RV Doctor readers! For many months now I’ve had the pleasure of working with the fine folks at Lippert Components. Longtime provider of trailer frames, axles, pin boxes, stabilizers, levelers, slide-out systems, doors, windows and more to the RV industry, Lippert also offers many exciting upgrade accessories to the RV aftermarket! You've heard me say often, "Thank goodness for the aftermarket."

They have created a brand new online store open to every RVer, 24/7, making it easy to find those all-important replacement parts for many of the components on your RV. More importantly, you now can order any of their excellent RV accessories — like Waste Master — and have them ship directly to you. Check out their featured products on the home page or shop for specifics conveniently displayed by department on the left side of the page. I guarantee you’ll find something you simply cannot live without. I’ll even be highlighting some of my favorite products soon, so stay tuned! But do enjoy perusing all the products from one of the largest RV suppliers soon.

Thursday, February 12, 2015

RV Holding Tank Care

I think I've seen more words written about holding tank care and operation than any other single subject. Your discussion in a recent issue of Family Motor Coaching Magazine about cleaning black tanks was interesting and helpful. In the same issue, there was a description of an all-natural, microbial-based holding tank additive that, at least according to the maker, allows the microbes to digest waste such as proteins, oils, grease and paper, all the while preventing odor. If this product does what it says, when I know my motorhome is going to be out of service for a couple of weeks, why wouldn't I empty my black tank and then fill it up with water, dump in the appropriate amount of this product and let those microbes go to work? When I go back on the road, I empty the tank at my first stop and all the microbes and goop go down the drain, leaving me with a shiny, clean tank! There has to be something wrong with this concept but I don't know what it is. Rick C., (Bradenton Beach, FL) 

There is absolutely nothing wrong with your concept Rick. In fact, it is preferential. Bacteria-infused, enzyme-based tank additives can indeed help break down the solids and consume many of the odor-causing molecules at the root level. Keep in mind, however, it's not truly designed to clean the holding tanks. I’m not sure what brand of all-natural additive you saw, but the one I recommend is Pure Power Blue, sold by Valterra. While I’m not in favor of masking holding tank odors in hopes to not be distracted by them, (there are other aftermarket products available that truly eliminate sewer odors in the RV), I am all for letting the enzymes do the dirty work (excuse the pun!). Masking the odor is considered a band-aid where live bacteria actually perform better in the long run. If you’ve been using caustic chemicals or bleach or other bacteria-killing additives, it might be necessary to first “season” the holding tank to create a livable environment that encourages the good bacteria to be effective. So it may take a couple of flushings to be rid of the chemicals. Read the instructions on the container carefully. Most will come in liquid or solid form. Personally, I feel the liquid additive (at least with Pure Power Blue), works fastest. See my review of PPB here. But you’re spot on with your idea. 

By the way, my wife and I grew up in Bradenton and still have relatives there so we visit often. We always go to the Rod & Reel Pier Restaurant on Anna Maria Island for lunch every time we visit. Can't beat their grouper sandwiches!

Friday, February 6, 2015

Smoke Gets in Your Eyes

I'm trying to find out what I have to do in order to fix this power issue. When I last parked my trailer I plugged it into a 50 amp shore power source. Then while trying to raise the power jacks in order to unhook the truck, the switch wouldn't work. It was like there was no power at the switch. So I clicked the battery power switch on in order to use the battery power. It worked fine but after raising the trailer I noticed and smelled smoke. It was like a burning electrical smell. I opened the door for the garage and it was full of smoke. After the smoke cleared I'm pretty sure the smoke was coming from the electric motor that raises and lowers the power jacks. After this I started looking into the problem further and noticed one of the electric breakers that controls the power converter was tripped off and it would not stay reset. Then I unplugged from the 50 amp and with the plugin adapter plugged into 30 amp shore power. That seemed to fix everything and I've been running it that way since (about 3 weeks). I have the trailer for sale and don't want to sell it without fixing this issue. Please point me in the right direction. I don't want to call an RV repair dealer because I've been ripped off by them before. Thanking you in advance... Gary S., (Lisbon, OH)

Gary, with all the accoutrements that come with a coach that large, the 12-volt power demand is huge. Some manufacturers fail to let their customers know about the vital importance of having enough battery power to operate all things 12-volt. Plus that battery disconnect switch must be off in order to have 12-volts distributed throughout the coach. I’m not sure how many batteries are in your bank, but it’s doubtful the full load of those landing jacks lifting that much weight can be adequately provided by the converter/charger alone. There may be something internal to the converter that is not allowing it to fully charge the battery bank, but the symptom suggests a low amount of voltage in the batteries. When connected to 30-amp shore power, is the converter still in operation? With less power available, it’s possible the converter/charger is not being powered by 120-volts AC from the shore line at 30-amps service. If you send me the brand and model of the converter, I can delve deeper into that device.

Another thing some RV makers fail to understand is the negative side of the DC system. Be sure the negative cables are greater than or equal to the size/amperage rating of the positive cables. The high current demand of the landing jacks under load could have overheated the motor by a lack of proper grounding. If possible, fully charge the battery bank independently of the converter/charger and see if the jacks operate normally. If so, we can focus attention to the converter itself.

With 50-amp service and the converter operational, is there a voltage increase, as measured at the battery bank? It’s possible the converter is undersized for the 12-volt demands of the entire coach. Adding the high current demand of those landing jacks possibly overheated the motor causing it to smoke. Typically they are protected by an internal breaker so hopefully no internal damage exists. Have you noticed other 12-volt devices with problems? Dim lighting, slow fan speed on the furnace, low water pressure from the pump, etc.? If other devices exhibit problems, I’d focus on the ground cables and all connections, plus the state of charge of the batteries.

Loose connecting points can also cause overheating and smoke. If the problem is dedicated to only the powered landing jacks, then it could be a problem with the jack motor or possibly the converter. Another question; do you have a power management load center? One that sheds loads if power consumption is exceeded? When operating on 30-amp service, some devices cannot operate unless the management load center can make that decision based on load requirements. Sounds confusing, I know. But until we have some specifics about the individual components, we're just guessing.

Send me the specs on the converter/charger and the landing jacks, and how many and what type of batteries are in the battery bank and I’ll dig further. There’s a logical explanation in there somewhere.

Monday, January 26, 2015

Fluctuating Line Voltages in Motorhome

I have 2013 Endeavor 43RFT. The Power Control System Central Monitor Panel is showing that the L1 and L2 voltages are fluctuating 3-volts every one to five seconds, (e.g. 118v then 121v then 118 then 121 etc.). Per Monaco Help Line, I have tightened all the screws in the distribution panel and in the transfer switch. This occurs whether I am on shore power or generator (but not when inverting). Monaco Help Desk could not offer any other help, how about you? My inverter is a Magnum MS-2812 and the transfer switch is SurgeGuard 41260. Jim L. (Huntsville, TX area)

Jim, this particular transfer switch does not contain any electronic components and is reliable, so we can rule out any problem with that device. And your inverter likely produces a purer sine wave than that off the grid, so that leaves only the coach loads as the possible suspects since you’ve already addressed the connections (be sure you've checked and tightened them all). The next thing to do is to isolate the problem to a specific circuit, then locate the culprit component within that circuit. 

Start by powering up the coach (either by shore power or generator), and turning the branch circuit breakers off completely. Monitor the voltage with all the branch circuits disengaged; the voltage should not be fluctuating at this point (if it is, there's likely a problem with the source voltage itself). Then turn on each breaker one at a time and allow the voltage to stabilize. If the voltage begins fluctuating after turning on a specific breaker...that’s the circuit with the problem.

Next determine which component(s) that circuit is powering. It will likely be something equipped with an overload device that automatically resets such as the heating element in the water heater. Something is causing the current usage to fluctuate, which results in the voltage variances. If you cannot locate the specific component within that circuit, a voltage drop test can be performed to determine exactly where the current leakage is occurring. It could simply be worn insulation on a conductor somewhere if it’s not the actual “load” causing the fluctuation. Unfortunately, it is best left to a professional electrician, one with an understanding of RV electrical systems, to dig beyond this point.

You might want to refer to the coach wiring schematic to determine which components are on each circuit as a guide and have each component tested independently. Even though it may take a Certified RV service technician, the current leakage or fluctuation cause has to be there somewhere! It's pretty much a divide and conquer troubleshooting process.


Friday, January 9, 2015

Keep RV Tires on a Firm Foundation

Love your articles and I have learned so much from you. I have a 2013 Itasca. Being relatively new it does have hydraulic stabilizers which do level it, but right now it is parked in my driveway which has an incline to the road. I want to be able to use if when family comes to visit, but I am trying to figure out how to get it level. The front is probably sitting 10” to 12“ lower than the back. I was told, or read in the manual for the stabilizers, that you should never lift the RV up so high that the tires leave the ground. So I don’t think I can use them to level it. I saw your article about making ramps out of treated 2” lumber and wondered if you thought that would work for me? I would probably have to use six,  2x10 pieces, each a little longer than the first. Also, is it better to raise the front end or the rear? I assume the front since there is only one set of tires. Thanks so much for your help. (Carol B.)

 Carol, indeed those tapered leveling blocks are your best bet. As well as raising the front axle only. Never allow the tires to leave the ground, especially the rear tires. The emergency brake must be engaged and the transmission in Park, both of which affect the drive axle, so keep those rear tires on the ground.


Send me a picture once you build the blocks. Above is a shot of another reader’s set-up. Notice the “stop” block on the very top. Don’t risk running off the top block and damaging sidewall or frame components.

Friday, December 19, 2014

Product Spotlight: H2Out Dehumidifiers

Dear RV Doctor, I am new to owning and living in an RV so I am not familiar with propane heat. I have read that propane heat also puts out moisture. What is the best way, easiest and most economical, to handle moisture and condensation in an RV? Thanks! Jacki

Hey Doc, I have a 25-foot RV with a new 13,500 btu air conditioning unit. The problem is at night time the humidity level is high, over 80%, with the temperature around 70-degrees. What should I do? Dustin

Well Jacki and Dustin, it's true any gas-fired burner emits moisture (propane, natural gas, etc.), as well as rooftop air conditioners. And indeed moisture can be problematic in and around any RV. There are a multitude of desiccants commercially available that can help reduce moisture accumulation and I've experimented with many over the years since pervasive moisture/condensation have been a never-ending battle for RVers in most climates. 

I recently completed a test of a renewable dehumidifier that uses no electricity and does not require messing dumping of the water it collected. It's called H2Out. The nice thing is that it is available in varying sizes/capacities making it the perfect companion for RV travelers. And since there is no water collecting there's no fear of spillage as you travel up and down hills in the RV. And the best part; it works!

The H2Out is comprised of silica gel modules as opposed to solid silica clay particles. Silica gel can absorb up to one third its own weight. And each H2Out dehumidifier contains thousands of gel beads encased in a stainless steel canister that is easily stored, used and renewed. Renewed properly periodically, each canister will likely last the life of your RV.

The gel beads are normally blue in color and turn to pink as they absorb the moisture in the air. Depending on the size of the canister, they should easily last 30-60 days before needing renewing. At least that's what their literature stated. I ran my tests for a full 90 days just to see what would happen. 

For my review of the SD309, I first ran a three-month test of an unheated space, unprotected by a dehumidifier. I measured the humidity and temperature extremes during this benchmark test. I then placed the H2Out in the same space for another 90 days and measured both extremes again.

Here are the overall results:

Without Dehumidification                                     With the H2Out in Place
Temperature Extremes: 68 - 79-degrees                Temperature Extremes: 54 - 81-degrees
Humidity Extremes: 31 - 43%                                  Humidity Extremes: 24 - 69%

The test was performed in Seattle, WA where the moisture content can vary drastically over the course of the year. Clearly the H2Out obtained the lowest humidity measurement. The benchmark test was performed from late spring to early summer (May - July). The time period for the H2Out test ran from July to September.

The beads began turning slightly pink within a week, which is normal since the moisture is absorbed from the outside to the inside. After 90 days, it was clear it was time to recharge the canister. I'm convinced I would have gotten better results had I recharged the H2Out at the recommended 60-day mark. 

The renewing process is quite simple if you have an electric oven, (uh...don't place the stainless steel canister in a microwave!). It was a little more detailed with my gas cooktop. Do read the recharging instructions carefully! My test canister is now back in my controlled space to see how it performs during a 60-day run of a NW winter.

I am convinced the H2Out is quite worthy of its stout price since it will literally last for years with proper renewing. At the suggestion of Marilyn at Ken Murphy Associates, I plan to place an SD106 in my refrigerator. Though it's probably harder to quantify since I'll not record measurements, I'm informed it works wonderfully inside the food compartment of any absorption refrigerator.

I'd recommend readers visit the H2Out website and read through the informative pages. Though more costly than other, higher maintenance dehumidifiers, I feel serious RVers need to at least check it out.

Wednesday, November 26, 2014

Propane Pigtails Needed

I'm replacing a pair of 12" propane pigtails as shown in one of your earlier posts. The only problem is I don't want to buy garbage. The last set lasted just under a year. What brands should I consider? Patrick, (Austin, TX)

 Patrick, I'm a big fan of Marshall propane products made right here in the USA. I'd avoid any and all imported propane components. It's my opinion that they are less than stellar in quality and quality control. According to the Marshall catalog, those pigtails come in the following lengths: 12, 15, 18, 20, 24, 30, 36, 48 and 60 inches. Here's an 18-inch version I found on Amazon. 

But you'll want the green QCC ACME nut on one end and I would guess either a 1/4-inch inverted flare or a threaded male pipe connector on the other end. However, they are available with a myriad of fittings on the regulator end should yours be anything different. You can check out the website and download their catalog right here. Any local RV service center or accessory store should be able to order a set for you if you'd rather buy in person.

Keep in mind, neither the green ACME hand nut nor the inverted flare fitting requires a sealant, but if the regulator end you need is MPT (male pipe thread), you'll definitely need a sealant applicable to flammable gases. Many RVers mistakenly use white Teflon tape as the sealant. The white tape is not compatible with propane gas. The yellow tape, however, is. 

To see what goes on inside those pigtails, check out this earlier post.

Tuesday, November 18, 2014

Winterizing and Electrical Questions

I recently purchased a 2007 R-Vision Trailite RV. I live in Iowa and am trying to winterize it but when I put the RV antifreeze in, I can’t get it to circulate throughout the system. Am I doing something wrong or do you think I have a bad pump? The owner’s manual has very sparse information. I also have a couple of plug-ins that don’t have any juice. Do you happen to know where I can get an electrical diagram for this camper? Thanks! Bill A. 

Bill, the easiest way to induce the RV anti-freeze into the system is to pour a couple gallons directly into the fresh water tank and allow the 12-volt pump to pump it through the system. Are you saying your water pump won’t operate at all? You can also empty the tank, disconnect the hose leading to the water pump inlet and insert that hose into a bottle of RV anti-freeze, but that still requires the RV’s water pump. There are also kits available that attach to the kitchen faucet where you can “back fill” the system using a manual hand pump. Some RVs are equipped with a "tee" fitting and valve located between the tank and pump that permits a short section of hose to be inserted directly into the bottle of RV anti-freeze. These types of kits can easily be added after the fact. Some even come equipped with a separate, permanent tank for the anti-freeze. Let me know if you are experiencing a water pump issue. But if it pumps water, it will pump anti-freeze.

I’m assuming the “plug-ins” you refer to are 120-volt AC receptacles. If all the circuit breakers are turned on and you do have power at other receptacles, check the GFCI mounted in the lavatory or galley. It’s likely tripped and is protecting more than just that receptacle. Simply push the reset button and then check those other receptacles. GFCI’s are usually configured to protect the bathroom and/or galley circuit PLUS all other receptacles installed downstream of that one.

Personally I do not have source for an electrical diagram (if one even exists). R-Vision does, however, have an active club online at this website. But alas, you must be a member to search the forum. I'd suggest you join that organization and see if any of the members have access to the diagram you are looking for. Individual brand RV clubs are great sources of information, from owner to owner. Almost certainly you'll gain additional help from that group.

Wednesday, November 12, 2014

Swap RV Water Heator for Electric-Only

I will have to change my water heater on my RV because it is leaking. My question is: Can I replace it with an electric water heater only. I am not doing dry camping anymore so I was wondering if it was alright to have only an electric heater tank instead. Awaiting your reply and I thank you. Reinelde L.

 Reindelde, are you 100% sure your current water heater does not have an AC electrical heating element in it already? Many RV water heaters are equipped with an electric option along with the propane burner. I could tell from the model number or a photo of the data plate. If yours does, it may be less expensive to simply replace the inner tank that is leaking. If yours does not, the only drawback to installing an electric only heater, besides the labor costs, is when considering resale or trade-in value. Most RVers would certainly want an RV water heater so unless you plan on keeping that RV forever, I’d stick with an RV heater with an electric element.

But can you install an electric water heater? Sure, as long as the wiring and heater are installed properly by a certified RV technician. There are codes and standards that must be maintained for both the fresh water plumbing and the electrical circuit concerning those modifications. But if an aftermarket electric water heater fits in the same space, go for it!

Thursday, November 6, 2014

Sagging RV Roof Relief

Doc, I have read your solution on repairing sagging roofs with plywood. You mention in your answer that you can put this spacer between the metal roof and the roof rafters. Can you do this same procedure for rubber roofed RVs? Thanks, Larry B.

Larry, that earlier solution you read pertained only to hollow roof systems with aluminum sheathing simply installed over roof rafters; what we call “stick” construction. Though there may still be a few out there, the vast majority of RVs today have a vacuum-bonded, solid roofing structure. Basically it’s a one-piece roof consisting of plywood decking on top, some type of insulation installed between the support rafters (wood, aluminum or steel), with a panel type of ceiling finish. The whole structure is built on a flat, vacuum table, glued together and set on top of the walls. The synthetic membrane (sometimes fiberglass or aluminum) is then installed once the roof is secured to the side walls.

So the sagging roof solution in that earlier Q&A does not apply to one-piece, synthetic roofs like EPDM, TPO or fiberglass, unfortunately. The solution for a sold roof that sags is to first determine and rectify why it sags, then remove the rubber membrane and either replace the top decking with thicker plywood (preferred), or simply install another layer of plywood over the existing plywood decking. Of course, this assumes all the rafters and support members are not damaged and remain intact. But rather than installing rubber membrane again, I recommend a newer type of roofing system called RV Armor. Take a look at this web page and watch this video about the RV Armor system. It is actually preferred to install the RV Armor system on plain wood decking rather than over the final finish material when possible, so you have a golden opportunity now if you replace the decking. As I often state, serious RVers should definitely investigate its benefits!

Thursday, October 16, 2014

RV Generator Over-Voltage

Doc, I recently went to exercise my RV generator and I was surprised when at about 5 minutes after turning on the generator I saw the voltage meter running at about 160-volts and it suddenly sparked but kept functioning. We turned on the AC and all the lights, although one blew. It looked to be to bright. Even with everything on the RV on it brought the voltage down to about 140-volts. I am assuming this is not a good thing and possibly dangerous. I thought it was supposed to be around 120. Can you tell me how this happens? It was running fine before I took the RV to have it serviced. A belt was squeaking and they repaired that but now I have a problem with the generator. Also you advise not running any equipment while the generator is putting out this much electricity. Unfortunately I have run my AC's while it was doing this. They seemed to run fine. But since I have done it is there some maintenance step I should take at this point for them? Again thanks for your assistance. Dale V., (Nashville, TN)

Dale, there are a few reasons why any generator may get out of adjustment depending on the condition of the unit, the number of hours, etc. It’s always been a good idea to have the generator tested annually using a load bank. The load bank device can monitor the voltage (carburetor) and the frequency (governor) as incremental loads (amperage) are placed on the generator. It’s possible someone tried to adjust the generator engine by ear or by sensing how smooth it runs, etc. I mention this fact in my articles, videos and in my seminars, but ANY mechanical adjustment done to the generator has a predictable electrical result. That’s exactly why a tech cannot tune a generator by ear.

Normal wear, carbon buildup, poor quality fuel, bumps and vibrations, etc., can all affect these finer adjustments. Combined, they create the reasons why it’s important to have the RV generator attached to a load bank... I say every year, but no less than once every two years.

If your air conditioners survived 140-volts AC for a long duration, you were quite lucky! Roof A/Cs are quite susceptible to very high and very low voltages. There’s nothing to check on the A/C units if they operate properly on shore power. If they operate correctly on shore power, no damage was done. Also, by connecting to shore power you can check all other AC system components to see if any were damaged by the high voltage. But be sure to have the voltage and frequency checked on the generator by a specialist equipped with the proper diagnostic testers before relying on it. The safe spectrum for AC electricity, (by any source), is 120-volts AC, +/- 5%. 

Thursday, September 4, 2014

Loud Thumping Noise From RV Propane Regulator

Hey Gary, our goal in buying a new travel trailer is/was to enjoy the outdoors, but we are experiencing a relative thumping sound anytime an appliance is utilized which runs solely off propane. Watch this little video:


You will see me adjust the tank selection valve (slightly) to make it go away, only to have it come back on. Our bed is located just behind the tanks/regulator which makes sleeping a thing of the past. This trip out, I shut off the propane valves all together at the tanks, but we would still get the noise, one pop at a time in fifteen minute increments. That said, if you could point me in the right direction I will relay it to the tech if I can’t fix it myself. During my first conversation with the tech, he advised spraying WD-40 into the regulator which doesn't make sense as its completely sealed and any liquid sprayed into the coupling would then be sent to my appliances via the propane hose. I’m sure there is a fix, I just got to find it. We have taken it out only twice and the tanks (propane) were full upon delivery of the trailer. Also this noise comes on regardless which is selected as the primary, both tanks are open or one. We thank you! Shawn & Angie L., (Walla Walla, WA)

Shawn and Angie, that is one annoying noise! Propane regulators can and do create an audible whistling or humming noise while operating. Some humming, caused by the vibration of the diaphragm inside the regulator, is normal, but not a banging or clanging noise such that you are experiencing. But the recommendation regarding WD-40 is 100% incorrect! Never spray anything into the gas regulator! Typically the noise you are hearing is not created by the regulator or the changeover valve, but rather from the pigtails that run from each cylinder to the changeover mechanism atop the secondary pressure regulator. I’m personally appalled at the quality of the propane equipment used today. Most of the components are cheaply produced, usually acquired off-shore and quite deficient when compared to the quality of the yesteryear’s products.

Each propane pigtail contains a redundant safety mechanism called an excess-flow check valve inside the ACME nut that attaches to the manual service valve at each cylinder. This excess-flow check valve consists of a spring, an orifice, a brass seat and a ball bearing along with other safety components forming, effectively, a flow-limiting device at each DOT cylinder. Here’s what it looks like inside the ACME nut:

The purpose of the flow-limiting portion of the ACME connector nut is to restrict the flow of propane gas should an excessive leak exist anywhere in the propane system; it’s a safety device. Just about every time the DOT cylinder service valve is opened, this small ball bearing in the nut assembly is moved towards the piping system and into a brass seat, restricting the flow of gas. It does not, however, fully shut off the entire gas flow; the ball bearing only restricts it. By design, a small amount of gas is allowed to bypass the ball and continues to flow into the changeover valve, into the second stage regulator and then into the rest of the distribution piping system. As long as all the appliances are turned off and there are no propane leaks anywhere in the system, this small amount of bypass flow quickly builds up enough backpressure that it eventually equals the incoming bypass flow pressure coming through the device. When that happens, the small spring pushes the ball bearing back and off the seat and permits unrestricted flow of gas into the system. This whole process takes about five seconds and is designed to work in this fashion. What you are hearing is the back and forth movement of the ball bearing slamming into the brass seat inside the ACME nut of a cheaply constructed, high pressure pigtail hose. Replace the pigtails with a quality replacement hose. Avoid those cheap (by construction standards), imported hoses that most RV accessory stores stock these days.

There’s an outside chance the second stage regulator is faulty too, but I’m guessing your thumping noise will go away with a pair of quality pigtails installed. To be sure the propane regulator is working properly, have a Certified or Master Certified RV service technician (not that other guy!), run a propane regulator test, including a flow test, lock-up test and timed pressure drop leak test. Also be sure the DOT cylinders are never overfilled. But I'd wager that 90% of the time that banging noise is caused by vastly deficient pigtails.

Monday, August 25, 2014

An RV Roof Guaranteed Forever!

Hey Doc, I read an article some time back that talked about a new liquid re-roofing product  coming onto the market. One advantage of a liquid, is that it may get into all the "nooks & crannies." Any info you can share on this? What is your preference for complete roof protection or re-roofing? I have been reading your articles for many years; they are very informative AND helpful! Thanks! Dr. Bill G. 

Dr. Bill, for 40-plus years I’ve investigated many roofing types, coatings, cleaners, preservatives, sealants and other aftermarket products covering the gamut for both RVs and mobile homes. I’ve tested and evaluated many of these products over the years hoping to find that “silver bullet” product that solves many of today’s RV roofing issues. With the roof of the RV constantly being bombarded by airborne contaminates, the never-ending extremes of the weather, ozone, UV attacks from the sun, etc., it’s been an interesting search indeed. That, coupled with the fact that the RV roof is under constant tension and release via the racking and twisting of the structure as the coach moves down the road, it’s no wonder RV roofing leaks develop so easily. It is suggested by many experts that the Number One cause of RV damage is water intrusion and the RV roof is the first line of defense against that. It’s likely the most vital component on any RV. I do recommend Eternabond tape for repairs, component installations and seam protection, but if you're considering the complete roof as a whole, read on.

Last year I became aware of a service and process called RV Roof Armor. It’s a two-day installation process whereby the complete RV roof is sealed and protected against leaks forever! It comes with a lifetime warranty that stays with the coach. I’ve personally witnessed a complete installation and I’m now convinced this is the only way for serious RVers to go. Their literature states you’ll never have to go up on the roof again and I firmly believe that. The roof becomes totally locked in from gutter to gutter. And the best thing is that they come to you! No matter where you live (at least in the US), they’ll send their trained expert installer to prepare the coach and apply the surface material; it takes two days per coach. I do have to comment that you’ll not find the attention to detail for preserving a leak-proof roof more so than from their trained staff. I was actually blown away by the completeness of the process. Not bound by time constraints as you’d find in a typical RV service shop, these guys do it right the first time since its on their dime if they have to go back a second time. How many service companies offer a full lifetime warranty on their parts and labor? For a roofing product especially! I can’t remember ever seeing that before!

Check them out here.

I’d encourage you to bore down deep in their website. Convince yourself this type of service is for you. But I know I’ve found my “silver bullet" when it comes to full roof protection.

Monday, August 4, 2014

No Auto-Mode on RV Refrigerator

I recently purchased a 2006 Coachman Class A motorhome with a Dometic refrigerator that has an "Auto Mode" switch to start up electrically using 120-volts. It also has a "Gas Mode" switch to start up using propane. After several successful trips using both options, a problem has developed where I can only use the "Gas Mode" switch to start the fridge. It will not start using the "Auto Mode." The light inside will come on so it is getting power but it will not get cold even after 24 hours. Can you advise what is causing this problem? Patrick H., (Hockessin, DE)

Patrick, you say you can run the refrigerator on “Gas Mode,” but when you switch it to “Auto Mode” does the indicator lamp illuminate? You may have a blown fuse on the lower circuit board. It’s relatively easy to check if you have a volt, ohm multimeter. It’s possible you may have a problem with any number of the components or wiring within the AC circuitry, but the most common cause is a blown AC fuse on the lower circuit board. But when it’s running on “Auto Mode,” that indicator lamp should also be lit.  

Here’s what you can do; Unplug the refrigerator from its receptacle at the rear of the refrigerator, through the lower exterior vent. Gain access to the lower circuit board and carefully remove the cover. Once removed, plug the refrigerator back in, turn it on “Auto Mode” and measure for AC voltage at terminals J5 and J6 on the board itself. If the unit is already cold, you may have to turn the thermostat to a lower temperature setting or wait until it warms a bit. You should also read voltage on terminals J7 and J8 as they lead directly to the AC heating element. If you don’t have voltage at these terminals, check for continuity of the 5-amp AC fuse and the 3-amp DC fuse on the board. Chances are the 3-amp DC fuse is good since the DC lamp works inside the refrigerator, but I’m guessing the 5-amp AC fuse is blown. Worst case scenario is the board itself is faulty.

If indeed you have voltage at terminals J7 and J8, then it’s possible you have a burned out heating element. If that is the case, I’d recommend a pro service tech perform the replacement.

Monday, July 28, 2014

Winterize Using A "Schrader Valve?"

I have been hearing about dry winterizing a motorhome using a "Schrader valve" and blowing the water out using an air compressor set on 20-PSI, plus putting some of the pink stuff in the kitchen sink, bath sink and shower drains only. Is this a good idea? If so, how do I find the Schrader valve and where do I install one? Bobbie V., (Florissant, MO)

Bobbie, the device you are seeking that incorporates a Schrader valve is called a blowout plug. It has the air inlet valve (Schrader valve), on one end and a male hose fitting on the other end. Mine is made out of milled aluminum, but I've seen brass blowout plugs as well as inexpensive plastic blowout plugs. I do recommend the metallic type. 

The blowout plug attaches directly to the city water inlet hose connection, but only temporarily; it isn’t a permanent installation. Clean compressed air is then forced into the system to expel the water through the faucets and low point drain locations. It’s the quickest way to rid the fresh water system of water. Professional shops use them all the time while performing winterizing procedures or when any time an RV is going to be stored for any length of time. 

As you drain the fresh water tank and water heater, attach the blowout plug to the city water inlet. Open all faucets plus the hot and cold low level drain valves and then inject clean air. You can certainly apply more than 20-PSI since the entire piping system is pressure-tested at 80-PSI at the factory. And since all the faucets and valves will be open, it will be safe and quicker to use 80-PSI. Be sure it is clean air! Like I tell my seminar attendees, this is your fresh water system! Avoid using gas/filling station air or any air from a compressor equipped with a tank. The chance of contamination is greater if the compressor has a storage tank. 

In addition, pour a 1/4-cup of RV anti-freeze down each drain to fill the P-traps and you should be set for winter or any period of non-use. You can purchase a blowout plug at any RV dealer or service center’s parts and accessories department and many websites on-line.


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